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      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_FirstMortgage4Member_lbl" xml:lang="en-US">First Mortgage Bonds - Series AA [Member]</link:label>
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      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_FirstMortgage5Member_lbl" xml:lang="en-US">First Mortgage5 [Member]</link:label>
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      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_FirstMortgage6Member_lbl" xml:lang="en-US">First Mortgage6 [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_FirstMortgage8Member" xlink:label="msex_FirstMortgage8Member" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage8Member" xlink:to="msex_FirstMortgage8Member_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_FirstMortgage8Member_lbl" xml:lang="en-US">First Mortgage8 [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_FirstMortgage9Member" xlink:label="msex_FirstMortgage9Member" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage9Member" xlink:to="msex_FirstMortgage9Member_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_FirstMortgage9Member_lbl" xml:lang="en-US">First Mortgage9 [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_FirstMortgage10Member" xlink:label="msex_FirstMortgage10Member" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage10Member" xlink:to="msex_FirstMortgage10Member_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_FirstMortgage10Member_lbl" xml:lang="en-US">First Mortgage10 [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_FirstMortgage11Member" xlink:label="msex_FirstMortgage11Member" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage11Member" xlink:to="msex_FirstMortgage11Member_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_FirstMortgage11Member_lbl" xml:lang="en-US">First Mortgage11 [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_FirstMortgage12Member" xlink:label="msex_FirstMortgage12Member" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage12Member" xlink:to="msex_FirstMortgage12Member_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_FirstMortgage12Member_lbl" xml:lang="en-US">First Mortgage12 [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_FirstMortgage13Member" xlink:label="msex_FirstMortgage13Member" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage13Member" xlink:to="msex_FirstMortgage13Member_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_FirstMortgage13Member_lbl" xml:lang="en-US">First Mortgage13 [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_FirstMortgage14Member" xlink:label="msex_FirstMortgage14Member" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage14Member" xlink:to="msex_FirstMortgage14Member_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_FirstMortgage14Member_lbl" xml:lang="en-US">First Mortgage14 [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_FirstMortgage15Member" xlink:label="msex_FirstMortgage15Member" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage15Member" xlink:to="msex_FirstMortgage15Member_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_FirstMortgage15Member_lbl" xml:lang="en-US">First Mortgage15 [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_FirstMortgage16Member" xlink:label="msex_FirstMortgage16Member" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage16Member" xlink:to="msex_FirstMortgage16Member_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_FirstMortgage16Member_lbl" xml:lang="en-US">First Mortgage16 [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_FirstMortgage17Member" xlink:label="msex_FirstMortgage17Member" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage17Member" xlink:to="msex_FirstMortgage17Member_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_FirstMortgage17Member_lbl" xml:lang="en-US">First Mortgage17 [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_FirstMortgage18Member" xlink:label="msex_FirstMortgage18Member" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage18Member" xlink:to="msex_FirstMortgage18Member_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_FirstMortgage18Member_lbl" xml:lang="en-US">First Mortgage18 [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_FirstMortgage19Member" xlink:label="msex_FirstMortgage19Member" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage19Member" xlink:to="msex_FirstMortgage19Member_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_FirstMortgage19Member_lbl" xml:lang="en-US">First Mortgage19 [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_FirstMortgage20Member" xlink:label="msex_FirstMortgage20Member" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage20Member" xlink:to="msex_FirstMortgage20Member_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_FirstMortgage20Member_lbl" xml:lang="en-US">First Mortgage20 [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_FirstMortgage21Member" xlink:label="msex_FirstMortgage21Member" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage21Member" xlink:to="msex_FirstMortgage21Member_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_FirstMortgage21Member_lbl" xml:lang="en-US">First Mortgage21 [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_FirstMortgage22Member" xlink:label="msex_FirstMortgage22Member" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage22Member" xlink:to="msex_FirstMortgage22Member_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_FirstMortgage22Member_lbl" xml:lang="en-US">First Mortgage22 [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_FirstMortgage23Member" xlink:label="msex_FirstMortgage23Member" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage23Member" xlink:to="msex_FirstMortgage23Member_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_FirstMortgage23Member_lbl" xml:lang="en-US">First Mortgage Bonds - Series TT [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_FirstMortgage24Member" xlink:label="msex_FirstMortgage24Member" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage24Member" xlink:to="msex_FirstMortgage24Member_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_FirstMortgage24Member_lbl" xml:lang="en-US">First Mortgage Bonds - Series UU [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_SecuredDebt7Member" xlink:label="msex_SecuredDebt7Member" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_SecuredDebt7Member" xlink:to="msex_SecuredDebt7Member_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_SecuredDebt7Member_lbl" xml:lang="en-US">4.45%, Amortizing Secured Note, due April 20, 2040 [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_FirstMortgage25Member" xlink:label="msex_FirstMortgage25Member" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage25Member" xlink:to="msex_FirstMortgage25Member_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_FirstMortgage25Member_lbl" xml:lang="en-US">First Mortgage Bonds - Series VV [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_FirstMortgage26Member" xlink:label="msex_FirstMortgage26Member" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage26Member" xlink:to="msex_FirstMortgage26Member_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_FirstMortgage26Member_lbl" xml:lang="en-US">First Mortgage Bonds - Series WW [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementEquityComponentsAxis" xlink:label="us-gaap_StatementEquityComponentsAxis" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StatementEquityComponentsAxis" xlink:to="us-gaap_StatementEquityComponentsAxis_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StatementEquityComponentsAxis_lbl" xml:lang="en-US">Equity Components [Axis]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RetainedEarningsMember" xlink:label="us-gaap_RetainedEarningsMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RetainedEarningsMember" xlink:to="us-gaap_RetainedEarningsMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RetainedEarningsMember_lbl" xml:lang="en-US">Retained Earnings [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CommonStockMember" xlink:label="us-gaap_CommonStockMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CommonStockMember" xlink:to="us-gaap_CommonStockMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CommonStockMember_lbl" xml:lang="en-US">Common Stock [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PublicUtilityAxis" xlink:label="us-gaap_PublicUtilityAxis" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PublicUtilityAxis" xlink:to="us-gaap_PublicUtilityAxis_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PublicUtilityAxis_lbl" xml:lang="en-US">Public Utility [Axis]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_SourceOfSupplyMember" xlink:label="msex_SourceOfSupplyMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_SourceOfSupplyMember" xlink:to="msex_SourceOfSupplyMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_SourceOfSupplyMember_lbl" xml:lang="en-US">Source of Supply [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RangeAxis" xlink:label="us-gaap_RangeAxis" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RangeAxis" xlink:to="us-gaap_RangeAxis_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RangeAxis_lbl" xml:lang="en-US">Range [Axis]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MinimumMember" xlink:label="us-gaap_MinimumMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_MinimumMember" xlink:to="us-gaap_MinimumMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_MinimumMember_lbl" xml:lang="en-US">Minimum [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MaximumMember" xlink:label="us-gaap_MaximumMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_MaximumMember" xlink:to="us-gaap_MaximumMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_MaximumMember_lbl" xml:lang="en-US">Maximum [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_PumpingMember" xlink:label="msex_PumpingMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PumpingMember" xlink:to="msex_PumpingMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_PumpingMember_lbl" xml:lang="en-US">Pumping [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_TDMainsMember" xlink:label="msex_TDMainsMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_TDMainsMember" xlink:to="msex_TDMainsMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_TDMainsMember_lbl" xml:lang="en-US">T&amp;D Mains [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_WaterTreatmentMember" xlink:label="msex_WaterTreatmentMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_WaterTreatmentMember" xlink:to="msex_WaterTreatmentMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_WaterTreatmentMember_lbl" xml:lang="en-US">Water Treatment [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_TDServicesMember" xlink:label="msex_TDServicesMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_TDServicesMember" xlink:to="msex_TDServicesMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_TDServicesMember_lbl" xml:lang="en-US">T&amp;D Services [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_GeneralPlantMember" xlink:label="msex_GeneralPlantMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_GeneralPlantMember" xlink:to="msex_GeneralPlantMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_GeneralPlantMember_lbl" xml:lang="en-US">General Plant [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_TDOtherMember" xlink:label="msex_TDOtherMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_TDOtherMember" xlink:to="msex_TDOtherMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_TDOtherMember_lbl" xml:lang="en-US">T&amp;D Other [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_LegalEntityAxis" xlink:label="dei_LegalEntityAxis" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_LegalEntityAxis" xlink:to="dei_LegalEntityAxis_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_LegalEntityAxis_lbl" xml:lang="en-US">Legal Entity [Axis]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_MiddlesexWaterCompanyMember" xlink:label="msex_MiddlesexWaterCompanyMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_MiddlesexWaterCompanyMember" xlink:to="msex_MiddlesexWaterCompanyMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_MiddlesexWaterCompanyMember_lbl" xml:lang="en-US">Middlesex [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_TidewaterUtilitiesIncMember" xlink:label="msex_TidewaterUtilitiesIncMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_TidewaterUtilitiesIncMember" xlink:to="msex_TidewaterUtilitiesIncMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_TidewaterUtilitiesIncMember_lbl" xml:lang="en-US">Tidewater [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_SouthernShoresMember" xlink:label="msex_SouthernShoresMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_SouthernShoresMember" xlink:to="msex_SouthernShoresMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_SouthernShoresMember_lbl" xml:lang="en-US">Southern Shores [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RegulatoryAgencyAxis" xlink:label="us-gaap_RegulatoryAgencyAxis" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RegulatoryAgencyAxis" xlink:to="us-gaap_RegulatoryAgencyAxis_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RegulatoryAgencyAxis_lbl" xml:lang="en-US">Regulatory Agency [Axis]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_DelawarePublicServiceCommissionMember" xlink:label="msex_DelawarePublicServiceCommissionMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DelawarePublicServiceCommissionMember" xlink:to="msex_DelawarePublicServiceCommissionMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_DelawarePublicServiceCommissionMember_lbl" xml:lang="en-US">Delaware Public Service Commission [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_RateCasesStormCostsTankPaintingOtherMember" xlink:label="msex_RateCasesStormCostsTankPaintingOtherMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_RateCasesStormCostsTankPaintingOtherMember" xlink:to="msex_RateCasesStormCostsTankPaintingOtherMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_RateCasesStormCostsTankPaintingOtherMember_lbl" xml:lang="en-US">Rate Cases, Tank Painting, and Other [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueByMeasurementBasisAxis" xlink:label="us-gaap_FairValueByMeasurementBasisAxis" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueByMeasurementBasisAxis" xlink:to="us-gaap_FairValueByMeasurementBasisAxis_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueByMeasurementBasisAxis_lbl" xml:lang="en-US">Measurement Basis [Axis]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CarryingReportedAmountFairValueDisclosureMember" xlink:label="us-gaap_CarryingReportedAmountFairValueDisclosureMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CarryingReportedAmountFairValueDisclosureMember" xlink:to="us-gaap_CarryingReportedAmountFairValueDisclosureMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CarryingReportedAmountFairValueDisclosureMember_lbl" xml:lang="en-US">Carrying amount [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EstimateOfFairValueFairValueDisclosureMember" xlink:label="us-gaap_EstimateOfFairValueFairValueDisclosureMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EstimateOfFairValueFairValueDisclosureMember" xlink:to="us-gaap_EstimateOfFairValueFairValueDisclosureMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_EstimateOfFairValueFairValueDisclosureMember_lbl" xml:lang="en-US">Fair value [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_ConvertiblePreferredStockSeries7Member" xlink:label="msex_ConvertiblePreferredStockSeries7Member" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ConvertiblePreferredStockSeries7Member" xlink:to="msex_ConvertiblePreferredStockSeries7Member_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_ConvertiblePreferredStockSeries7Member_lbl" xml:lang="en-US">Convertible Preferred Stock $7.00 Series [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareRepurchaseProgramAxis" xlink:label="us-gaap_ShareRepurchaseProgramAxis" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareRepurchaseProgramAxis" xlink:to="us-gaap_ShareRepurchaseProgramAxis_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ShareRepurchaseProgramAxis_lbl" xml:lang="en-US">Share Repurchase Program [Axis]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_DividendReinvestmentCommonStockPurchasePlanMember" xlink:label="msex_DividendReinvestmentCommonStockPurchasePlanMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DividendReinvestmentCommonStockPurchasePlanMember" xlink:to="msex_DividendReinvestmentCommonStockPurchasePlanMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_DividendReinvestmentCommonStockPurchasePlanMember_lbl" xml:lang="en-US">Dividend Reinvestment and Common Stock Purchase Plan [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PlanNameAxis" xlink:label="us-gaap_PlanNameAxis" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PlanNameAxis" xlink:to="us-gaap_PlanNameAxis_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PlanNameAxis_lbl" xml:lang="en-US">Plan Name [Axis]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_OutsideDirectorStockCompensationPlanMember" xlink:label="msex_OutsideDirectorStockCompensationPlanMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_OutsideDirectorStockCompensationPlanMember" xlink:to="msex_OutsideDirectorStockCompensationPlanMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_OutsideDirectorStockCompensationPlanMember_lbl" xml:lang="en-US">Outside Director Stock Compensation Plan [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RetirementPlanTypeAxis" xlink:label="us-gaap_RetirementPlanTypeAxis" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RetirementPlanTypeAxis" xlink:to="us-gaap_RetirementPlanTypeAxis_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RetirementPlanTypeAxis_lbl" xml:lang="en-US">Retirement Plan Type [Axis]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PensionPlansDefinedBenefitMember" xlink:label="us-gaap_PensionPlansDefinedBenefitMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PensionPlansDefinedBenefitMember" xlink:to="us-gaap_PensionPlansDefinedBenefitMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PensionPlansDefinedBenefitMember_lbl" xml:lang="en-US">Pension Benefit Plan [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherPensionPlansDefinedBenefitMember" xlink:label="us-gaap_OtherPensionPlansDefinedBenefitMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherPensionPlansDefinedBenefitMember" xlink:to="us-gaap_OtherPensionPlansDefinedBenefitMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OtherPensionPlansDefinedBenefitMember_lbl" xml:lang="en-US">Other Benefits Plan [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementBusinessSegmentsAxis" xlink:label="us-gaap_StatementBusinessSegmentsAxis" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StatementBusinessSegmentsAxis" xlink:to="us-gaap_StatementBusinessSegmentsAxis_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StatementBusinessSegmentsAxis_lbl" xml:lang="en-US">Business Segments [Axis]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RegulatedOperationMember" xlink:label="us-gaap_RegulatedOperationMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RegulatedOperationMember" xlink:to="us-gaap_RegulatedOperationMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RegulatedOperationMember_lbl" xml:lang="en-US">Regulated [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_UnregulatedOperationMember" xlink:label="us-gaap_UnregulatedOperationMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_UnregulatedOperationMember" xlink:to="us-gaap_UnregulatedOperationMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_UnregulatedOperationMember_lbl" xml:lang="en-US">Non - Regulated [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ConsolidationItemsAxis" xlink:label="us-gaap_ConsolidationItemsAxis" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ConsolidationItemsAxis" xlink:to="us-gaap_ConsolidationItemsAxis_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ConsolidationItemsAxis_lbl" xml:lang="en-US">Consolidation Items [Axis]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IntersegmentEliminationMember" xlink:label="us-gaap_IntersegmentEliminationMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IntersegmentEliminationMember" xlink:to="us-gaap_IntersegmentEliminationMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IntersegmentEliminationMember_lbl" xml:lang="en-US">Inter-segment Elimination [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CollateralAxis" xlink:label="us-gaap_CollateralAxis" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CollateralAxis" xlink:to="us-gaap_CollateralAxis_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CollateralAxis_lbl" xml:lang="en-US">Collateral [Axis]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EquitySecuritiesMember" xlink:label="us-gaap_EquitySecuritiesMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EquitySecuritiesMember" xlink:to="us-gaap_EquitySecuritiesMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_EquitySecuritiesMember_lbl" xml:lang="en-US">Equity Securities [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:label="us-gaap_FairValueByFairValueHierarchyLevelAxis" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueByFairValueHierarchyLevelAxis" xlink:to="us-gaap_FairValueByFairValueHierarchyLevelAxis_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueByFairValueHierarchyLevelAxis_lbl" xml:lang="en-US">Fair Value, Hierarchy [Axis]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueInputsLevel1Member" xlink:label="us-gaap_FairValueInputsLevel1Member" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueInputsLevel1Member" xlink:to="us-gaap_FairValueInputsLevel1Member_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueInputsLevel1Member_lbl" xml:lang="en-US">Fair Value, Level 1 [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis" xlink:label="us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis" xlink:to="us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DefinedBenefitPlanByPlanAssetCategoriesAxis_lbl" xml:lang="en-US">Defined Benefit Plan, Asset Categories [Axis]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_PreferredEquitySecuritiesMember" xlink:label="msex_PreferredEquitySecuritiesMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PreferredEquitySecuritiesMember" xlink:to="msex_PreferredEquitySecuritiesMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_PreferredEquitySecuritiesMember_lbl" xml:lang="en-US">Preferred Equity Securities [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueInputsLevel2Member" xlink:label="us-gaap_FairValueInputsLevel2Member" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueInputsLevel2Member" xlink:to="us-gaap_FairValueInputsLevel2Member_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueInputsLevel2Member_lbl" xml:lang="en-US">Fair Value, Level 2 [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueInputsLevel3Member" xlink:label="us-gaap_FairValueInputsLevel3Member" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueInputsLevel3Member" xlink:to="us-gaap_FairValueInputsLevel3Member_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueInputsLevel3Member_lbl" xml:lang="en-US">Fair Value, Level 3 [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AwardTypeAxis" xlink:label="us-gaap_AwardTypeAxis" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AwardTypeAxis" xlink:to="us-gaap_AwardTypeAxis_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AwardTypeAxis_lbl" xml:lang="en-US">Award Type [Axis]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RestrictedStockMember" xlink:label="us-gaap_RestrictedStockMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RestrictedStockMember" xlink:to="us-gaap_RestrictedStockMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RestrictedStockMember_lbl" xml:lang="en-US">2008 Restricted Stock Plan [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PurchaseCommitmentExcludingLongtermCommitmentAxis" xlink:label="us-gaap_PurchaseCommitmentExcludingLongtermCommitmentAxis" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PurchaseCommitmentExcludingLongtermCommitmentAxis" xlink:to="us-gaap_PurchaseCommitmentExcludingLongtermCommitmentAxis_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PurchaseCommitmentExcludingLongtermCommitmentAxis_lbl" xml:lang="en-US">Purchase Commitment, Excluding Long-term Commitment [Axis]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PurchaseCommitmentMember" xlink:label="us-gaap_PurchaseCommitmentMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PurchaseCommitmentMember" xlink:to="us-gaap_PurchaseCommitmentMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PurchaseCommitmentMember_lbl" xml:lang="en-US">NJ Water Supply Authority [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_PurchaseCommitment1Member" xlink:label="msex_PurchaseCommitment1Member" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PurchaseCommitment1Member" xlink:to="msex_PurchaseCommitment1Member_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_PurchaseCommitment1Member_lbl" xml:lang="en-US">Regulated Water Authority [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_PurchaseCommitment2Member" xlink:label="msex_PurchaseCommitment2Member" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PurchaseCommitment2Member" xlink:to="msex_PurchaseCommitment2Member_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_PurchaseCommitment2Member_lbl" xml:lang="en-US">City of Dover [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtSecuritiesMember" xlink:label="us-gaap_DebtSecuritiesMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DebtSecuritiesMember" xlink:to="us-gaap_DebtSecuritiesMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DebtSecuritiesMember_lbl" xml:lang="en-US">Debt Securities [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_ConvertiblePreferredStockSeries8Member" xlink:label="msex_ConvertiblePreferredStockSeries8Member" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ConvertiblePreferredStockSeries8Member" xlink:to="msex_ConvertiblePreferredStockSeries8Member_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_ConvertiblePreferredStockSeries8Member_lbl" xml:lang="en-US">Convertible Preferred Stock $8.00 Series [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongtermDebtTypeAxis" xlink:label="us-gaap_LongtermDebtTypeAxis" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LongtermDebtTypeAxis" xlink:to="us-gaap_LongtermDebtTypeAxis_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LongtermDebtTypeAxis_lbl" xml:lang="en-US">Long-term Debt, Type [Axis]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_NewJerseyEconomicDevelopmentAuthorityMember" xlink:label="msex_NewJerseyEconomicDevelopmentAuthorityMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_NewJerseyEconomicDevelopmentAuthorityMember" xlink:to="msex_NewJerseyEconomicDevelopmentAuthorityMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_NewJerseyEconomicDevelopmentAuthorityMember_lbl" xml:lang="en-US">New Jersey Economic Development Authority [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_NewJerseyInfrastructureBankMember" xlink:label="msex_NewJerseyInfrastructureBankMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_NewJerseyInfrastructureBankMember" xlink:to="msex_NewJerseyInfrastructureBankMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_NewJerseyInfrastructureBankMember_lbl" xml:lang="en-US">New Jersey Infrastructure Bank [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_DelawareStateRevolvingFundMember" xlink:label="msex_DelawareStateRevolvingFundMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DelawareStateRevolvingFundMember" xlink:to="msex_DelawareStateRevolvingFundMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_DelawareStateRevolvingFundMember_lbl" xml:lang="en-US">Delaware State Revolving Fund [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_SecuredDebt1Member" xlink:to="msex_SecuredDebt1Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_SecuredDebt1Member_2_lbl" xml:lang="en-US">Amortizing Secured Note, due May 19, 2028 [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_SecuredDebt2Member" xlink:to="msex_SecuredDebt2Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_SecuredDebt2Member_2_lbl" xml:lang="en-US">Amortizing Secured Note, due August 25, 2030 [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_SecuredDebt3Member" xlink:to="msex_SecuredDebt3Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_SecuredDebt3Member_2_lbl" xml:lang="en-US">Amortizing Secured Note, due September 19, 2031 [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_StateRevolvingTrustNoteMember" xlink:to="msex_StateRevolvingTrustNoteMember_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_StateRevolvingTrustNoteMember_2_lbl" xml:lang="en-US">State Revolving Trust Note, due December 31, 2022 [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_StateRevolvingTrustNote1Member" xlink:to="msex_StateRevolvingTrustNote1Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_StateRevolvingTrustNote1Member_2_lbl" xml:lang="en-US">State Revolving Trust Note, due May 1, 2025 [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_StateRevolvingTrustNote9Member" xlink:to="msex_StateRevolvingTrustNote9Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_StateRevolvingTrustNote9Member_2_lbl" xml:lang="en-US">State Revolving Trust Note, due March 1, 2026 [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_StateRevolvingTrustNote3Member" xlink:to="msex_StateRevolvingTrustNote3Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_StateRevolvingTrustNote3Member_2_lbl" xml:lang="en-US">State Revolving Trust Note, due December 1, 2026 [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_StateRevolvingTrustBondMember" xlink:to="msex_StateRevolvingTrustBondMember_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_StateRevolvingTrustBondMember_2_lbl" xml:lang="en-US">State Revolving Trust Bond 4.00% to 5.00%, due August 1, 2021 [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_StateRevolvingTrustBond1Member" xlink:to="msex_StateRevolvingTrustBond1Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_StateRevolvingTrustBond1Member_2_lbl" xml:lang="en-US">State Revolving Trust Bond 0.00%, due August 1, 2021 [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_StateRevolvingTrustNote4Member" xlink:to="msex_StateRevolvingTrustNote4Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_StateRevolvingTrustNote4Member_2_lbl" xml:lang="en-US">State Revolving Trust Note, due July 1, 2028 [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_StateRevolvingTrustNote5Member" xlink:to="msex_StateRevolvingTrustNote5Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_StateRevolvingTrustNote5Member_2_lbl" xml:lang="en-US">State Revolving Trust Note, due January 1, 2028 [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_StateRevolvingTrustNote6Member" xlink:to="msex_StateRevolvingTrustNote6Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_StateRevolvingTrustNote6Member_2_lbl" xml:lang="en-US">State Revolving Trust Note, due August 1, 2031 [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_SecuredDebt4Member" xlink:to="msex_SecuredDebt4Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_SecuredDebt4Member_2_lbl" xml:lang="en-US">Amortizing Secured Note, due April 20, 2029 [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_SecuredDebt5Member" xlink:to="msex_SecuredDebt5Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_SecuredDebt5Member_2_lbl" xml:lang="en-US">Amortizing Secured Note 7.05%, due January 20, 2030 [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_SecuredDebt6Member" xlink:to="msex_SecuredDebt6Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_SecuredDebt6Member_2_lbl" xml:lang="en-US">Amortizing Secured Note 5.69%, due January 20, 2030 [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_StateRevolvingTrustNote7Member" xlink:to="msex_StateRevolvingTrustNote7Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_StateRevolvingTrustNote7Member_2_lbl" xml:lang="en-US">State Revolving Trust Note, due July 1, 2031 [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_StateRevolvingTrustNote8Member" xlink:to="msex_StateRevolvingTrustNote8Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_StateRevolvingTrustNote8Member_2_lbl" xml:lang="en-US">State Revolving Trust Note, due November 30, 2030 [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage1Member" xlink:to="msex_FirstMortgage1Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_FirstMortgage1Member_2_lbl" xml:lang="en-US">First Mortgage Bonds - Series X [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage3Member" xlink:to="msex_FirstMortgage3Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_FirstMortgage3Member_2_lbl" xml:lang="en-US">First Mortgage Bonds - Series Z [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage5Member" xlink:to="msex_FirstMortgage5Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_FirstMortgage5Member_2_lbl" xml:lang="en-US">First Mortgage Bonds - Series BB [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage6Member" xlink:to="msex_FirstMortgage6Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_FirstMortgage6Member_2_lbl" xml:lang="en-US">First Mortgage Bonds - Series CC [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage8Member" xlink:to="msex_FirstMortgage8Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_FirstMortgage8Member_2_lbl" xml:lang="en-US">First Mortgage Bonds - Series EE [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage9Member" xlink:to="msex_FirstMortgage9Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_FirstMortgage9Member_2_lbl" xml:lang="en-US">First Mortgage Bonds - Series FF [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage10Member" xlink:to="msex_FirstMortgage10Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_FirstMortgage10Member_2_lbl" xml:lang="en-US">First Mortgage Bonds - Series GG [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage11Member" xlink:to="msex_FirstMortgage11Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_FirstMortgage11Member_2_lbl" xml:lang="en-US">First Mortgage Bonds - Series HH [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage12Member" xlink:to="msex_FirstMortgage12Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_FirstMortgage12Member_2_lbl" xml:lang="en-US">First Mortgage Bonds - Series II [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage13Member" xlink:to="msex_FirstMortgage13Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_FirstMortgage13Member_2_lbl" xml:lang="en-US">First Mortgage Bonds - Series JJ [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage14Member" xlink:to="msex_FirstMortgage14Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_FirstMortgage14Member_2_lbl" xml:lang="en-US">First Mortgage Bonds - Series KK [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage15Member" xlink:to="msex_FirstMortgage15Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_FirstMortgage15Member_2_lbl" xml:lang="en-US">First Mortgage Bonds - Series LL [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage16Member" xlink:to="msex_FirstMortgage16Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_FirstMortgage16Member_2_lbl" xml:lang="en-US">First Mortgage Bonds - Series MM [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage17Member" xlink:to="msex_FirstMortgage17Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_FirstMortgage17Member_2_lbl" xml:lang="en-US">First Mortgage Bonds - Series NN [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage18Member" xlink:to="msex_FirstMortgage18Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_FirstMortgage18Member_2_lbl" xml:lang="en-US">First Mortgage Bonds - Series OO [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage19Member" xlink:to="msex_FirstMortgage19Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_FirstMortgage19Member_2_lbl" xml:lang="en-US">First Mortgage Bonds - Series PP [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage20Member" xlink:to="msex_FirstMortgage20Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_FirstMortgage20Member_2_lbl" xml:lang="en-US">First Mortgage Bonds - Series QQ [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage21Member" xlink:to="msex_FirstMortgage21Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_FirstMortgage21Member_2_lbl" xml:lang="en-US">First Mortgage Bonds - Series RR [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage22Member" xlink:to="msex_FirstMortgage22Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_FirstMortgage22Member_2_lbl" xml:lang="en-US">First Mortgage Bonds - Series SS [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ConvertiblePreferredStockMember" xlink:to="us-gaap_ConvertiblePreferredStockMember_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_ConvertiblePreferredStockMember_2_lbl" xml:lang="en-US">Convertible Preferred Stock $7.00 Series</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ConvertiblePreferredStock1Member" xlink:to="msex_ConvertiblePreferredStock1Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_ConvertiblePreferredStock1Member_2_lbl" xml:lang="en-US">Convertible Preferred Stock $8.00 Series [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NonredeemablePreferredStockMember" xlink:to="us-gaap_NonredeemablePreferredStockMember_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_NonredeemablePreferredStockMember_2_lbl" xml:lang="en-US">Nonredeemable Preferred Stock $7.00 Series</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_NonredeemablePreferredStock1Member" xlink:to="msex_NonredeemablePreferredStock1Member_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_NonredeemablePreferredStock1Member_2_lbl" xml:lang="en-US">Nonredeemable Preferred Stock $4.75 Series [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_WastewaterCollectionMember" xlink:label="msex_WastewaterCollectionMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_WastewaterCollectionMember" xlink:to="msex_WastewaterCollectionMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_WastewaterCollectionMember_lbl" xml:lang="en-US">Wastewater Collection [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_PinelandsCompanyMember" xlink:label="msex_PinelandsCompanyMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PinelandsCompanyMember" xlink:to="msex_PinelandsCompanyMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_PinelandsCompanyMember_lbl" xml:lang="en-US">Pinelands Water Company [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_PinelandsWastewaterMember" xlink:label="msex_PinelandsWastewaterMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PinelandsWastewaterMember" xlink:to="msex_PinelandsWastewaterMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_PinelandsWastewaterMember_lbl" xml:lang="en-US">Pinelands Wastewater [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_TwinLakesMember" xlink:label="msex_TwinLakesMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_TwinLakesMember" xlink:to="msex_TwinLakesMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_TwinLakesMember_lbl" xml:lang="en-US">Twin Lakes [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_ConstructionLoanMember" xlink:label="msex_ConstructionLoanMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ConstructionLoanMember" xlink:to="msex_ConstructionLoanMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_ConstructionLoanMember_lbl" xml:lang="en-US">Construction Loan [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_TidewaterMember" xlink:label="msex_TidewaterMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_TidewaterMember" xlink:to="msex_TidewaterMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_TidewaterMember_lbl" xml:lang="en-US">Tidewater [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_StateRevolvingTrustNote10Member" xlink:label="msex_StateRevolvingTrustNote10Member" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_StateRevolvingTrustNote10Member" xlink:to="msex_StateRevolvingTrustNote10Member_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_StateRevolvingTrustNote10Member_lbl" xml:lang="en-US">State Revolving Trust Note, due February 1, 2036 [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_NewConstructionLoansMember" xlink:label="msex_NewConstructionLoansMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_NewConstructionLoansMember" xlink:to="msex_NewConstructionLoansMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_NewConstructionLoansMember_lbl" xml:lang="en-US">Construction Loans [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MutualFundMember" xlink:label="us-gaap_MutualFundMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_MutualFundMember" xlink:to="us-gaap_MutualFundMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_MutualFundMember_lbl" xml:lang="en-US">Mutual Funds [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MoneyMarketFundsMember" xlink:label="us-gaap_MoneyMarketFundsMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_MoneyMarketFundsMember" xlink:to="us-gaap_MoneyMarketFundsMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_MoneyMarketFundsMember_lbl" xml:lang="en-US">Money Market Funds [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_AllLongTermDebtMember" xlink:label="msex_AllLongTermDebtMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_AllLongTermDebtMember" xlink:to="msex_AllLongTermDebtMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_AllLongTermDebtMember_lbl" xml:lang="en-US">All Long-term Debt [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis" xlink:label="us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis" xlink:to="us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis_lbl" xml:lang="en-US">Major Types of Debt and Equity Securities [Axis]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_InvestmentTypeAxis" xlink:label="us-gaap_InvestmentTypeAxis" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_InvestmentTypeAxis" xlink:to="us-gaap_InvestmentTypeAxis_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_InvestmentTypeAxis_lbl" xml:lang="en-US">Investment Type [Axis]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CashAndCashEquivalentsMember" xlink:label="us-gaap_CashAndCashEquivalentsMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CashAndCashEquivalentsMember" xlink:to="us-gaap_CashAndCashEquivalentsMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CashAndCashEquivalentsMember_lbl" xml:lang="en-US">Cash [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ExchangeTradedFundsMember" xlink:label="us-gaap_ExchangeTradedFundsMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ExchangeTradedFundsMember" xlink:to="us-gaap_ExchangeTradedFundsMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ExchangeTradedFundsMember_lbl" xml:lang="en-US">Commodities [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_TaxPeriodAxis" xlink:label="us-gaap_TaxPeriodAxis" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_TaxPeriodAxis" xlink:to="us-gaap_TaxPeriodAxis_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_TaxPeriodAxis_lbl" xml:lang="en-US">Tax Period [Axis]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_TaxYear2014Member" xlink:label="us-gaap_TaxYear2014Member" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_TaxYear2014Member" xlink:to="us-gaap_TaxYear2014Member_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_TaxYear2014Member_lbl" xml:lang="en-US">Tax Year 2014 [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_SecuredDebt7April2Member" xlink:label="msex_SecuredDebt7April2Member" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_SecuredDebt7April2Member" xlink:to="msex_SecuredDebt7April2Member_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_SecuredDebt7April2Member_lbl" xml:lang="en-US">4.47%, Amortizing Secured Note, due April 20, 2040 [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_FirstMortgage27Member" xlink:label="msex_FirstMortgage27Member" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage27Member" xlink:to="msex_FirstMortgage27Member_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_FirstMortgage27Member_lbl" xml:lang="en-US">First Mortgage Bonds - Series XX [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_FirstMortgage28Member" xlink:label="msex_FirstMortgage28Member" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage28Member" xlink:to="msex_FirstMortgage28Member_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_FirstMortgage28Member_lbl" xml:lang="en-US">First Mortgage Bonds - Series YY [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredIncomeTaxChargesMember" xlink:label="us-gaap_DeferredIncomeTaxChargesMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredIncomeTaxChargesMember" xlink:to="us-gaap_DeferredIncomeTaxChargesMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DeferredIncomeTaxChargesMember_lbl" xml:lang="en-US">Deferred Income Taxes [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScenarioForecastMember" xlink:label="us-gaap_ScenarioForecastMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScenarioForecastMember" xlink:to="us-gaap_ScenarioForecastMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScenarioForecastMember_lbl" xml:lang="en-US">Scenario, Forecast [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_NewJerseyBoardOfPublicUtilitiesMember" xlink:label="msex_NewJerseyBoardOfPublicUtilitiesMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_NewJerseyBoardOfPublicUtilitiesMember" xlink:to="msex_NewJerseyBoardOfPublicUtilitiesMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_NewJerseyBoardOfPublicUtilitiesMember_lbl" xml:lang="en-US">New Jersey Board Of Public Utilities [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AuctionMarketPreferredSecuritiesStockSeriesAxis" xlink:label="us-gaap_AuctionMarketPreferredSecuritiesStockSeriesAxis" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AuctionMarketPreferredSecuritiesStockSeriesAxis" xlink:to="us-gaap_AuctionMarketPreferredSecuritiesStockSeriesAxis_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AuctionMarketPreferredSecuritiesStockSeriesAxis_lbl" xml:lang="en-US">Auction Market Preferred Securities, Stock Series [Axis]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_SeriesXXMember" xlink:label="msex_SeriesXXMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_SeriesXXMember" xlink:to="msex_SeriesXXMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_SeriesXXMember_lbl" xml:lang="en-US">Series XX [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_SeriesYYMember" xlink:label="msex_SeriesYYMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_SeriesYYMember" xlink:to="msex_SeriesYYMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_SeriesYYMember_lbl" xml:lang="en-US">Series YY [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_NewJerseyInfrastructureBankTwoMember" xlink:label="msex_NewJerseyInfrastructureBankTwoMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_NewJerseyInfrastructureBankTwoMember" xlink:to="msex_NewJerseyInfrastructureBankTwoMember_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_NewJerseyInfrastructureBankTwoMember_lbl" xml:lang="en-US">New Jersey Infrastructure Bank [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_DocumentAndEntityInformationAbstract" xlink:label="msex_DocumentAndEntityInformationAbstract" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DocumentAndEntityInformationAbstract" xlink:to="msex_DocumentAndEntityInformationAbstract_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_DocumentAndEntityInformationAbstract_lbl" xml:lang="en-US">Document And Entity Information [Abstract]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityRegistrantName" xlink:label="dei_EntityRegistrantName" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityRegistrantName" xlink:to="dei_EntityRegistrantName_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityRegistrantName_lbl" xml:lang="en-US">Entity Registrant Name</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityCentralIndexKey" xlink:label="dei_EntityCentralIndexKey" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityCentralIndexKey" xlink:to="dei_EntityCentralIndexKey_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityCentralIndexKey_lbl" xml:lang="en-US">Entity Central Index Key</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_DocumentType" xlink:label="dei_DocumentType" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_DocumentType" xlink:to="dei_DocumentType_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_DocumentType_lbl" xml:lang="en-US">Document Type</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_DocumentPeriodEndDate" xlink:label="dei_DocumentPeriodEndDate" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_DocumentPeriodEndDate" xlink:to="dei_DocumentPeriodEndDate_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_DocumentPeriodEndDate_lbl" xml:lang="en-US">Document Period End Date</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_AmendmentFlag" xlink:label="dei_AmendmentFlag" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_AmendmentFlag" xlink:to="dei_AmendmentFlag_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_AmendmentFlag_lbl" xml:lang="en-US">Amendment Flag</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_CurrentFiscalYearEndDate" xlink:label="dei_CurrentFiscalYearEndDate" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_CurrentFiscalYearEndDate" xlink:to="dei_CurrentFiscalYearEndDate_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_CurrentFiscalYearEndDate_lbl" xml:lang="en-US">Current Fiscal Year End Date</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityWellKnownSeasonedIssuer" xlink:label="dei_EntityWellKnownSeasonedIssuer" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityWellKnownSeasonedIssuer" xlink:to="dei_EntityWellKnownSeasonedIssuer_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityWellKnownSeasonedIssuer_lbl" xml:lang="en-US">Entity a Well-known Seasoned Issuer</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityVoluntaryFilers" xlink:label="dei_EntityVoluntaryFilers" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityVoluntaryFilers" xlink:to="dei_EntityVoluntaryFilers_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityVoluntaryFilers_lbl" xml:lang="en-US">Entity a Voluntary Filer</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityCurrentReportingStatus" xlink:label="dei_EntityCurrentReportingStatus" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityCurrentReportingStatus" xlink:to="dei_EntityCurrentReportingStatus_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityCurrentReportingStatus_lbl" xml:lang="en-US">Entity Reporting Status Current</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityFilerCategory" xlink:label="dei_EntityFilerCategory" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityFilerCategory" xlink:to="dei_EntityFilerCategory_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityFilerCategory_lbl" xml:lang="en-US">Entity Filer Category</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityPublicFloat" xlink:label="dei_EntityPublicFloat" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityPublicFloat" xlink:to="dei_EntityPublicFloat_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityPublicFloat_lbl" xml:lang="en-US">Entity Public Float</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_EntityClosingMarketPricePerShare" xlink:label="msex_EntityClosingMarketPricePerShare" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_EntityClosingMarketPricePerShare" xlink:to="msex_EntityClosingMarketPricePerShare_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_EntityClosingMarketPricePerShare_lbl" xml:lang="en-US">Entity Closing Market Price (per share)</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_EntityCommonStockSharesOutstanding" xlink:label="dei_EntityCommonStockSharesOutstanding" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_EntityCommonStockSharesOutstanding" xlink:to="dei_EntityCommonStockSharesOutstanding_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="dei_EntityCommonStockSharesOutstanding_lbl" xml:lang="en-US">Entity Common Stock, Shares Outstanding</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.sec.gov/dei/2014/dei-2014-01-31.xsd#dei_DocumentFiscalPeriodFocus" xlink:label="dei_DocumentFiscalPeriodFocus" />
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      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_OtherExpenses_lbl" xml:lang="en-US">Other Expense</link:label>
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      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PublicUtilitiesPropertyPlantAndEquipmentOtherPropertyPlantAndEquipment_lbl" xml:lang="en-US">General</link:label>
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      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PublicUtilitiesPropertyPlantAndEquipmentConstructionWorkInProgress_lbl" xml:lang="en-US">Construction Work in Progress</link:label>
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      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PublicUtilitiesPropertyPlantAndEquipmentPlantInService" xlink:to="us-gaap_PublicUtilitiesPropertyPlantAndEquipmentPlantInService_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_PublicUtilitiesPropertyPlantAndEquipmentPlantInService_lbl" xml:lang="en-US">TOTAL</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PublicUtilitiesPropertyPlantAndEquipmentAccumulatedDepreciation" xlink:label="us-gaap_PublicUtilitiesPropertyPlantAndEquipmentAccumulatedDepreciation" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PublicUtilitiesPropertyPlantAndEquipmentAccumulatedDepreciation" xlink:to="us-gaap_PublicUtilitiesPropertyPlantAndEquipmentAccumulatedDepreciation_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PublicUtilitiesPropertyPlantAndEquipmentAccumulatedDepreciation_lbl" xml:lang="en-US">Less Accumulated Depreciation</link:label>
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      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PublicUtilitiesPropertyPlantAndEquipmentNet" xlink:to="us-gaap_PublicUtilitiesPropertyPlantAndEquipmentNet_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_PublicUtilitiesPropertyPlantAndEquipmentNet_lbl" xml:lang="en-US">UTILITY PLANT - NET</link:label>
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      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AssetsCurrentAbstract" xlink:to="us-gaap_AssetsCurrentAbstract_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AssetsCurrentAbstract_lbl" xml:lang="en-US">CURRENT ASSETS:</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:to="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_lbl" xml:lang="en-US">Cash and Cash Equivalents</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AccountsReceivableNetCurrent" xlink:label="us-gaap_AccountsReceivableNetCurrent" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AccountsReceivableNetCurrent" xlink:to="us-gaap_AccountsReceivableNetCurrent_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AccountsReceivableNetCurrent_lbl" xml:lang="en-US">Accounts Receivable, net</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_UnbilledReceivablesCurrent" xlink:label="us-gaap_UnbilledReceivablesCurrent" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_UnbilledReceivablesCurrent" xlink:to="us-gaap_UnbilledReceivablesCurrent_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_UnbilledReceivablesCurrent_lbl" xml:lang="en-US">Unbilled Revenues</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxesReceivable" xlink:label="us-gaap_IncomeTaxesReceivable" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncomeTaxesReceivable" xlink:to="us-gaap_IncomeTaxesReceivable_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncomeTaxesReceivable_lbl" xml:lang="en-US">Federal Income Tax Refund Receivable</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PublicUtilitiesInventory" xlink:label="us-gaap_PublicUtilitiesInventory" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PublicUtilitiesInventory" xlink:to="us-gaap_PublicUtilitiesInventory_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PublicUtilitiesInventory_lbl" xml:lang="en-US">Materials and Supplies (at average cost)</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PrepaidExpenseCurrent" xlink:label="us-gaap_PrepaidExpenseCurrent" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PrepaidExpenseCurrent" xlink:to="us-gaap_PrepaidExpenseCurrent_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PrepaidExpenseCurrent_lbl" xml:lang="en-US">Prepayments</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AssetsCurrent" xlink:label="us-gaap_AssetsCurrent" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AssetsCurrent" xlink:to="us-gaap_AssetsCurrent_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_AssetsCurrent_lbl" xml:lang="en-US">TOTAL CURRENT ASSETS</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_DeferredChargesAndOtherAssetsAbstract" xlink:label="msex_DeferredChargesAndOtherAssetsAbstract" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DeferredChargesAndOtherAssetsAbstract" xlink:to="msex_DeferredChargesAndOtherAssetsAbstract_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_DeferredChargesAndOtherAssetsAbstract_lbl" xml:lang="en-US">DEFERRED CHARGES AND OTHER ASSETS:</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_UnamortizedDebtIssuanceExpense" xlink:label="us-gaap_UnamortizedDebtIssuanceExpense" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_UnamortizedDebtIssuanceExpense" xlink:to="us-gaap_UnamortizedDebtIssuanceExpense_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_UnamortizedDebtIssuanceExpense_lbl" xml:lang="en-US">Unamortized Debt Expense</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_PreliminarySurveyAndInvestigationCharges" xlink:label="msex_PreliminarySurveyAndInvestigationCharges" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PreliminarySurveyAndInvestigationCharges" xlink:to="msex_PreliminarySurveyAndInvestigationCharges_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_PreliminarySurveyAndInvestigationCharges_lbl" xml:lang="en-US">Preliminary Survey and Investigation Charges</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RegulatoryAssetsNoncurrent" xlink:label="us-gaap_RegulatoryAssetsNoncurrent" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RegulatoryAssetsNoncurrent" xlink:to="us-gaap_RegulatoryAssetsNoncurrent_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RegulatoryAssetsNoncurrent_lbl" xml:lang="en-US">Regulatory Assets</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_OperationsContractsDeveloperAndOtherReceivables" xlink:label="msex_OperationsContractsDeveloperAndOtherReceivables" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_OperationsContractsDeveloperAndOtherReceivables" xlink:to="msex_OperationsContractsDeveloperAndOtherReceivables_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_OperationsContractsDeveloperAndOtherReceivables_lbl" xml:lang="en-US">Operations Contracts, Developer and Other Receivables</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RestrictedCashAndCashEquivalentsNoncurrent" xlink:label="us-gaap_RestrictedCashAndCashEquivalentsNoncurrent" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RestrictedCashAndCashEquivalentsNoncurrent" xlink:to="us-gaap_RestrictedCashAndCashEquivalentsNoncurrent_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RestrictedCashAndCashEquivalentsNoncurrent_lbl" xml:lang="en-US">Restricted Cash</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_NonUtilityAssetsNet" xlink:label="msex_NonUtilityAssetsNet" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_NonUtilityAssetsNet" xlink:to="msex_NonUtilityAssetsNet_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_NonUtilityAssetsNet_lbl" xml:lang="en-US">Non-utility Assets - Net</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxesReceivableNoncurrent" xlink:label="us-gaap_IncomeTaxesReceivableNoncurrent" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncomeTaxesReceivableNoncurrent" xlink:to="us-gaap_IncomeTaxesReceivableNoncurrent_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncomeTaxesReceivableNoncurrent_lbl" xml:lang="en-US">Federal Income Tax Receivable</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherAssetsNoncurrent" xlink:label="us-gaap_OtherAssetsNoncurrent" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherAssetsNoncurrent" xlink:to="us-gaap_OtherAssetsNoncurrent_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OtherAssetsNoncurrent_lbl" xml:lang="en-US">Other</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_DeferredChargesAndOtherAssets" xlink:label="msex_DeferredChargesAndOtherAssets" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DeferredChargesAndOtherAssets" xlink:to="msex_DeferredChargesAndOtherAssets_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="msex_DeferredChargesAndOtherAssets_lbl" xml:lang="en-US">TOTAL DEFERRED CHARGES AND OTHER ASSETS</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_Assets" xlink:label="us-gaap_Assets" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_Assets" xlink:to="us-gaap_Assets_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_Assets_lbl" xml:lang="en-US">TOTAL ASSETS</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LiabilitiesAndStockholdersEquityAbstract" xlink:label="us-gaap_LiabilitiesAndStockholdersEquityAbstract" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LiabilitiesAndStockholdersEquityAbstract" xlink:to="us-gaap_LiabilitiesAndStockholdersEquityAbstract_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LiabilitiesAndStockholdersEquityAbstract_lbl" xml:lang="en-US">CAPITALIZATION AND LIABILITIES</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CapitalizationLongtermDebtAndEquityAbstract" xlink:label="us-gaap_CapitalizationLongtermDebtAndEquityAbstract" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CapitalizationLongtermDebtAndEquityAbstract" xlink:to="us-gaap_CapitalizationLongtermDebtAndEquityAbstract_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CapitalizationLongtermDebtAndEquityAbstract_lbl" xml:lang="en-US">CAPITALIZATION:</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CommonStockValue" xlink:label="us-gaap_CommonStockValue" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CommonStockValue" xlink:to="us-gaap_CommonStockValue_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CommonStockValue_lbl" xml:lang="en-US">Common Stock, No Par Value</link:label>
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      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RetainedEarningsAccumulatedDeficit_lbl" xml:lang="en-US">Retained Earnings</link:label>
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      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_TotalCommonEquity" xlink:to="msex_TotalCommonEquity_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="msex_TotalCommonEquity_lbl" xml:lang="en-US">TOTAL COMMON EQUITY</link:label>
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      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PreferredStockValue_lbl" xml:lang="en-US">Preferred Stock</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongTermDebtNoncurrent" xlink:label="us-gaap_LongTermDebtNoncurrent" />
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      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LongTermDebtNoncurrent_lbl" xml:lang="en-US">Long-term Debt</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CapitalizationLongtermDebtAndEquity" xlink:label="us-gaap_CapitalizationLongtermDebtAndEquity" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CapitalizationLongtermDebtAndEquity" xlink:to="us-gaap_CapitalizationLongtermDebtAndEquity_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_CapitalizationLongtermDebtAndEquity_lbl" xml:lang="en-US">TOTAL CAPITALIZATION</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LiabilitiesCurrentAbstract" xlink:label="us-gaap_LiabilitiesCurrentAbstract" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LiabilitiesCurrentAbstract" xlink:to="us-gaap_LiabilitiesCurrentAbstract_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LiabilitiesCurrentAbstract_lbl" xml:lang="en-US">CURRENT LIABILITIES:</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongTermDebtCurrent" xlink:label="us-gaap_LongTermDebtCurrent" />
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      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LongTermDebtCurrent_lbl" xml:lang="en-US">Current Portion of Long-term Debt</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NotesPayableCurrent" xlink:label="us-gaap_NotesPayableCurrent" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NotesPayableCurrent" xlink:to="us-gaap_NotesPayableCurrent_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NotesPayableCurrent_lbl" xml:lang="en-US">Notes Payable</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AccountsPayableCurrent" xlink:label="us-gaap_AccountsPayableCurrent" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AccountsPayableCurrent" xlink:to="us-gaap_AccountsPayableCurrent_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AccountsPayableCurrent_lbl" xml:lang="en-US">Accounts Payable</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AccruedIncomeTaxesCurrent" xlink:label="us-gaap_AccruedIncomeTaxesCurrent" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AccruedIncomeTaxesCurrent" xlink:to="us-gaap_AccruedIncomeTaxesCurrent_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AccruedIncomeTaxesCurrent_lbl" xml:lang="en-US">Accrued Taxes</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_InterestPayableCurrent" xlink:label="us-gaap_InterestPayableCurrent" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_InterestPayableCurrent" xlink:to="us-gaap_InterestPayableCurrent_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_InterestPayableCurrent_lbl" xml:lang="en-US">Accrued Interest</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredRevenueCurrent" xlink:label="us-gaap_DeferredRevenueCurrent" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredRevenueCurrent" xlink:to="us-gaap_DeferredRevenueCurrent_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DeferredRevenueCurrent_lbl" xml:lang="en-US">Unearned Revenues and Advanced Service Fees</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherLiabilitiesCurrent" xlink:label="us-gaap_OtherLiabilitiesCurrent" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherLiabilitiesCurrent" xlink:to="us-gaap_OtherLiabilitiesCurrent_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_OtherLiabilitiesCurrent_lbl" xml:lang="en-US">Other</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LiabilitiesCurrent" xlink:label="us-gaap_LiabilitiesCurrent" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LiabilitiesCurrent" xlink:to="us-gaap_LiabilitiesCurrent_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_LiabilitiesCurrent_lbl" xml:lang="en-US">TOTAL CURRENT LIABILITIES</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CommitmentsAndContingencies" xlink:label="us-gaap_CommitmentsAndContingencies" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CommitmentsAndContingencies" xlink:to="us-gaap_CommitmentsAndContingencies_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CommitmentsAndContingencies_lbl" xml:lang="en-US">COMMITMENTS AND CONTINGENT LIABILITIES (Note 4)</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LiabilitiesOtherThanLongTermDebtNoncurrentAbstract" xlink:label="us-gaap_LiabilitiesOtherThanLongTermDebtNoncurrentAbstract" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LiabilitiesOtherThanLongTermDebtNoncurrentAbstract" xlink:to="us-gaap_LiabilitiesOtherThanLongTermDebtNoncurrentAbstract_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LiabilitiesOtherThanLongTermDebtNoncurrentAbstract_lbl" xml:lang="en-US">DEFERRED CREDITS AND OTHER LIABILITIES:</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CustomerAdvancesForConstruction" xlink:label="us-gaap_CustomerAdvancesForConstruction" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CustomerAdvancesForConstruction" xlink:to="us-gaap_CustomerAdvancesForConstruction_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CustomerAdvancesForConstruction_lbl" xml:lang="en-US">Customer Advances for Construction</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AccumulatedDeferredInvestmentTaxCredit" xlink:label="us-gaap_AccumulatedDeferredInvestmentTaxCredit" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AccumulatedDeferredInvestmentTaxCredit" xlink:to="us-gaap_AccumulatedDeferredInvestmentTaxCredit_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AccumulatedDeferredInvestmentTaxCredit_lbl" xml:lang="en-US">Accumulated Deferred Investment Tax Credits</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredTaxLiabilitiesNoncurrent" xlink:label="us-gaap_DeferredTaxLiabilitiesNoncurrent" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredTaxLiabilitiesNoncurrent" xlink:to="us-gaap_DeferredTaxLiabilitiesNoncurrent_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DeferredTaxLiabilitiesNoncurrent_lbl" xml:lang="en-US">Accumulated Deferred Income Taxes</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent" xlink:label="us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent" xlink:to="us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent_lbl" xml:lang="en-US">Employee Benefit Plans</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RegulatoryLiabilityNoncurrent" xlink:label="us-gaap_RegulatoryLiabilityNoncurrent" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RegulatoryLiabilityNoncurrent" xlink:to="us-gaap_RegulatoryLiabilityNoncurrent_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RegulatoryLiabilityNoncurrent_lbl" xml:lang="en-US">Regulatory Liabilities</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherLiabilitiesNoncurrent" xlink:label="us-gaap_OtherLiabilitiesNoncurrent" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherLiabilitiesNoncurrent" xlink:to="us-gaap_OtherLiabilitiesNoncurrent_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_OtherLiabilitiesNoncurrent_lbl" xml:lang="en-US">Other</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LiabilitiesOtherThanLongtermDebtNoncurrent" xlink:label="us-gaap_LiabilitiesOtherThanLongtermDebtNoncurrent" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LiabilitiesOtherThanLongtermDebtNoncurrent" xlink:to="us-gaap_LiabilitiesOtherThanLongtermDebtNoncurrent_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_LiabilitiesOtherThanLongtermDebtNoncurrent_lbl" xml:lang="en-US">TOTAL DEFERRED CREDITS AND OTHER LIABILITIES</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ContributionsInAidOfConstruction" xlink:label="us-gaap_ContributionsInAidOfConstruction" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ContributionsInAidOfConstruction" xlink:to="us-gaap_ContributionsInAidOfConstruction_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ContributionsInAidOfConstruction_lbl" xml:lang="en-US">CONTRIBUTIONS IN AID OF CONSTRUCTION</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LiabilitiesAndStockholdersEquity" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LiabilitiesAndStockholdersEquity" xlink:to="us-gaap_LiabilitiesAndStockholdersEquity_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity_lbl" xml:lang="en-US">TOTAL CAPITALIZATION AND LIABILITIES</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementOfCashFlowsAbstract" xlink:label="us-gaap_StatementOfCashFlowsAbstract" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StatementOfCashFlowsAbstract" xlink:to="us-gaap_StatementOfCashFlowsAbstract_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StatementOfCashFlowsAbstract_lbl" xml:lang="en-US">Statement of Cash Flows [Abstract]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract" xlink:to="us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NetCashProvidedByUsedInOperatingActivitiesContinuingOperationsAbstract_lbl" xml:lang="en-US">CASH FLOWS FROM OPERATING ACTIVITIES:</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetIncomeLoss" xlink:to="us-gaap_NetIncomeLoss_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NetIncomeLoss_2_lbl" xml:lang="en-US">Net Income</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" xlink:label="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract" xlink:to="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AdjustmentsToReconcileNetIncomeLossToCashProvidedByUsedInOperatingActivitiesAbstract_lbl" xml:lang="en-US">Adjustments to Reconcile Net Income to Net Cash Provided by Operating Activities:</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DepreciationDepletionAndAmortization" xlink:label="us-gaap_DepreciationDepletionAndAmortization" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DepreciationDepletionAndAmortization" xlink:to="us-gaap_DepreciationDepletionAndAmortization_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DepreciationDepletionAndAmortization_lbl" xml:lang="en-US">Depreciation and Amortization</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredIncomeTaxExpenseBenefit" xlink:label="us-gaap_DeferredIncomeTaxExpenseBenefit" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredIncomeTaxExpenseBenefit" xlink:to="us-gaap_DeferredIncomeTaxExpenseBenefit_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DeferredIncomeTaxExpenseBenefit_lbl" xml:lang="en-US">Provision for Deferred Income Taxes</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity" xlink:label="us-gaap_PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity" xlink:to="us-gaap_PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity_lbl" xml:lang="en-US">Equity Portion of Allowance For Funds Used During Construction (AFUDC)</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LifeInsuranceCorporateOrBankOwnedChangeInValue" xlink:label="us-gaap_LifeInsuranceCorporateOrBankOwnedChangeInValue" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LifeInsuranceCorporateOrBankOwnedChangeInValue" xlink:to="us-gaap_LifeInsuranceCorporateOrBankOwnedChangeInValue_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_LifeInsuranceCorporateOrBankOwnedChangeInValue_lbl" xml:lang="en-US">Cash Surrender Value of Life Insurance</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensation" xlink:label="us-gaap_ShareBasedCompensation" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensation" xlink:to="us-gaap_ShareBasedCompensation_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ShareBasedCompensation_lbl" xml:lang="en-US">Stock Compensation Expense</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_UtilitiesOperatingExpenseMaintenance" xlink:label="us-gaap_UtilitiesOperatingExpenseMaintenance" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_UtilitiesOperatingExpenseMaintenance" xlink:to="us-gaap_UtilitiesOperatingExpenseMaintenance_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_UtilitiesOperatingExpenseMaintenance_lbl" xml:lang="en-US">Adoption of Repairs on Tangible Property Regulations Net</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xlink:label="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xlink:to="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_lbl" xml:lang="en-US">Changes in Assets and Liabilities:</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncreaseDecreaseInAccountsReceivable" xlink:label="us-gaap_IncreaseDecreaseInAccountsReceivable" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInAccountsReceivable" xlink:to="us-gaap_IncreaseDecreaseInAccountsReceivable_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_IncreaseDecreaseInAccountsReceivable_lbl" xml:lang="en-US">Accounts Receivable</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncreaseDecreaseInUnbilledReceivables" xlink:label="us-gaap_IncreaseDecreaseInUnbilledReceivables" />
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      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_IncreaseDecreaseInUnbilledReceivables_lbl" xml:lang="en-US">Unbilled Revenues</link:label>
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      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_2_lbl" xml:lang="en-US">CASH AND CASH EQUIVALENTS AT BEGINNING OF PERIOD</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CashAndCashEquivalentsAtCarryingValue" xlink:to="us-gaap_CashAndCashEquivalentsAtCarryingValue_3_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="us-gaap_CashAndCashEquivalentsAtCarryingValue_3_lbl" xml:lang="en-US">CASH AND CASH EQUIVALENTS AT END OF PERIOD</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NoncashInvestingAndFinancingItemsAbstract" xlink:label="us-gaap_NoncashInvestingAndFinancingItemsAbstract" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NoncashInvestingAndFinancingItemsAbstract" xlink:to="us-gaap_NoncashInvestingAndFinancingItemsAbstract_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NoncashInvestingAndFinancingItemsAbstract_lbl" xml:lang="en-US">SUPPLEMENTAL DISCLOSURE OF NON-CASH ACTIVITY:</link:label>
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      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ContributionOfProperty" xlink:to="us-gaap_ContributionOfProperty_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ContributionOfProperty_lbl" xml:lang="en-US">Utility Plant received as Construction Advances and Contributions</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_DeobligatedPrincipalPayments" xlink:label="msex_DeobligatedPrincipalPayments" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DeobligatedPrincipalPayments" xlink:to="msex_DeobligatedPrincipalPayments_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_DeobligatedPrincipalPayments_lbl" xml:lang="en-US">Long-term Debt Deobligation</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SupplementalCashFlowInformationAbstract" xlink:label="us-gaap_SupplementalCashFlowInformationAbstract" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SupplementalCashFlowInformationAbstract" xlink:to="us-gaap_SupplementalCashFlowInformationAbstract_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SupplementalCashFlowInformationAbstract_lbl" xml:lang="en-US">SUPPLEMENTAL DISCLOSURE OF CASH FLOWS INFORMATION:</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_CashPaidDuringYearForAbstract" xlink:label="msex_CashPaidDuringYearForAbstract" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_CashPaidDuringYearForAbstract" xlink:to="msex_CashPaidDuringYearForAbstract_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_CashPaidDuringYearForAbstract_lbl" xml:lang="en-US">Cash Paid During the Year for:</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_InterestPaidNet" xlink:label="us-gaap_InterestPaidNet" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_InterestPaidNet" xlink:to="us-gaap_InterestPaidNet_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_InterestPaidNet_lbl" xml:lang="en-US">Interest</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_InterestPaidCapitalized" xlink:label="us-gaap_InterestPaidCapitalized" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_InterestPaidCapitalized" xlink:to="us-gaap_InterestPaidCapitalized_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_InterestPaidCapitalized_lbl" xml:lang="en-US">Interest Capitalized</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxesPaidNet" xlink:label="us-gaap_IncomeTaxesPaidNet" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncomeTaxesPaidNet" xlink:to="us-gaap_IncomeTaxesPaidNet_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_IncomeTaxesPaidNet_lbl" xml:lang="en-US">Income Taxes</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AllowanceForFundsUsedDuringConstructionInvestingActivities" xlink:label="us-gaap_AllowanceForFundsUsedDuringConstructionInvestingActivities" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AllowanceForFundsUsedDuringConstructionInvestingActivities" xlink:to="us-gaap_AllowanceForFundsUsedDuringConstructionInvestingActivities_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AllowanceForFundsUsedDuringConstructionInvestingActivities_lbl" xml:lang="en-US">Allowance for funds used during construction</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementTable" xlink:label="us-gaap_StatementTable" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StatementTable" xlink:to="us-gaap_StatementTable_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StatementTable_lbl" xml:lang="en-US">Statement [Table]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StatementLineItems" xlink:label="us-gaap_StatementLineItems" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StatementLineItems" xlink:to="us-gaap_StatementLineItems_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StatementLineItems_lbl" xml:lang="en-US">Statement [Line Items]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_TotalCommonEquity" xlink:to="msex_TotalCommonEquity_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_TotalCommonEquity_2_lbl" xml:lang="en-US">TOTAL COMMON EQUITY</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PreferredStockValue" xlink:to="us-gaap_PreferredStockValue_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_PreferredStockValue_2_lbl" xml:lang="en-US">TOTAL PREFERRED STOCK</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongTermDebt" xlink:label="us-gaap_LongTermDebt" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LongTermDebt" xlink:to="us-gaap_LongTermDebt_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LongTermDebt_lbl" xml:lang="en-US">SUBTOTAL LONG-TERM DEBT</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentUnamortizedPremium" xlink:label="us-gaap_DebtInstrumentUnamortizedPremium" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DebtInstrumentUnamortizedPremium" xlink:to="us-gaap_DebtInstrumentUnamortizedPremium_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DebtInstrumentUnamortizedPremium_lbl" xml:lang="en-US">Add: Premium on Issuance of Long-term Debt</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentUnamortizedDiscount" xlink:label="us-gaap_DebtInstrumentUnamortizedDiscount" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DebtInstrumentUnamortizedDiscount" xlink:to="us-gaap_DebtInstrumentUnamortizedDiscount_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_DebtInstrumentUnamortizedDiscount_lbl" xml:lang="en-US">Less: Unamortized Debt Expense</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LongTermDebtCurrent" xlink:to="us-gaap_LongTermDebtCurrent_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_LongTermDebtCurrent_2_lbl" xml:lang="en-US">Less: Current Portion of Long-term Debt</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LongTermDebtNoncurrent" xlink:to="us-gaap_LongTermDebtNoncurrent_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_LongTermDebtNoncurrent_2_lbl" xml:lang="en-US">TOTAL LONG-TERM DEBT</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CommonStockSharesAuthorized" xlink:label="us-gaap_CommonStockSharesAuthorized" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CommonStockSharesAuthorized" xlink:to="us-gaap_CommonStockSharesAuthorized_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CommonStockSharesAuthorized_lbl" xml:lang="en-US">Common Stock, Shares Authorized</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CommonStockSharesOutstanding" xlink:label="us-gaap_CommonStockSharesOutstanding" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CommonStockSharesOutstanding" xlink:to="us-gaap_CommonStockSharesOutstanding_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CommonStockSharesOutstanding_lbl" xml:lang="en-US">Common Stock, Shares Outstanding</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PreferredStockSharesAuthorized" xlink:label="us-gaap_PreferredStockSharesAuthorized" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PreferredStockSharesAuthorized" xlink:to="us-gaap_PreferredStockSharesAuthorized_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PreferredStockSharesAuthorized_lbl" xml:lang="en-US">Preferred Stock, Shares Authorized</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PreferredStockSharesOutstanding" xlink:label="us-gaap_PreferredStockSharesOutstanding" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PreferredStockSharesOutstanding" xlink:to="us-gaap_PreferredStockSharesOutstanding_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PreferredStockSharesOutstanding_lbl" xml:lang="en-US">Preferred Stock, Shares Outstanding</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentMaturityDate" xlink:label="us-gaap_DebtInstrumentMaturityDate" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DebtInstrumentMaturityDate" xlink:to="us-gaap_DebtInstrumentMaturityDate_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DebtInstrumentMaturityDate_lbl" xml:lang="en-US">Due date of debt</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentInterestRateStatedPercentage" xlink:label="us-gaap_DebtInstrumentInterestRateStatedPercentage" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DebtInstrumentInterestRateStatedPercentage" xlink:to="us-gaap_DebtInstrumentInterestRateStatedPercentage_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DebtInstrumentInterestRateStatedPercentage_lbl" xml:lang="en-US">Interest rate</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_TotalCommonEquity" xlink:to="msex_TotalCommonEquity_3_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="msex_TotalCommonEquity_3_lbl" xml:lang="en-US">Balance</link:label>
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      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SharesOutstanding" xlink:to="us-gaap_SharesOutstanding_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="us-gaap_SharesOutstanding_lbl" xml:lang="en-US">Balance, shares</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueDividendReinvestmentPlan" xlink:label="us-gaap_StockIssuedDuringPeriodValueDividendReinvestmentPlan" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockIssuedDuringPeriodValueDividendReinvestmentPlan" xlink:to="us-gaap_StockIssuedDuringPeriodValueDividendReinvestmentPlan_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockIssuedDuringPeriodValueDividendReinvestmentPlan_lbl" xml:lang="en-US">Dividend Reinvestment &amp; Common Stock Purchase Plan</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesDividendReinvestmentPlan" xlink:label="us-gaap_StockIssuedDuringPeriodSharesDividendReinvestmentPlan" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockIssuedDuringPeriodSharesDividendReinvestmentPlan" xlink:to="us-gaap_StockIssuedDuringPeriodSharesDividendReinvestmentPlan_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockIssuedDuringPeriodSharesDividendReinvestmentPlan_lbl" xml:lang="en-US">Dividend Reinvestment &amp; Common Stock Purchase Plan, shares</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures" xlink:label="us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures" xlink:to="us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockIssuedDuringPeriodValueRestrictedStockAwardNetOfForfeitures_lbl" xml:lang="en-US">Restricted Stock Award, Net - Employees</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures" xlink:label="us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures" xlink:to="us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockIssuedDuringPeriodSharesRestrictedStockAwardNetOfForfeitures_lbl" xml:lang="en-US">Restricted Stock Award, Net - Employees, shares</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation" xlink:label="us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation" xlink:to="us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockIssuedDuringPeriodValueShareBasedCompensation_lbl" xml:lang="en-US">Stock Award - Board Of Directors</link:label>
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      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockIssuedDuringPeriodSharesShareBasedCompensation_lbl" xml:lang="en-US">Stock Award - Board Of Directors, shares</link:label>
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      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CommitmentsAndContingenciesDisclosureAbstract_lbl" xml:lang="en-US">Commitments and Contingencies Disclosure [Abstract]</link:label>
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      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_QuarterlyFinancialInformationTextBlock" xlink:label="us-gaap_QuarterlyFinancialInformationTextBlock" />
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      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_CustomersAdvancesForConstructionCacPolicyTextBlock_lbl" xml:lang="en-US">Customers' Advances for Construction (CAC)</link:label>
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      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ContributionsInAidOfConstructionCiacPolicyTextBlock" xlink:to="msex_ContributionsInAidOfConstructionCiacPolicyTextBlock_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_ContributionsInAidOfConstructionCiacPolicyTextBlock_lbl" xml:lang="en-US">Contributions in Aid of Construction (CIAC)</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AllowanceForFundsUsedDuringConstructionPolicy" xlink:label="us-gaap_AllowanceForFundsUsedDuringConstructionPolicy" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AllowanceForFundsUsedDuringConstructionPolicy" xlink:to="us-gaap_AllowanceForFundsUsedDuringConstructionPolicy_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AllowanceForFundsUsedDuringConstructionPolicy_lbl" xml:lang="en-US">Allowance for Funds Used During Construction (AFUDC)</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ReceivablesPolicyTextBlock" xlink:label="us-gaap_ReceivablesPolicyTextBlock" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ReceivablesPolicyTextBlock" xlink:to="us-gaap_ReceivablesPolicyTextBlock_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ReceivablesPolicyTextBlock_lbl" xml:lang="en-US">Accounts Receivable</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RevenueRecognitionPolicyTextBlock" xlink:label="us-gaap_RevenueRecognitionPolicyTextBlock" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RevenueRecognitionPolicyTextBlock" xlink:to="us-gaap_RevenueRecognitionPolicyTextBlock_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RevenueRecognitionPolicyTextBlock_lbl" xml:lang="en-US">Revenues</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredChargesPolicyTextBlock" xlink:label="us-gaap_DeferredChargesPolicyTextBlock" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredChargesPolicyTextBlock" xlink:to="us-gaap_DeferredChargesPolicyTextBlock_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DeferredChargesPolicyTextBlock_lbl" xml:lang="en-US">Unamortized Debt Expense and Premiums on Long-Term Debt</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxPolicyTextBlock" xlink:label="us-gaap_IncomeTaxPolicyTextBlock" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncomeTaxPolicyTextBlock" xlink:to="us-gaap_IncomeTaxPolicyTextBlock_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_IncomeTaxPolicyTextBlock_lbl" xml:lang="en-US">Income Taxes</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CashAndCashEquivalentsPolicyTextBlock" xlink:label="us-gaap_CashAndCashEquivalentsPolicyTextBlock" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CashAndCashEquivalentsPolicyTextBlock" xlink:to="us-gaap_CashAndCashEquivalentsPolicyTextBlock_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CashAndCashEquivalentsPolicyTextBlock_lbl" xml:lang="en-US">Statements of Cash Flows</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CashAndCashEquivalentsRestrictedCashAndCashEquivalentsPolicy" xlink:label="us-gaap_CashAndCashEquivalentsRestrictedCashAndCashEquivalentsPolicy" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CashAndCashEquivalentsRestrictedCashAndCashEquivalentsPolicy" xlink:to="us-gaap_CashAndCashEquivalentsRestrictedCashAndCashEquivalentsPolicy_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_CashAndCashEquivalentsRestrictedCashAndCashEquivalentsPolicy_lbl" xml:lang="en-US">Restricted Cash</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_UseOfEstimates" xlink:label="us-gaap_UseOfEstimates" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_UseOfEstimates" xlink:to="us-gaap_UseOfEstimates_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_UseOfEstimates_lbl" xml:lang="en-US">Use of Estimates</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock" xlink:label="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock" xlink:to="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NewAccountingPronouncementsPolicyPolicyTextBlock_lbl" xml:lang="en-US">Recent Accounting Pronouncements</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_RecentDevelopmentsPolicyTextBlock" xlink:label="msex_RecentDevelopmentsPolicyTextBlock" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_RecentDevelopmentsPolicyTextBlock" xlink:to="msex_RecentDevelopmentsPolicyTextBlock_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_RecentDevelopmentsPolicyTextBlock_lbl" xml:lang="en-US">Recent Developments</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_RangeOfDepreciationRatesTableTextBlock" xlink:label="msex_RangeOfDepreciationRatesTableTextBlock" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_RangeOfDepreciationRatesTableTextBlock" xlink:to="msex_RangeOfDepreciationRatesTableTextBlock_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_RangeOfDepreciationRatesTableTextBlock_lbl" xml:lang="en-US">Range of depreciation rates</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_AllowanceForFundsUsedDuringConstructionRatesTableTextBlock" xlink:label="msex_AllowanceForFundsUsedDuringConstructionRatesTableTextBlock" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_AllowanceForFundsUsedDuringConstructionRatesTableTextBlock" xlink:to="msex_AllowanceForFundsUsedDuringConstructionRatesTableTextBlock_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_AllowanceForFundsUsedDuringConstructionRatesTableTextBlock_lbl" xml:lang="en-US">Allowance for Funds Used During Construction Rates</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfRegulatoryAssetsTextBlock" xlink:label="us-gaap_ScheduleOfRegulatoryAssetsTextBlock" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfRegulatoryAssetsTextBlock" xlink:to="us-gaap_ScheduleOfRegulatoryAssetsTextBlock_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfRegulatoryAssetsTextBlock_lbl" xml:lang="en-US">Schedule of regulatory assets</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock" xlink:label="us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock" xlink:to="us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock_lbl" xml:lang="en-US">Income tax expense reconciliation</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock" xlink:label="us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock" xlink:to="us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfComponentsOfIncomeTaxExpenseBenefitTableTextBlock_lbl" xml:lang="en-US">Income tax expense</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock" xlink:label="us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock" xlink:to="us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfDeferredTaxAssetsAndLiabilitiesTableTextBlock_lbl" xml:lang="en-US">Deferred tax liability</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PurchaseCommitmentExcludingLongtermCommitmentTableTextBlock" xlink:label="us-gaap_PurchaseCommitmentExcludingLongtermCommitmentTableTextBlock" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PurchaseCommitmentExcludingLongtermCommitmentTableTextBlock" xlink:to="us-gaap_PurchaseCommitmentExcludingLongtermCommitmentTableTextBlock_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PurchaseCommitmentExcludingLongtermCommitmentTableTextBlock_lbl" xml:lang="en-US">Schedule of water cost purchased</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesTableTextBlock" xlink:label="us-gaap_ScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesTableTextBlock" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesTableTextBlock" xlink:to="us-gaap_ScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesTableTextBlock_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfFutureMinimumRentalPaymentsForOperatingLeasesTableTextBlock_lbl" xml:lang="en-US">Schedule of future minimum operating lease</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfShortTermDebtTextBlock" xlink:label="us-gaap_ScheduleOfShortTermDebtTextBlock" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfShortTermDebtTextBlock" xlink:to="us-gaap_ScheduleOfShortTermDebtTextBlock_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfShortTermDebtTextBlock_lbl" xml:lang="en-US">Schedule of information regarding short-term borrowings</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfMaturitiesOfLongTermDebtTableTextBlock" xlink:label="us-gaap_ScheduleOfMaturitiesOfLongTermDebtTableTextBlock" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfMaturitiesOfLongTermDebtTableTextBlock" xlink:to="us-gaap_ScheduleOfMaturitiesOfLongTermDebtTableTextBlock_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfMaturitiesOfLongTermDebtTableTextBlock_lbl" xml:lang="en-US">Schedule of maturities of long term debt</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock" xlink:label="us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock" xlink:to="us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfEarningsPerShareBasicAndDilutedTableTextBlock_lbl" xml:lang="en-US">Schedule of earnings per share</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_FairValueByBalanceSheetGroupingTextBlock" xlink:label="us-gaap_FairValueByBalanceSheetGroupingTextBlock" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_FairValueByBalanceSheetGroupingTextBlock" xlink:to="us-gaap_FairValueByBalanceSheetGroupingTextBlock_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_FairValueByBalanceSheetGroupingTextBlock_lbl" xml:lang="en-US">Schedule of carrying amount and estimated fair value of bonds</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfChangesInProjectedBenefitObligationsTableTextBlock" xlink:label="us-gaap_ScheduleOfChangesInProjectedBenefitObligationsTableTextBlock" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfChangesInProjectedBenefitObligationsTableTextBlock" xlink:to="us-gaap_ScheduleOfChangesInProjectedBenefitObligationsTableTextBlock_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfChangesInProjectedBenefitObligationsTableTextBlock_lbl" xml:lang="en-US">Change in projected benefit obligation and fair value of plan assets</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfAmountsRecognizedInBalanceSheetTableTextBlock" xlink:label="us-gaap_ScheduleOfAmountsRecognizedInBalanceSheetTableTextBlock" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfAmountsRecognizedInBalanceSheetTableTextBlock" xlink:to="us-gaap_ScheduleOfAmountsRecognizedInBalanceSheetTableTextBlock_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfAmountsRecognizedInBalanceSheetTableTextBlock_lbl" xml:lang="en-US">Amounts recognized in balance sheet</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfNetBenefitCostsTableTextBlock" xlink:label="us-gaap_ScheduleOfNetBenefitCostsTableTextBlock" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfNetBenefitCostsTableTextBlock" xlink:to="us-gaap_ScheduleOfNetBenefitCostsTableTextBlock_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfNetBenefitCostsTableTextBlock_lbl" xml:lang="en-US">Components of net benefit cost</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_AmountsExpectedToBeAmortizedFromRegulatoryAssetsTableTextBlock" xlink:label="msex_AmountsExpectedToBeAmortizedFromRegulatoryAssetsTableTextBlock" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_AmountsExpectedToBeAmortizedFromRegulatoryAssetsTableTextBlock" xlink:to="msex_AmountsExpectedToBeAmortizedFromRegulatoryAssetsTableTextBlock_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_AmountsExpectedToBeAmortizedFromRegulatoryAssetsTableTextBlock_lbl" xml:lang="en-US">Amounts expected to be amortized from regulatory assets</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfAssumptionsUsedTableTextBlock" xlink:label="us-gaap_ScheduleOfAssumptionsUsedTableTextBlock" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfAssumptionsUsedTableTextBlock" xlink:to="us-gaap_ScheduleOfAssumptionsUsedTableTextBlock_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfAssumptionsUsedTableTextBlock_lbl" xml:lang="en-US">Discount and compensation rates</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfEffectOfOnePercentagePointChangeInAssumedHealthCareCostTrendRatesTableTextBlock" xlink:label="us-gaap_ScheduleOfEffectOfOnePercentagePointChangeInAssumedHealthCareCostTrendRatesTableTextBlock" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfEffectOfOnePercentagePointChangeInAssumedHealthCareCostTrendRatesTableTextBlock" xlink:to="us-gaap_ScheduleOfEffectOfOnePercentagePointChangeInAssumedHealthCareCostTrendRatesTableTextBlock_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfEffectOfOnePercentagePointChangeInAssumedHealthCareCostTrendRatesTableTextBlock_lbl" xml:lang="en-US">Effect of One-Percentage-Point Change in Assumed Health Care Cost Trend Rates</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfExpectedBenefitPaymentsTableTextBlock" xlink:label="us-gaap_ScheduleOfExpectedBenefitPaymentsTableTextBlock" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfExpectedBenefitPaymentsTableTextBlock" xlink:to="us-gaap_ScheduleOfExpectedBenefitPaymentsTableTextBlock_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfExpectedBenefitPaymentsTableTextBlock_lbl" xml:lang="en-US">Expected benefit payments</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_AllocationOfPlanAssetsTableTextBlock" xlink:label="msex_AllocationOfPlanAssetsTableTextBlock" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_AllocationOfPlanAssetsTableTextBlock" xlink:to="msex_AllocationOfPlanAssetsTableTextBlock_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_AllocationOfPlanAssetsTableTextBlock_lbl" xml:lang="en-US">Allocation of plan assets</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfAllocationOfPlanAssetsTableTextBlock" xlink:label="us-gaap_ScheduleOfAllocationOfPlanAssetsTableTextBlock" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfAllocationOfPlanAssetsTableTextBlock" xlink:to="us-gaap_ScheduleOfAllocationOfPlanAssetsTableTextBlock_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfAllocationOfPlanAssetsTableTextBlock_lbl" xml:lang="en-US">Fair value of plan assets</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfSharebasedCompensationRestrictedStockAndRestrictedStockUnitsActivityTableTextBlock" xlink:label="us-gaap_ScheduleOfSharebasedCompensationRestrictedStockAndRestrictedStockUnitsActivityTableTextBlock" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfSharebasedCompensationRestrictedStockAndRestrictedStockUnitsActivityTableTextBlock" xlink:to="us-gaap_ScheduleOfSharebasedCompensationRestrictedStockAndRestrictedStockUnitsActivityTableTextBlock_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfSharebasedCompensationRestrictedStockAndRestrictedStockUnitsActivityTableTextBlock_lbl" xml:lang="en-US">Restricted stock plan</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock" xlink:to="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTextBlock_lbl" xml:lang="en-US">Schedule of Segment Reporting Information, by Segment</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfQuarterlyFinancialInformationTableTextBlock" xlink:label="us-gaap_ScheduleOfQuarterlyFinancialInformationTableTextBlock" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfQuarterlyFinancialInformationTableTextBlock" xlink:to="us-gaap_ScheduleOfQuarterlyFinancialInformationTableTextBlock_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfQuarterlyFinancialInformationTableTextBlock_lbl" xml:lang="en-US">Quarterly financial information</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_OrganizationSummaryOfSignificantAccountingPoliciesAndRecentDevelopmentsTable" xlink:label="msex_OrganizationSummaryOfSignificantAccountingPoliciesAndRecentDevelopmentsTable" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_OrganizationSummaryOfSignificantAccountingPoliciesAndRecentDevelopmentsTable" xlink:to="msex_OrganizationSummaryOfSignificantAccountingPoliciesAndRecentDevelopmentsTable_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_OrganizationSummaryOfSignificantAccountingPoliciesAndRecentDevelopmentsTable_lbl" xml:lang="en-US">Organization, Summary Of Significant Accounting Policies And Recent Developments [Table]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_OrganizationSummaryOfSignificantAccountingPoliciesAndRecentDevelopmentsLineItems" xlink:label="msex_OrganizationSummaryOfSignificantAccountingPoliciesAndRecentDevelopmentsLineItems" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_OrganizationSummaryOfSignificantAccountingPoliciesAndRecentDevelopmentsLineItems" xlink:to="msex_OrganizationSummaryOfSignificantAccountingPoliciesAndRecentDevelopmentsLineItems_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_OrganizationSummaryOfSignificantAccountingPoliciesAndRecentDevelopmentsLineItems_lbl" xml:lang="en-US">Organization, Summary Of Significant Accounting Policies And Recent Developments [Line Items]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ConcentrationRiskByBenchmarkAxis" xlink:label="us-gaap_ConcentrationRiskByBenchmarkAxis" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ConcentrationRiskByBenchmarkAxis" xlink:to="us-gaap_ConcentrationRiskByBenchmarkAxis_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ConcentrationRiskByBenchmarkAxis_lbl" xml:lang="en-US">Concentration Risk Benchmark [Axis]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_PercentVotingInterest" xlink:label="msex_PercentVotingInterest" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PercentVotingInterest" xlink:to="msex_PercentVotingInterest_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_PercentVotingInterest_lbl" xml:lang="en-US">Percent voting interest</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_PercentOfOperatingRevenues" xlink:label="msex_PercentOfOperatingRevenues" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PercentOfOperatingRevenues" xlink:to="msex_PercentOfOperatingRevenues_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_PercentOfOperatingRevenues_lbl" xml:lang="en-US">Percent of operating revenues</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_PercentOfTotalAssets" xlink:label="msex_PercentOfTotalAssets" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PercentOfTotalAssets" xlink:to="msex_PercentOfTotalAssets_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_PercentOfTotalAssets_lbl" xml:lang="en-US">Percent of total assets</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PropertyPlantAndEquipmentUsefulLife" xlink:label="us-gaap_PropertyPlantAndEquipmentUsefulLife" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PropertyPlantAndEquipmentUsefulLife" xlink:to="us-gaap_PropertyPlantAndEquipmentUsefulLife_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PropertyPlantAndEquipmentUsefulLife_lbl" xml:lang="en-US">Estimated useful lives of non-regulated fixed assets</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AllowanceForDoubtfulAccountsReceivable" xlink:label="us-gaap_AllowanceForDoubtfulAccountsReceivable" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AllowanceForDoubtfulAccountsReceivable" xlink:to="us-gaap_AllowanceForDoubtfulAccountsReceivable_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AllowanceForDoubtfulAccountsReceivable_lbl" xml:lang="en-US">Allowance for doubtful accounts</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ProvisionForDoubtfulAccounts" xlink:label="us-gaap_ProvisionForDoubtfulAccounts" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ProvisionForDoubtfulAccounts" xlink:to="us-gaap_ProvisionForDoubtfulAccounts_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ProvisionForDoubtfulAccounts_lbl" xml:lang="en-US">Bad debt expense</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs" xlink:label="us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs" xlink:to="us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AllowanceForDoubtfulAccountsReceivableWriteOffs_lbl" xml:lang="en-US">Write-offs</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PublicUtilitiesApprovedRateIncreaseDecreaseAmount" xlink:label="us-gaap_PublicUtilitiesApprovedRateIncreaseDecreaseAmount" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PublicUtilitiesApprovedRateIncreaseDecreaseAmount" xlink:to="us-gaap_PublicUtilitiesApprovedRateIncreaseDecreaseAmount_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PublicUtilitiesApprovedRateIncreaseDecreaseAmount_lbl" xml:lang="en-US">Approved increase in annual operating revenues</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_TermOfAgreement" xlink:label="msex_TermOfAgreement" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_TermOfAgreement" xlink:to="msex_TermOfAgreement_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_TermOfAgreement_lbl" xml:lang="en-US">Term of agreement</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PublicUtilitiesRequestedRateIncreaseDecreaseAmount" xlink:label="us-gaap_PublicUtilitiesRequestedRateIncreaseDecreaseAmount" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PublicUtilitiesRequestedRateIncreaseDecreaseAmount" xlink:to="us-gaap_PublicUtilitiesRequestedRateIncreaseDecreaseAmount_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PublicUtilitiesRequestedRateIncreaseDecreaseAmount_lbl" xml:lang="en-US">Originally filed increase in annual operating revenue</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShortTermInvestments" xlink:label="us-gaap_ShortTermInvestments" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShortTermInvestments" xlink:to="us-gaap_ShortTermInvestments_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ShortTermInvestments_lbl" xml:lang="en-US">Investment</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LoansReceivableNet" xlink:label="us-gaap_LoansReceivableNet" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LoansReceivableNet" xlink:to="us-gaap_LoansReceivableNet_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LoansReceivableNet_lbl" xml:lang="en-US">Loan to RGRME</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_AccountsAndNotesReceivableNet" xlink:label="us-gaap_AccountsAndNotesReceivableNet" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AccountsAndNotesReceivableNet" xlink:to="us-gaap_AccountsAndNotesReceivableNet_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AccountsAndNotesReceivableNet_lbl" xml:lang="en-US">Uncollectible notes receivable</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ImpairmentChargeOnReclassifiedAssets" xlink:label="us-gaap_ImpairmentChargeOnReclassifiedAssets" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ImpairmentChargeOnReclassifiedAssets" xlink:to="us-gaap_ImpairmentChargeOnReclassifiedAssets_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ImpairmentChargeOnReclassifiedAssets_lbl" xml:lang="en-US">Noncash impairment charge</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ConcentrationRiskPercentage1" xlink:label="us-gaap_ConcentrationRiskPercentage1" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ConcentrationRiskPercentage1" xlink:to="us-gaap_ConcentrationRiskPercentage1_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ConcentrationRiskPercentage1_lbl" xml:lang="en-US">Non-regulated segment, percentage</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_ReclassificationOfUnamortizedDebtExpenseDueToNewAccountingStandard" xlink:label="msex_ReclassificationOfUnamortizedDebtExpenseDueToNewAccountingStandard" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ReclassificationOfUnamortizedDebtExpenseDueToNewAccountingStandard" xlink:to="msex_ReclassificationOfUnamortizedDebtExpenseDueToNewAccountingStandard_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_ReclassificationOfUnamortizedDebtExpenseDueToNewAccountingStandard_lbl" xml:lang="en-US">Reclassification due to new accounting standard</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PublicUtilityPropertyPlantAndEquipmentTable" xlink:label="us-gaap_PublicUtilityPropertyPlantAndEquipmentTable" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PublicUtilityPropertyPlantAndEquipmentTable" xlink:to="us-gaap_PublicUtilityPropertyPlantAndEquipmentTable_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PublicUtilityPropertyPlantAndEquipmentTable_lbl" xml:lang="en-US">Public Utility, Property, Plant and Equipment [Table]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PublicUtilityPropertyPlantAndEquipmentLineItems" xlink:label="us-gaap_PublicUtilityPropertyPlantAndEquipmentLineItems" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PublicUtilityPropertyPlantAndEquipmentLineItems" xlink:to="us-gaap_PublicUtilityPropertyPlantAndEquipmentLineItems_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PublicUtilityPropertyPlantAndEquipmentLineItems_lbl" xml:lang="en-US">Public Utility, Property, Plant and Equipment [Line Items]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService" xlink:label="us-gaap_PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService" xlink:to="us-gaap_PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PublicUtilitiesPropertyPlantAndEquipmentDisclosureOfCompositeDepreciationRateForPlantsInService_lbl" xml:lang="en-US">Public Utilities, Property, Plant and Equipment, Disclosure of Composite Depreciation Rate for Plants in Service</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PublicUtilitiesAllowanceForFundsUsedDuringConstructionRate" xlink:label="us-gaap_PublicUtilitiesAllowanceForFundsUsedDuringConstructionRate" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PublicUtilitiesAllowanceForFundsUsedDuringConstructionRate" xlink:to="us-gaap_PublicUtilitiesAllowanceForFundsUsedDuringConstructionRate_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_PublicUtilitiesAllowanceForFundsUsedDuringConstructionRate_lbl" xml:lang="en-US">Allowance for Funds Used During Construction Rates</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfRegulatoryLiabilitiesTable" xlink:label="us-gaap_ScheduleOfRegulatoryLiabilitiesTable" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfRegulatoryLiabilitiesTable" xlink:to="us-gaap_ScheduleOfRegulatoryLiabilitiesTable_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfRegulatoryLiabilitiesTable_lbl" xml:lang="en-US">Schedule of Regulatory Liabilities [Table]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RegulatoryLiabilitiesLineItems" xlink:label="us-gaap_RegulatoryLiabilitiesLineItems" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RegulatoryLiabilitiesLineItems" xlink:to="us-gaap_RegulatoryLiabilitiesLineItems_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RegulatoryLiabilitiesLineItems_lbl" xml:lang="en-US">Regulatory Liabilities [Line Items]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_TariffRateToRecoverAdditionalAnnualCosts" xlink:label="msex_TariffRateToRecoverAdditionalAnnualCosts" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_TariffRateToRecoverAdditionalAnnualCosts" xlink:to="msex_TariffRateToRecoverAdditionalAnnualCosts_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_TariffRateToRecoverAdditionalAnnualCosts_lbl" xml:lang="en-US">Additional annual costs</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PublicUtilitiesApprovedRateIncreaseDecreasePercentage" xlink:label="us-gaap_PublicUtilitiesApprovedRateIncreaseDecreasePercentage" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PublicUtilitiesApprovedRateIncreaseDecreasePercentage" xlink:to="us-gaap_PublicUtilitiesApprovedRateIncreaseDecreasePercentage_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PublicUtilitiesApprovedRateIncreaseDecreasePercentage_lbl" xml:lang="en-US">Approved increase in annual operating revenue (percentage)</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PublicUtilitiesRequestedRateIncreaseDecreaseAmendedAmount" xlink:label="us-gaap_PublicUtilitiesRequestedRateIncreaseDecreaseAmendedAmount" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PublicUtilitiesRequestedRateIncreaseDecreaseAmendedAmount" xlink:to="us-gaap_PublicUtilitiesRequestedRateIncreaseDecreaseAmendedAmount_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PublicUtilitiesRequestedRateIncreaseDecreaseAmendedAmount_lbl" xml:lang="en-US">Amended filed increase in annual operating revenue</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_BaseRateAmount" xlink:label="msex_BaseRateAmount" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_BaseRateAmount" xlink:to="msex_BaseRateAmount_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_BaseRateAmount_lbl" xml:lang="en-US">Base rate amount</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PublicUtilitiesApprovedReturnOnEquityPercentage" xlink:label="us-gaap_PublicUtilitiesApprovedReturnOnEquityPercentage" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PublicUtilitiesApprovedReturnOnEquityPercentage" xlink:to="us-gaap_PublicUtilitiesApprovedReturnOnEquityPercentage_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PublicUtilitiesApprovedReturnOnEquityPercentage_lbl" xml:lang="en-US">Return on equity</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredRevenueRefundPayments1" xlink:label="us-gaap_DeferredRevenueRefundPayments1" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredRevenueRefundPayments1" xlink:to="us-gaap_DeferredRevenueRefundPayments1_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DeferredRevenueRefundPayments1_lbl" xml:lang="en-US">Refund of previously deferred revenues</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_ProjectedAnnualRevenue" xlink:label="msex_ProjectedAnnualRevenue" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ProjectedAnnualRevenue" xlink:to="msex_ProjectedAnnualRevenue_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_ProjectedAnnualRevenue_lbl" xml:lang="en-US">Projected annual revenue</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_ReimbursementsReceivedForPreliminarySurveyAndInvestigationCosts" xlink:label="msex_ReimbursementsReceivedForPreliminarySurveyAndInvestigationCosts" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ReimbursementsReceivedForPreliminarySurveyAndInvestigationCosts" xlink:to="msex_ReimbursementsReceivedForPreliminarySurveyAndInvestigationCosts_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_ReimbursementsReceivedForPreliminarySurveyAndInvestigationCosts_lbl" xml:lang="en-US">Reimbursements received for preliminary survey and investigation costs</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_GainLossOnContractTermination" xlink:label="us-gaap_GainLossOnContractTermination" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_GainLossOnContractTermination" xlink:to="us-gaap_GainLossOnContractTermination_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_GainLossOnContractTermination_lbl" xml:lang="en-US">Gain on relinguishment of CPNC</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PublicUtilitiesDisclosureOfRateMatters" xlink:label="us-gaap_PublicUtilitiesDisclosureOfRateMatters" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PublicUtilitiesDisclosureOfRateMatters" xlink:to="us-gaap_PublicUtilitiesDisclosureOfRateMatters_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PublicUtilitiesDisclosureOfRateMatters_lbl" xml:lang="en-US">Description of application request seeking increase in base rates</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_BaseRateIncrease" xlink:label="msex_BaseRateIncrease" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_BaseRateIncrease" xlink:to="msex_BaseRateIncrease_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_BaseRateIncrease_lbl" xml:lang="en-US">Increase in base rates revenue per year</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_IncreaseInBaseRatesRevenuePerYearPercent" xlink:label="msex_IncreaseInBaseRatesRevenuePerYearPercent" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_IncreaseInBaseRatesRevenuePerYearPercent" xlink:to="msex_IncreaseInBaseRatesRevenuePerYearPercent_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_IncreaseInBaseRatesRevenuePerYearPercent_lbl" xml:lang="en-US">Increase in base rates revenue per year, percent</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_OriginallyFiledBaseWaterRateIncrease" xlink:label="msex_OriginallyFiledBaseWaterRateIncrease" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_OriginallyFiledBaseWaterRateIncrease" xlink:to="msex_OriginallyFiledBaseWaterRateIncrease_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_OriginallyFiledBaseWaterRateIncrease_lbl" xml:lang="en-US">Originally filed base water rate increase</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_RateBase" xlink:label="msex_RateBase" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_RateBase" xlink:to="msex_RateBase_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_RateBase_lbl" xml:lang="en-US">Return on invested capital, rate base</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_InterimRates" xlink:label="msex_InterimRates" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_InterimRates" xlink:to="msex_InterimRates_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_InterimRates_lbl" xml:lang="en-US">Interim rates</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_NumberOfCustomers" xlink:label="msex_NumberOfCustomers" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_NumberOfCustomers" xlink:to="msex_NumberOfCustomers_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_NumberOfCustomers_lbl" xml:lang="en-US">Number of customers</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_DsicRateIncrease" xlink:label="msex_DsicRateIncrease" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DsicRateIncrease" xlink:to="msex_DsicRateIncrease_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_DsicRateIncrease_lbl" xml:lang="en-US">DSIC rate increase</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_MaximumAnnualRevenuesAllowedUnderFoundationalFiling" xlink:label="msex_MaximumAnnualRevenuesAllowedUnderFoundationalFiling" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_MaximumAnnualRevenuesAllowedUnderFoundationalFiling" xlink:to="msex_MaximumAnnualRevenuesAllowedUnderFoundationalFiling_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_MaximumAnnualRevenuesAllowedUnderFoundationalFiling_lbl" xml:lang="en-US">Maximum annual revenues allowed under Foundational Filing</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_AcquisitionPremiums" xlink:label="msex_AcquisitionPremiums" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_AcquisitionPremiums" xlink:to="msex_AcquisitionPremiums_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_AcquisitionPremiums_lbl" xml:lang="en-US">Acquisition premiums</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_PurchaseOfWastewaterUtilityAssets" xlink:label="msex_PurchaseOfWastewaterUtilityAssets" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PurchaseOfWastewaterUtilityAssets" xlink:to="msex_PurchaseOfWastewaterUtilityAssets_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_PurchaseOfWastewaterUtilityAssets_lbl" xml:lang="en-US">Purchase of the wastewater utility assets</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_SuperstormSandyRelatedCosts" xlink:label="msex_SuperstormSandyRelatedCosts" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_SuperstormSandyRelatedCosts" xlink:to="msex_SuperstormSandyRelatedCosts_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_SuperstormSandyRelatedCosts_lbl" xml:lang="en-US">Superstorm sandy related costs</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_InitialPaymentReceivedFromInsuranceClaim" xlink:label="msex_InitialPaymentReceivedFromInsuranceClaim" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_InitialPaymentReceivedFromInsuranceClaim" xlink:to="msex_InitialPaymentReceivedFromInsuranceClaim_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_InitialPaymentReceivedFromInsuranceClaim_lbl" xml:lang="en-US">Initial payment received from insurance claim</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RegulatoryLiabilityNoncurrent" xlink:to="us-gaap_RegulatoryLiabilityNoncurrent_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_RegulatoryLiabilityNoncurrent_2_lbl" xml:lang="en-US">Regulatory Liability - Cost of Utility Plant Removal</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherDeferredCostsNet" xlink:label="us-gaap_OtherDeferredCostsNet" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherDeferredCostsNet" xlink:to="us-gaap_OtherDeferredCostsNet_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OtherDeferredCostsNet_lbl" xml:lang="en-US">Acquisition premiums to be recovered</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate" xlink:to="us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_EffectiveIncomeTaxRateReconciliationAtFederalStatutoryIncomeTaxRate_lbl" xml:lang="en-US">Corporate tax rate</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_PercentageOfCorporateTaxRegulatedCompainesPretax" xlink:label="msex_PercentageOfCorporateTaxRegulatedCompainesPretax" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PercentageOfCorporateTaxRegulatedCompainesPretax" xlink:to="msex_PercentageOfCorporateTaxRegulatedCompainesPretax_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_PercentageOfCorporateTaxRegulatedCompainesPretax_lbl" xml:lang="en-US">Percentage of corporate tax regulated compaines pre-tax</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RegulatoryLiabilities" xlink:label="us-gaap_RegulatoryLiabilities" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RegulatoryLiabilities" xlink:to="us-gaap_RegulatoryLiabilities_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RegulatoryLiabilities_lbl" xml:lang="en-US">Regulatory liabilities</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncreaseDecreaseInOtherRegulatoryAssets" xlink:label="us-gaap_IncreaseDecreaseInOtherRegulatoryAssets" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInOtherRegulatoryAssets" xlink:to="us-gaap_IncreaseDecreaseInOtherRegulatoryAssets_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncreaseDecreaseInOtherRegulatoryAssets_lbl" xml:lang="en-US">Decrease in Regulatory assets</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfRegulatoryAssetsTable" xlink:label="us-gaap_ScheduleOfRegulatoryAssetsTable" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfRegulatoryAssetsTable" xlink:to="us-gaap_ScheduleOfRegulatoryAssetsTable_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfRegulatoryAssetsTable_lbl" xml:lang="en-US">Schedule of Regulatory Assets [Table]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RegulatoryAssetLineItems" xlink:label="us-gaap_RegulatoryAssetLineItems" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RegulatoryAssetLineItems" xlink:to="us-gaap_RegulatoryAssetLineItems_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RegulatoryAssetLineItems_lbl" xml:lang="en-US">Regulatory Assets [Line Items]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RegulatoryAssets" xlink:label="us-gaap_RegulatoryAssets" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RegulatoryAssets" xlink:to="us-gaap_RegulatoryAssets_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_RegulatoryAssets_lbl" xml:lang="en-US">Regulatory Assets</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_RemainingRecoveryPeriod" xlink:label="msex_RemainingRecoveryPeriod" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_RemainingRecoveryPeriod" xlink:to="msex_RemainingRecoveryPeriod_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_RemainingRecoveryPeriod_lbl" xml:lang="en-US">Remaining recovery period</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate" xlink:label="us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate" xlink:to="us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncomeTaxReconciliationIncomeTaxExpenseBenefitAtFederalStatutoryIncomeTaxRate_lbl" xml:lang="en-US">Income Tax at Statutory Rate</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_TaxEffectOfAbstract" xlink:label="msex_TaxEffectOfAbstract" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_TaxEffectOfAbstract" xlink:to="msex_TaxEffectOfAbstract_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_TaxEffectOfAbstract_lbl" xml:lang="en-US">Tax Effect of:</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxReconciliationDispositionOfAssets" xlink:label="us-gaap_IncomeTaxReconciliationDispositionOfAssets" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncomeTaxReconciliationDispositionOfAssets" xlink:to="us-gaap_IncomeTaxReconciliationDispositionOfAssets_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncomeTaxReconciliationDispositionOfAssets_lbl" xml:lang="en-US">Utility Plant Related</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxReconciliationStateAndLocalIncomeTaxes" xlink:label="us-gaap_IncomeTaxReconciliationStateAndLocalIncomeTaxes" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncomeTaxReconciliationStateAndLocalIncomeTaxes" xlink:to="us-gaap_IncomeTaxReconciliationStateAndLocalIncomeTaxes_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncomeTaxReconciliationStateAndLocalIncomeTaxes_lbl" xml:lang="en-US">State Income Taxes - Net</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxReconciliationTaxCreditsOther" xlink:label="us-gaap_IncomeTaxReconciliationTaxCreditsOther" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncomeTaxReconciliationTaxCreditsOther" xlink:to="us-gaap_IncomeTaxReconciliationTaxCreditsOther_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_IncomeTaxReconciliationTaxCreditsOther_lbl" xml:lang="en-US">Tax Act</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_EmployeeBenefits" xlink:label="msex_EmployeeBenefits" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_EmployeeBenefits" xlink:to="msex_EmployeeBenefits_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_EmployeeBenefits_lbl" xml:lang="en-US">Employee Benefits</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxReconciliationNondeductibleExpenseOther" xlink:label="us-gaap_IncomeTaxReconciliationNondeductibleExpenseOther" />
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      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_IncomeTaxReconciliationNondeductibleExpenseOther_lbl" xml:lang="en-US">Other</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncomeTaxExpenseBenefit" xlink:to="us-gaap_IncomeTaxExpenseBenefit_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_IncomeTaxExpenseBenefit_2_lbl" xml:lang="en-US">Total Income Tax Expense</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_CurrentAbstract" xlink:label="msex_CurrentAbstract" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_CurrentAbstract" xlink:to="msex_CurrentAbstract_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_CurrentAbstract_lbl" xml:lang="en-US">Current:</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CurrentFederalTaxExpenseBenefit" xlink:label="us-gaap_CurrentFederalTaxExpenseBenefit" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CurrentFederalTaxExpenseBenefit" xlink:to="us-gaap_CurrentFederalTaxExpenseBenefit_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CurrentFederalTaxExpenseBenefit_lbl" xml:lang="en-US">Federal</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CurrentStateAndLocalTaxExpenseBenefit" xlink:label="us-gaap_CurrentStateAndLocalTaxExpenseBenefit" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CurrentStateAndLocalTaxExpenseBenefit" xlink:to="us-gaap_CurrentStateAndLocalTaxExpenseBenefit_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CurrentStateAndLocalTaxExpenseBenefit_lbl" xml:lang="en-US">State</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_DeferredAbstract" xlink:label="msex_DeferredAbstract" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DeferredAbstract" xlink:to="msex_DeferredAbstract_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_DeferredAbstract_lbl" xml:lang="en-US">Deferred:</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredFederalIncomeTaxExpenseBenefit" xlink:label="us-gaap_DeferredFederalIncomeTaxExpenseBenefit" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredFederalIncomeTaxExpenseBenefit" xlink:to="us-gaap_DeferredFederalIncomeTaxExpenseBenefit_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_DeferredFederalIncomeTaxExpenseBenefit_lbl" xml:lang="en-US">Federal</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit" xlink:label="us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit" xlink:to="us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_DeferredStateAndLocalIncomeTaxExpenseBenefit_lbl" xml:lang="en-US">State</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredOtherTaxExpenseBenefit" xlink:label="us-gaap_DeferredOtherTaxExpenseBenefit" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredOtherTaxExpenseBenefit" xlink:to="us-gaap_DeferredOtherTaxExpenseBenefit_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DeferredOtherTaxExpenseBenefit_lbl" xml:lang="en-US">Investment Tax Credits</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncomeTaxExpenseBenefit" xlink:to="us-gaap_IncomeTaxExpenseBenefit_3_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_IncomeTaxExpenseBenefit_3_lbl" xml:lang="en-US">Total Income Tax Expense</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_DeferredTaxLiabilitiesUtilityPlantRelated" xlink:label="msex_DeferredTaxLiabilitiesUtilityPlantRelated" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DeferredTaxLiabilitiesUtilityPlantRelated" xlink:to="msex_DeferredTaxLiabilitiesUtilityPlantRelated_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_DeferredTaxLiabilitiesUtilityPlantRelated_lbl" xml:lang="en-US">Utility Plant Related</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_DeferredTaxAssetsCustomerAdvances" xlink:label="msex_DeferredTaxAssetsCustomerAdvances" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DeferredTaxAssetsCustomerAdvances" xlink:to="msex_DeferredTaxAssetsCustomerAdvances_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="msex_DeferredTaxAssetsCustomerAdvances_lbl" xml:lang="en-US">Customer Advances</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredTaxLiabilitiesOther" xlink:label="us-gaap_DeferredTaxLiabilitiesOther" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredTaxLiabilitiesOther" xlink:to="us-gaap_DeferredTaxLiabilitiesOther_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_DeferredTaxLiabilitiesOther_lbl" xml:lang="en-US">Employee Benefits</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_DeferredTaxLiabilitiesInvestmentTaxCredits" xlink:label="msex_DeferredTaxLiabilitiesInvestmentTaxCredits" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DeferredTaxLiabilitiesInvestmentTaxCredits" xlink:to="msex_DeferredTaxLiabilitiesInvestmentTaxCredits_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_DeferredTaxLiabilitiesInvestmentTaxCredits_lbl" xml:lang="en-US">Investment Tax Credits (ITC)</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredTaxAssetsOperatingLossCarryforwards" xlink:label="us-gaap_DeferredTaxAssetsOperatingLossCarryforwards" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredTaxAssetsOperatingLossCarryforwards" xlink:to="us-gaap_DeferredTaxAssetsOperatingLossCarryforwards_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DeferredTaxAssetsOperatingLossCarryforwards_lbl" xml:lang="en-US">Net Operating Loss Carryforwards</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredTaxAssetsOther" xlink:label="us-gaap_DeferredTaxAssetsOther" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredTaxAssetsOther" xlink:to="us-gaap_DeferredTaxAssetsOther_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_DeferredTaxAssetsOther_lbl" xml:lang="en-US">Other</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DeferredTaxLiabilities" xlink:label="us-gaap_DeferredTaxLiabilities" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DeferredTaxLiabilities" xlink:to="us-gaap_DeferredTaxLiabilities_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_DeferredTaxLiabilities_lbl" xml:lang="en-US">Total Deferred Tax Liability and ITC</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncomeTaxReceivable" xlink:label="us-gaap_IncomeTaxReceivable" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncomeTaxReceivable" xlink:to="us-gaap_IncomeTaxReceivable_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncomeTaxReceivable_lbl" xml:lang="en-US">Income Taxes Receivable</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OperatingLossCarryforwardsTable" xlink:label="us-gaap_OperatingLossCarryforwardsTable" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OperatingLossCarryforwardsTable" xlink:to="us-gaap_OperatingLossCarryforwardsTable_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OperatingLossCarryforwardsTable_lbl" xml:lang="en-US">Operating Loss Carryforwards [Table]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OperatingLossCarryforwardsLineItems" xlink:label="us-gaap_OperatingLossCarryforwardsLineItems" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OperatingLossCarryforwardsLineItems" xlink:to="us-gaap_OperatingLossCarryforwardsLineItems_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OperatingLossCarryforwardsLineItems_lbl" xml:lang="en-US">Operating Loss Carryforwards [Line Items]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_TaxAdjustmentsSettlementsAndUnusualProvisions" xlink:label="us-gaap_TaxAdjustmentsSettlementsAndUnusualProvisions" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_TaxAdjustmentsSettlementsAndUnusualProvisions" xlink:to="us-gaap_TaxAdjustmentsSettlementsAndUnusualProvisions_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_TaxAdjustmentsSettlementsAndUnusualProvisions_lbl" xml:lang="en-US">Net reduction in taxes due to the federal government</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_ReserveAgainstTangiblePropertyDeductions" xlink:label="msex_ReserveAgainstTangiblePropertyDeductions" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ReserveAgainstTangiblePropertyDeductions" xlink:to="msex_ReserveAgainstTangiblePropertyDeductions_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_ReserveAgainstTangiblePropertyDeductions_lbl" xml:lang="en-US">Reserve against tangible property deductions</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OperatingLossCarryforwards" xlink:label="us-gaap_OperatingLossCarryforwards" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OperatingLossCarryforwards" xlink:to="us-gaap_OperatingLossCarryforwards_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OperatingLossCarryforwards_lbl" xml:lang="en-US">Operating loss carry-forward</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OperatingLossCarryforwardsExpirationDate" xlink:label="us-gaap_OperatingLossCarryforwardsExpirationDate" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OperatingLossCarryforwardsExpirationDate" xlink:to="us-gaap_OperatingLossCarryforwardsExpirationDate_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OperatingLossCarryforwardsExpirationDate_lbl" xml:lang="en-US">Net operating loss carry-forward, expiring</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncomeTaxReceivable" xlink:to="us-gaap_IncomeTaxReceivable_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_IncomeTaxReceivable_2_lbl" xml:lang="en-US">Income tax refund receivable</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_IncreaseDecreaseInDeferredIncomeTaxes" xlink:label="us-gaap_IncreaseDecreaseInDeferredIncomeTaxes" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInDeferredIncomeTaxes" xlink:to="us-gaap_IncreaseDecreaseInDeferredIncomeTaxes_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncreaseDecreaseInDeferredIncomeTaxes_lbl" xml:lang="en-US">Decreased deferred income tax expense</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_CommitmentAndContingenciesTable" xlink:label="msex_CommitmentAndContingenciesTable" />
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      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_CommitmentAndContingenciesTable_lbl" xml:lang="en-US">Commitment And Contingencies [Table]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_CommitmentAndContingenciesLineItems" xlink:label="msex_CommitmentAndContingenciesLineItems" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_CommitmentAndContingenciesLineItems" xlink:to="msex_CommitmentAndContingenciesLineItems_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_CommitmentAndContingenciesLineItems_lbl" xml:lang="en-US">Commitment And Contingencies [Line Items]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongtermPurchaseCommitmentPeriod" xlink:label="us-gaap_LongtermPurchaseCommitmentPeriod" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LongtermPurchaseCommitmentPeriod" xlink:to="us-gaap_LongtermPurchaseCommitmentPeriod_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LongtermPurchaseCommitmentPeriod_lbl" xml:lang="en-US">Period of wastewater agreement</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SignificantSupplyCommitmentDescription" xlink:label="us-gaap_SignificantSupplyCommitmentDescription" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SignificantSupplyCommitmentDescription" xlink:to="us-gaap_SignificantSupplyCommitmentDescription_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SignificantSupplyCommitmentDescription_lbl" xml:lang="en-US">Term of water and wastewater system agreement</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongTermPurchaseCommitmentDescription" xlink:label="us-gaap_LongTermPurchaseCommitmentDescription" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LongTermPurchaseCommitmentDescription" xlink:to="us-gaap_LongTermPurchaseCommitmentDescription_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LongTermPurchaseCommitmentDescription_lbl" xml:lang="en-US">Commitment of purchase of untreated water</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_MinimumTreatedWaterPurchaseCommitment" xlink:label="msex_MinimumTreatedWaterPurchaseCommitment" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_MinimumTreatedWaterPurchaseCommitment" xlink:to="msex_MinimumTreatedWaterPurchaseCommitment_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_MinimumTreatedWaterPurchaseCommitment_lbl" xml:lang="en-US">Minimum treated water purchase commitment</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_GuarantyLiabilities" xlink:label="us-gaap_GuarantyLiabilities" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_GuarantyLiabilities" xlink:to="us-gaap_GuarantyLiabilities_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_GuarantyLiabilities_lbl" xml:lang="en-US">Guarant liabilty for AWM's performance</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_BudgetedConstructionCost" xlink:label="msex_BudgetedConstructionCost" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_BudgetedConstructionCost" xlink:to="msex_BudgetedConstructionCost_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_BudgetedConstructionCost_lbl" xml:lang="en-US">Budgeted construction cost for construction program, 2018</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_BudgetedConstructionCostForConstructionProgramYearOne" xlink:label="msex_BudgetedConstructionCostForConstructionProgramYearOne" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_BudgetedConstructionCostForConstructionProgramYearOne" xlink:to="msex_BudgetedConstructionCostForConstructionProgramYearOne_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_BudgetedConstructionCostForConstructionProgramYearOne_lbl" xml:lang="en-US">Budgeted construction cost for construction program, 2019</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_BudgetedConstructionCostForConstructionProgramYearTwo" xlink:label="msex_BudgetedConstructionCostForConstructionProgramYearTwo" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_BudgetedConstructionCostForConstructionProgramYearTwo" xlink:to="msex_BudgetedConstructionCostForConstructionProgramYearTwo_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_BudgetedConstructionCostForConstructionProgramYearTwo_lbl" xml:lang="en-US">Budgeted construction cost for construction program, 2010</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_LongtermPurchaseCommitmentExpirationDate" xlink:label="msex_LongtermPurchaseCommitmentExpirationDate" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_LongtermPurchaseCommitmentExpirationDate" xlink:to="msex_LongtermPurchaseCommitmentExpirationDate_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_LongtermPurchaseCommitmentExpirationDate_lbl" xml:lang="en-US">Purchase commitment expiration date of contract</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongTermPurchaseCommitmentMinimumQuantityRequired" xlink:label="us-gaap_LongTermPurchaseCommitmentMinimumQuantityRequired" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LongTermPurchaseCommitmentMinimumQuantityRequired" xlink:to="us-gaap_LongTermPurchaseCommitmentMinimumQuantityRequired_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LongTermPurchaseCommitmentMinimumQuantityRequired_lbl" xml:lang="en-US">Water purchase per commitment</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LeaseAndRentalExpense" xlink:label="us-gaap_LeaseAndRentalExpense" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LeaseAndRentalExpense" xlink:to="us-gaap_LeaseAndRentalExpense_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LeaseAndRentalExpense_lbl" xml:lang="en-US">Rental expenses under operating leases</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LessorLeasingArrangementsOperatingLeasesRenewalTerm" xlink:label="us-gaap_LessorLeasingArrangementsOperatingLeasesRenewalTerm" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LessorLeasingArrangementsOperatingLeasesRenewalTerm" xlink:to="us-gaap_LessorLeasingArrangementsOperatingLeasesRenewalTerm_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LessorLeasingArrangementsOperatingLeasesRenewalTerm_lbl" xml:lang="en-US">Rental commitment under operating lease terms</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_CostOfPurchasedWaterAbstract" xlink:label="msex_CostOfPurchasedWaterAbstract" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_CostOfPurchasedWaterAbstract" xlink:to="msex_CostOfPurchasedWaterAbstract_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_CostOfPurchasedWaterAbstract_lbl" xml:lang="en-US">Purchased Water</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_CostOfUntreatedWater" xlink:label="msex_CostOfUntreatedWater" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_CostOfUntreatedWater" xlink:to="msex_CostOfUntreatedWater_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_CostOfUntreatedWater_lbl" xml:lang="en-US">Untreated</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_CostOfTreatedWater" xlink:label="msex_CostOfTreatedWater" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_CostOfTreatedWater" xlink:to="msex_CostOfTreatedWater_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_CostOfTreatedWater_lbl" xml:lang="en-US">Treated</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_CostOfPurchasedWater" xlink:label="us-gaap_CostOfPurchasedWater" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CostOfPurchasedWater" xlink:to="us-gaap_CostOfPurchasedWater_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_CostOfPurchasedWater_lbl" xml:lang="en-US">Total Costs</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_MinimumLeasePaymentsSaleLeasebackTransactionsAbstract" xlink:label="us-gaap_MinimumLeasePaymentsSaleLeasebackTransactionsAbstract" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_MinimumLeasePaymentsSaleLeasebackTransactionsAbstract" xlink:to="us-gaap_MinimumLeasePaymentsSaleLeasebackTransactionsAbstract_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_MinimumLeasePaymentsSaleLeasebackTransactionsAbstract_lbl" xml:lang="en-US">Minimum Lease Payments, Sale Leaseback Transactions, Fiscal Year Maturity [Abstract]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent" xlink:to="us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDueCurrent_lbl" xml:lang="en-US">2018</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears" xlink:to="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInTwoYears_lbl" xml:lang="en-US">2019</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears" xlink:to="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInThreeYears_lbl" xml:lang="en-US">2020</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears" xlink:to="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFourYears_lbl" xml:lang="en-US">2021</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFiveYears" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFiveYears" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFiveYears" xlink:to="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFiveYears_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDueInFiveYears_lbl" xml:lang="en-US">2022</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OperatingLeasesFutureMinimumPaymentsDue" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDue" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OperatingLeasesFutureMinimumPaymentsDue" xlink:to="us-gaap_OperatingLeasesFutureMinimumPaymentsDue_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OperatingLeasesFutureMinimumPaymentsDue_lbl" xml:lang="en-US">Thereafter</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LineOfCreditFacilityAbstract" xlink:label="us-gaap_LineOfCreditFacilityAbstract" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LineOfCreditFacilityAbstract" xlink:to="us-gaap_LineOfCreditFacilityAbstract_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LineOfCreditFacilityAbstract_lbl" xml:lang="en-US">Lines Of Credit Facility</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LineOfCreditFacilityMaximumMonthendOutstandingAmount" xlink:label="us-gaap_LineOfCreditFacilityMaximumMonthendOutstandingAmount" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LineOfCreditFacilityMaximumMonthendOutstandingAmount" xlink:to="us-gaap_LineOfCreditFacilityMaximumMonthendOutstandingAmount_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LineOfCreditFacilityMaximumMonthendOutstandingAmount_lbl" xml:lang="en-US">Established Lines at Year-End</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LineOfCreditFacilityMaximumAmountOutstandingDuringPeriod" xlink:label="us-gaap_LineOfCreditFacilityMaximumAmountOutstandingDuringPeriod" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LineOfCreditFacilityMaximumAmountOutstandingDuringPeriod" xlink:to="us-gaap_LineOfCreditFacilityMaximumAmountOutstandingDuringPeriod_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LineOfCreditFacilityMaximumAmountOutstandingDuringPeriod_lbl" xml:lang="en-US">Maximum Amount Outstanding</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LineOfCreditFacilityAverageOutstandingAmount" xlink:label="us-gaap_LineOfCreditFacilityAverageOutstandingAmount" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LineOfCreditFacilityAverageOutstandingAmount" xlink:to="us-gaap_LineOfCreditFacilityAverageOutstandingAmount_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LineOfCreditFacilityAverageOutstandingAmount_lbl" xml:lang="en-US">Average Outstanding</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShortTermBorrowings" xlink:label="us-gaap_ShortTermBorrowings" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShortTermBorrowings" xlink:to="us-gaap_ShortTermBorrowings_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="us-gaap_ShortTermBorrowings_lbl" xml:lang="en-US">Notes Payable at Year-End</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LineOfCreditFacilityInterestRateDuringPeriod" xlink:label="us-gaap_LineOfCreditFacilityInterestRateDuringPeriod" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LineOfCreditFacilityInterestRateDuringPeriod" xlink:to="us-gaap_LineOfCreditFacilityInterestRateDuringPeriod_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LineOfCreditFacilityInterestRateDuringPeriod_lbl" xml:lang="en-US">Weighted Average Interest Rate</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LineOfCreditFacilityInterestRateAtPeriodEnd" xlink:label="us-gaap_LineOfCreditFacilityInterestRateAtPeriodEnd" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LineOfCreditFacilityInterestRateAtPeriodEnd" xlink:to="us-gaap_LineOfCreditFacilityInterestRateAtPeriodEnd_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="us-gaap_LineOfCreditFacilityInterestRateAtPeriodEnd_lbl" xml:lang="en-US">Weighted Average Interest Rate at Year-End</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfCapitalizationTable" xlink:label="us-gaap_ScheduleOfCapitalizationTable" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfCapitalizationTable" xlink:to="us-gaap_ScheduleOfCapitalizationTable_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfCapitalizationTable_lbl" xml:lang="en-US">Schedule of Capitalization [Table]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfCapitalizationLineItems" xlink:label="us-gaap_ScheduleOfCapitalizationLineItems" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfCapitalizationLineItems" xlink:to="us-gaap_ScheduleOfCapitalizationLineItems_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfCapitalizationLineItems_lbl" xml:lang="en-US">Schedule of Capitalization [Line Items]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueNewIssues" xlink:label="us-gaap_StockIssuedDuringPeriodValueNewIssues" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockIssuedDuringPeriodValueNewIssues" xlink:to="us-gaap_StockIssuedDuringPeriodValueNewIssues_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockIssuedDuringPeriodValueNewIssues_lbl" xml:lang="en-US">Issuance of Common Stock</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SharePrice" xlink:label="us-gaap_SharePrice" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SharePrice" xlink:to="us-gaap_SharePrice_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="us-gaap_SharePrice_lbl" xml:lang="en-US">Public offering, price per share</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:label="us-gaap_StockIssuedDuringPeriodSharesNewIssues" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockIssuedDuringPeriodSharesNewIssues" xlink:to="us-gaap_StockIssuedDuringPeriodSharesNewIssues_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockIssuedDuringPeriodSharesNewIssues_lbl" xml:lang="en-US">Issuance of Common Stock in a public offering, shares</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CommonStockSharesAuthorized" xlink:to="us-gaap_CommonStockSharesAuthorized_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_CommonStockSharesAuthorized_2_lbl" xml:lang="en-US">Shares authorized</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_lbl" xml:lang="en-US">Authorized shares under plan</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_DividendReinvestmenPlanSharesIssuedCumulative" xlink:label="msex_DividendReinvestmenPlanSharesIssuedCumulative" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DividendReinvestmenPlanSharesIssuedCumulative" xlink:to="msex_DividendReinvestmenPlanSharesIssuedCumulative_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_DividendReinvestmenPlanSharesIssuedCumulative_lbl" xml:lang="en-US">Dividend Reinvestment &amp; Common Stock Purchase Plan, cumulative shares</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriod_lbl" xml:lang="en-US">Common stock granted and issued under plan</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockIssuedDuringPeriodValueDividendReinvestmentPlan" xlink:to="us-gaap_StockIssuedDuringPeriodValueDividendReinvestmentPlan_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_StockIssuedDuringPeriodValueDividendReinvestmentPlan_2_lbl" xml:lang="en-US">Issuance of shares under the DRP</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_AdditionalSharesAuthorizedBySECToBeIssued" xlink:label="msex_AdditionalSharesAuthorizedBySECToBeIssued" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_AdditionalSharesAuthorizedBySECToBeIssued" xlink:to="msex_AdditionalSharesAuthorizedBySECToBeIssued_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_AdditionalSharesAuthorizedBySECToBeIssued_lbl" xml:lang="en-US">Additional Shares Authorized By SEC To Be Issued</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_OtherLoanSourceMaximumBorrowingCapacity" xlink:label="msex_OtherLoanSourceMaximumBorrowingCapacity" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_OtherLoanSourceMaximumBorrowingCapacity" xlink:to="msex_OtherLoanSourceMaximumBorrowingCapacity_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_OtherLoanSourceMaximumBorrowingCapacity_lbl" xml:lang="en-US">Maximum borrowing amount</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_ConstructionLoanMaximumBorrowingCapacity" xlink:label="msex_ConstructionLoanMaximumBorrowingCapacity" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ConstructionLoanMaximumBorrowingCapacity" xlink:to="msex_ConstructionLoanMaximumBorrowingCapacity_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_ConstructionLoanMaximumBorrowingCapacity_lbl" xml:lang="en-US">Maximum borrowing capacity, construction loan</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_PercentageOfPrincipalWithStatedInterestRate" xlink:label="msex_PercentageOfPrincipalWithStatedInterestRate" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PercentageOfPrincipalWithStatedInterestRate" xlink:to="msex_PercentageOfPrincipalWithStatedInterestRate_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_PercentageOfPrincipalWithStatedInterestRate_lbl" xml:lang="en-US">Percentage of principal with stated interest rate</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_PercentageOfPrincipalWithMarketInterestRate" xlink:label="msex_PercentageOfPrincipalWithMarketInterestRate" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PercentageOfPrincipalWithMarketInterestRate" xlink:to="msex_PercentageOfPrincipalWithMarketInterestRate_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_PercentageOfPrincipalWithMarketInterestRate_lbl" xml:lang="en-US">Percentage of principal with market interest rate</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_PercentageOfPrincipalWithBondInterestRate" xlink:label="msex_PercentageOfPrincipalWithBondInterestRate" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PercentageOfPrincipalWithBondInterestRate" xlink:to="msex_PercentageOfPrincipalWithBondInterestRate_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_PercentageOfPrincipalWithBondInterestRate_lbl" xml:lang="en-US">Percentage of principal with bond interest rate</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_lbl" xml:lang="en-US">Maximum number of shares authorized for grant</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PreferredStockAmountOfPreferredDividendsInArrears" xlink:label="us-gaap_PreferredStockAmountOfPreferredDividendsInArrears" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PreferredStockAmountOfPreferredDividendsInArrears" xlink:to="us-gaap_PreferredStockAmountOfPreferredDividendsInArrears_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PreferredStockAmountOfPreferredDividendsInArrears_lbl" xml:lang="en-US">Preferred stock dividends in arrears</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockRepurchasedDuringPeriodShares" xlink:label="us-gaap_StockRepurchasedDuringPeriodShares" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockRepurchasedDuringPeriodShares" xlink:to="us-gaap_StockRepurchasedDuringPeriodShares_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockRepurchasedDuringPeriodShares_lbl" xml:lang="en-US">Shares repurchased in the period,shares</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockRepurchasedDuringPeriodValue" xlink:label="us-gaap_StockRepurchasedDuringPeriodValue" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockRepurchasedDuringPeriodValue" xlink:to="us-gaap_StockRepurchasedDuringPeriodValue_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockRepurchasedDuringPeriodValue_lbl" xml:lang="en-US">Shares repurchased in the period</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ConvertiblePreferredStockSharesIssuedUponConversion" xlink:label="us-gaap_ConvertiblePreferredStockSharesIssuedUponConversion" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ConvertiblePreferredStockSharesIssuedUponConversion" xlink:to="us-gaap_ConvertiblePreferredStockSharesIssuedUponConversion_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ConvertiblePreferredStockSharesIssuedUponConversion_lbl" xml:lang="en-US">Shares issued upon conversion</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ConversionOfStockSharesConverted1" xlink:label="us-gaap_ConversionOfStockSharesConverted1" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ConversionOfStockSharesConverted1" xlink:to="us-gaap_ConversionOfStockSharesConverted1_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ConversionOfStockSharesConverted1_lbl" xml:lang="en-US">Convertible preferred stock converted, shares</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities" xlink:label="us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities" xlink:to="us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockIssuedDuringPeriodValueConversionOfConvertibleSecurities_lbl" xml:lang="en-US">Convertible preferred stock converted, value</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" xlink:label="us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities" xlink:to="us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_StockIssuedDuringPeriodSharesConversionOfConvertibleSecurities_lbl" xml:lang="en-US">Stock issued upon conversion of convertible preferred stock (shares)</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DebtInstrumentFaceAmount" xlink:label="us-gaap_DebtInstrumentFaceAmount" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DebtInstrumentFaceAmount" xlink:to="us-gaap_DebtInstrumentFaceAmount_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DebtInstrumentFaceAmount_lbl" xml:lang="en-US">Loan amount</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ProceedsFromIssuanceOfLongTermDebt" xlink:to="us-gaap_ProceedsFromIssuanceOfLongTermDebt_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_ProceedsFromIssuanceOfLongTermDebt_2_lbl" xml:lang="en-US">Amount drawn</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LongTermDebt" xlink:to="us-gaap_LongTermDebt_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_LongTermDebt_2_lbl" xml:lang="en-US">Long-term debt</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_PercentageOfStockThatMayBeRedeemedInGivenCalanderYear" xlink:label="msex_PercentageOfStockThatMayBeRedeemedInGivenCalanderYear" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PercentageOfStockThatMayBeRedeemedInGivenCalanderYear" xlink:to="msex_PercentageOfStockThatMayBeRedeemedInGivenCalanderYear_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_PercentageOfStockThatMayBeRedeemedInGivenCalanderYear_lbl" xml:lang="en-US">Percentage of stock that may be redeemed in a given calander year</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_RepaymentsOfFirstMortgageBond" xlink:label="us-gaap_RepaymentsOfFirstMortgageBond" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RepaymentsOfFirstMortgageBond" xlink:to="us-gaap_RepaymentsOfFirstMortgageBond_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RepaymentsOfFirstMortgageBond_lbl" xml:lang="en-US">Repayment of first mortgage bonds</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ProceedsFromIssuanceOfFirstMortgageBond" xlink:label="us-gaap_ProceedsFromIssuanceOfFirstMortgageBond" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ProceedsFromIssuanceOfFirstMortgageBond" xlink:to="us-gaap_ProceedsFromIssuanceOfFirstMortgageBond_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ProceedsFromIssuanceOfFirstMortgageBond_lbl" xml:lang="en-US">Issuance of series bonds</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DebtInstrumentMaturityDate" xlink:to="us-gaap_DebtInstrumentMaturityDate_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_DebtInstrumentMaturityDate_2_lbl" xml:lang="en-US">Maturity date</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongtermDebtWeightedAverageInterestRate" xlink:label="us-gaap_LongtermDebtWeightedAverageInterestRate" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LongtermDebtWeightedAverageInterestRate" xlink:to="us-gaap_LongtermDebtWeightedAverageInterestRate_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LongtermDebtWeightedAverageInterestRate_lbl" xml:lang="en-US">Weighted average interest rate</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DeobligatedPrincipalPayments" xlink:to="msex_DeobligatedPrincipalPayments_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_DeobligatedPrincipalPayments_2_lbl" xml:lang="en-US">Deobligated principal payments</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherLongTermDebt" xlink:label="us-gaap_OtherLongTermDebt" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherLongTermDebt" xlink:to="us-gaap_OtherLongTermDebt_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OtherLongTermDebt_lbl" xml:lang="en-US">Other long term debt</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CustomerAdvancesForConstruction" xlink:to="us-gaap_CustomerAdvancesForConstruction_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_CustomerAdvancesForConstruction_2_lbl" xml:lang="en-US">Customer advances</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_LoanAmountInitiallySetUpAsMarketbasedVariableInterestRateTransaction" xlink:label="msex_LoanAmountInitiallySetUpAsMarketbasedVariableInterestRateTransaction" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_LoanAmountInitiallySetUpAsMarketbasedVariableInterestRateTransaction" xlink:to="msex_LoanAmountInitiallySetUpAsMarketbasedVariableInterestRateTransaction_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_LoanAmountInitiallySetUpAsMarketbasedVariableInterestRateTransaction_lbl" xml:lang="en-US">Loan amount initially set up as a market-based variable interest rate transaction</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths" xlink:label="us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths" xlink:to="us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInNextTwelveMonths_lbl" xml:lang="en-US">2018</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo" xlink:label="us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo" xlink:to="us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearTwo_lbl" xml:lang="en-US">2019</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree" xlink:label="us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree" xlink:to="us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearThree_lbl" xml:lang="en-US">2020</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour" xlink:label="us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour" xlink:to="us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFour_lbl" xml:lang="en-US">2021</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive" xlink:label="us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive" xlink:to="us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_LongTermDebtMaturitiesRepaymentsOfPrincipalInYearFive_lbl" xml:lang="en-US">2022</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EarningsPerShareBasicAbstract" xlink:label="us-gaap_EarningsPerShareBasicAbstract" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EarningsPerShareBasicAbstract" xlink:to="us-gaap_EarningsPerShareBasicAbstract_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_EarningsPerShareBasicAbstract_lbl" xml:lang="en-US">Basic:</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PreferredStockDividendsIncomeStatementImpact" xlink:to="us-gaap_PreferredStockDividendsIncomeStatementImpact_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_PreferredStockDividendsIncomeStatementImpact_2_lbl" xml:lang="en-US">Preferred Dividend</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic" xlink:to="us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NetIncomeLossAvailableToCommonStockholdersBasic_2_lbl" xml:lang="en-US">Earnings Applicable to Common Stock</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic" xlink:to="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_WeightedAverageNumberOfSharesOutstandingBasic_2_lbl" xml:lang="en-US">Weighted-average number of basic shares outstanding, shares</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EarningsPerShareBasic" xlink:to="us-gaap_EarningsPerShareBasic_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_EarningsPerShareBasic_2_lbl" xml:lang="en-US">Basic EPS</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_EarningsPerShareDilutedAbstract" xlink:label="us-gaap_EarningsPerShareDilutedAbstract" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EarningsPerShareDilutedAbstract" xlink:to="us-gaap_EarningsPerShareDilutedAbstract_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_EarningsPerShareDilutedAbstract_lbl" xml:lang="en-US">Diluted:</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_ConvertibleDollar7PreferredSeriesStockDividends" xlink:label="msex_ConvertibleDollar7PreferredSeriesStockDividends" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ConvertibleDollar7PreferredSeriesStockDividends" xlink:to="msex_ConvertibleDollar7PreferredSeriesStockDividends_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_ConvertibleDollar7PreferredSeriesStockDividends_lbl" xml:lang="en-US">$7.00 Series Preferred Dividend</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_ConvertibleDollar8PreferredSeriesStockDividends" xlink:label="msex_ConvertibleDollar8PreferredSeriesStockDividends" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ConvertibleDollar8PreferredSeriesStockDividends" xlink:to="msex_ConvertibleDollar8PreferredSeriesStockDividends_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_ConvertibleDollar8PreferredSeriesStockDividends_lbl" xml:lang="en-US">$8.00 Series Preferred Dividend</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted" xlink:label="us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted" xlink:to="us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NetIncomeLossAvailableToCommonStockholdersDiluted_lbl" xml:lang="en-US">Adjusted Earnings Applicable to Common Stock</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_IncrementalCommonSharesAttributableToConversionOfDollar7PreferredSeriesStock" xlink:label="msex_IncrementalCommonSharesAttributableToConversionOfDollar7PreferredSeriesStock" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_IncrementalCommonSharesAttributableToConversionOfDollar7PreferredSeriesStock" xlink:to="msex_IncrementalCommonSharesAttributableToConversionOfDollar7PreferredSeriesStock_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_IncrementalCommonSharesAttributableToConversionOfDollar7PreferredSeriesStock_lbl" xml:lang="en-US">Incremental common shares attributable to $7.00 series preferred shares, shares</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_IncrementalCommonSharesAttributableToConversionOfDollar8PreferredSeriesStock" xlink:label="msex_IncrementalCommonSharesAttributableToConversionOfDollar8PreferredSeriesStock" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_IncrementalCommonSharesAttributableToConversionOfDollar8PreferredSeriesStock" xlink:to="msex_IncrementalCommonSharesAttributableToConversionOfDollar8PreferredSeriesStock_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_IncrementalCommonSharesAttributableToConversionOfDollar8PreferredSeriesStock_lbl" xml:lang="en-US">Incremental common shares attributable to $8.00 series preferred shares, shares</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding" xlink:to="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_WeightedAverageNumberOfDilutedSharesOutstanding_2_lbl" xml:lang="en-US">Weighted-average diluted shares outstanding, shares</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EarningsPerShareDiluted" xlink:to="us-gaap_EarningsPerShareDiluted_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_EarningsPerShareDiluted_2_lbl" xml:lang="en-US">Diluted EPS</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_FirstMortgageBondsFairValueDisclosure" xlink:label="msex_FirstMortgageBondsFairValueDisclosure" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgageBondsFairValueDisclosure" xlink:to="msex_FirstMortgageBondsFairValueDisclosure_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_FirstMortgageBondsFairValueDisclosure_lbl" xml:lang="en-US">Bonds</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_StateRevolvingNotesFairValueDisclosure" xlink:label="msex_StateRevolvingNotesFairValueDisclosure" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_StateRevolvingNotesFairValueDisclosure" xlink:to="msex_StateRevolvingNotesFairValueDisclosure_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_StateRevolvingNotesFairValueDisclosure_lbl" xml:lang="en-US">State Revolving Notes</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation" xlink:label="us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation" xlink:to="us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DefinedBenefitPlanPensionPlansWithAccumulatedBenefitObligationsInExcessOfPlanAssetsAggregateAccumulatedBenefitObligation_lbl" xml:lang="en-US">Accumulated benefit obligation</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanHealthCareCostTrendRateAssumedNextFiscalYear" xlink:label="us-gaap_DefinedBenefitPlanHealthCareCostTrendRateAssumedNextFiscalYear" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanHealthCareCostTrendRateAssumedNextFiscalYear" xlink:to="us-gaap_DefinedBenefitPlanHealthCareCostTrendRateAssumedNextFiscalYear_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DefinedBenefitPlanHealthCareCostTrendRateAssumedNextFiscalYear_lbl" xml:lang="en-US">Increase (decrease) in annual rate per capita cost of covered healthcare benefits, next year</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_IncreaseDecreaseInAnnualRatePerCapitaCostOfCoveredHealthcareBenefitsYearsOneToThree" xlink:label="msex_IncreaseDecreaseInAnnualRatePerCapitaCostOfCoveredHealthcareBenefitsYearsOneToThree" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_IncreaseDecreaseInAnnualRatePerCapitaCostOfCoveredHealthcareBenefitsYearsOneToThree" xlink:to="msex_IncreaseDecreaseInAnnualRatePerCapitaCostOfCoveredHealthcareBenefitsYearsOneToThree_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_IncreaseDecreaseInAnnualRatePerCapitaCostOfCoveredHealthcareBenefitsYearsOneToThree_lbl" xml:lang="en-US">Increase (decrease) in annual rate per capita cost of covered healthcare benefits, 2019-2021</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_IncreaseDecreaseInAnnualRatePerCapitaCostOfCoveredHealthcareBenefitsYearsFourAndFive" xlink:label="msex_IncreaseDecreaseInAnnualRatePerCapitaCostOfCoveredHealthcareBenefitsYearsFourAndFive" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_IncreaseDecreaseInAnnualRatePerCapitaCostOfCoveredHealthcareBenefitsYearsFourAndFive" xlink:to="msex_IncreaseDecreaseInAnnualRatePerCapitaCostOfCoveredHealthcareBenefitsYearsFourAndFive_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_IncreaseDecreaseInAnnualRatePerCapitaCostOfCoveredHealthcareBenefitsYearsFourAndFive_lbl" xml:lang="en-US">Increase (decrease) in annual rate per capita cost of covered healthcare benefits, 2022-2023</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanUltimateHealthCareCostTrendRate1" xlink:label="us-gaap_DefinedBenefitPlanUltimateHealthCareCostTrendRate1" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanUltimateHealthCareCostTrendRate1" xlink:to="us-gaap_DefinedBenefitPlanUltimateHealthCareCostTrendRate1_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DefinedBenefitPlanUltimateHealthCareCostTrendRate1_lbl" xml:lang="en-US">Annual rate of increase in the per capita cost of covered healthcare benefits</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations" xlink:label="us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations" xlink:to="us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_DefinedBenefitPlanWeightedAverageAssetAllocations_lbl" xml:lang="en-US">Allocation of plan assets</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_CommonStockInPlanValue" xlink:label="msex_CommonStockInPlanValue" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_CommonStockInPlanValue" xlink:to="msex_CommonStockInPlanValue_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_CommonStockInPlanValue_lbl" xml:lang="en-US">Common stock in plan, value</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PensionAndOtherPostretirementBenefitContributions" xlink:label="us-gaap_PensionAndOtherPostretirementBenefitContributions" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PensionAndOtherPostretirementBenefitContributions" xlink:to="us-gaap_PensionAndOtherPostretirementBenefitContributions_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PensionAndOtherPostretirementBenefitContributions_lbl" xml:lang="en-US">Benfit plan, Cash contributions</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DescriptionOfDefinedContributionPensionAndOtherPostretirementPlans" xlink:label="us-gaap_DescriptionOfDefinedContributionPensionAndOtherPostretirementPlans" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DescriptionOfDefinedContributionPensionAndOtherPostretirementPlans" xlink:to="us-gaap_DescriptionOfDefinedContributionPensionAndOtherPostretirementPlans_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DescriptionOfDefinedContributionPensionAndOtherPostretirementPlans_lbl" xml:lang="en-US">Description of 401(k)</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_NumberOfHoursRequiredToParticipateInContributionPlan" xlink:label="msex_NumberOfHoursRequiredToParticipateInContributionPlan" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_NumberOfHoursRequiredToParticipateInContributionPlan" xlink:to="msex_NumberOfHoursRequiredToParticipateInContributionPlan_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_NumberOfHoursRequiredToParticipateInContributionPlan_lbl" xml:lang="en-US">Number of hours required to participate in contribution plan</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_PercentOfParticipantsContributionsMatchedByCompanyBelowOnePercentOfParticipantsCompensation" xlink:label="msex_PercentOfParticipantsContributionsMatchedByCompanyBelowOnePercentOfParticipantsCompensation" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PercentOfParticipantsContributionsMatchedByCompanyBelowOnePercentOfParticipantsCompensation" xlink:to="msex_PercentOfParticipantsContributionsMatchedByCompanyBelowOnePercentOfParticipantsCompensation_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_PercentOfParticipantsContributionsMatchedByCompanyBelowOnePercentOfParticipantsCompensation_lbl" xml:lang="en-US">Percent of participants contributions matched by company, below one percent of participants compensation</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_PercentOfParticipantsContributionsMatchedByCompanyAboveOnePercentOfParticipantsCompensation" xlink:label="msex_PercentOfParticipantsContributionsMatchedByCompanyAboveOnePercentOfParticipantsCompensation" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PercentOfParticipantsContributionsMatchedByCompanyAboveOnePercentOfParticipantsCompensation" xlink:to="msex_PercentOfParticipantsContributionsMatchedByCompanyAboveOnePercentOfParticipantsCompensation_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_PercentOfParticipantsContributionsMatchedByCompanyAboveOnePercentOfParticipantsCompensation_lbl" xml:lang="en-US">Percent of participants contributions matched by company, above one percent of participants compensation</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_ThresholdPercentageOfParticipantsCompensationAtWhichMatchingDecreases" xlink:label="msex_ThresholdPercentageOfParticipantsCompensationAtWhichMatchingDecreases" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ThresholdPercentageOfParticipantsCompensationAtWhichMatchingDecreases" xlink:to="msex_ThresholdPercentageOfParticipantsCompensationAtWhichMatchingDecreases_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_ThresholdPercentageOfParticipantsCompensationAtWhichMatchingDecreases_lbl" xml:lang="en-US">Threshold percentage of participants compensation at which matching decreases</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent" xlink:label="us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent" xlink:to="us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DefinedContributionPlanEmployerMatchingContributionPercent_lbl" xml:lang="en-US">Matching contributions, percent</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_MatchingContributions" xlink:label="msex_MatchingContributions" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_MatchingContributions" xlink:to="msex_MatchingContributions_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_MatchingContributions_lbl" xml:lang="en-US">Matching contributions</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_DefinedContributionPlanEmployerDiscretionaryContributionPercent" xlink:label="msex_DefinedContributionPlanEmployerDiscretionaryContributionPercent" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DefinedContributionPlanEmployerDiscretionaryContributionPercent" xlink:to="msex_DefinedContributionPlanEmployerDiscretionaryContributionPercent_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_DefinedContributionPlanEmployerDiscretionaryContributionPercent_lbl" xml:lang="en-US">Discretionary contributions, percent</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedContributionPlanEmployerDiscretionaryContributionAmount" xlink:label="us-gaap_DefinedContributionPlanEmployerDiscretionaryContributionAmount" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedContributionPlanEmployerDiscretionaryContributionAmount" xlink:to="us-gaap_DefinedContributionPlanEmployerDiscretionaryContributionAmount_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DefinedContributionPlanEmployerDiscretionaryContributionAmount_lbl" xml:lang="en-US">Discretionary contributions</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_EscrowAccountMaintainedFor2008RestrictedStockPlan" xlink:label="msex_EscrowAccountMaintainedFor2008RestrictedStockPlan" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_EscrowAccountMaintainedFor2008RestrictedStockPlan" xlink:to="msex_EscrowAccountMaintainedFor2008RestrictedStockPlan_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_EscrowAccountMaintainedFor2008RestrictedStockPlan_lbl" xml:lang="en-US">Escrow account maintained for 2008 restricted stock plan</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_2_lbl" xml:lang="en-US">Maximum number of shares authorized for grant</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAvailableForGrant_2_lbl" xml:lang="en-US">Number of shares authorized for grant, unissued</link:label>
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      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsVestedInPeriodTotalFairValue_lbl" xml:lang="en-US">Fair value of vested restricted shares</link:label>
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      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DecreaseInPensionAndOtherPostretirementDefinedBenefitPlansLiabilities" xlink:to="msex_DecreaseInPensionAndOtherPostretirementDefinedBenefitPlansLiabilities_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_DecreaseInPensionAndOtherPostretirementDefinedBenefitPlansLiabilities_lbl" xml:lang="en-US">Decrease in employee benefit plans liability and related regulatory asset</link:label>
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      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ChangeInProjectedBenefitObligationAbstract" xlink:to="msex_ChangeInProjectedBenefitObligationAbstract_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_ChangeInProjectedBenefitObligationAbstract_lbl" xml:lang="en-US">Change in Projected Benefit Obligation:</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanBenefitObligation" xlink:label="us-gaap_DefinedBenefitPlanBenefitObligation" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanBenefitObligation" xlink:to="us-gaap_DefinedBenefitPlanBenefitObligation_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="us-gaap_DefinedBenefitPlanBenefitObligation_lbl" xml:lang="en-US">Beginning Balance</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanPlanAmendments" xlink:label="us-gaap_DefinedBenefitPlanPlanAmendments" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanPlanAmendments" xlink:to="us-gaap_DefinedBenefitPlanPlanAmendments_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DefinedBenefitPlanPlanAmendments_lbl" xml:lang="en-US">Plan Amendment</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanServiceCost" xlink:label="us-gaap_DefinedBenefitPlanServiceCost" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanServiceCost" xlink:to="us-gaap_DefinedBenefitPlanServiceCost_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DefinedBenefitPlanServiceCost_lbl" xml:lang="en-US">Service Cost</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanInterestCost" xlink:label="us-gaap_DefinedBenefitPlanInterestCost" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanInterestCost" xlink:to="us-gaap_DefinedBenefitPlanInterestCost_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DefinedBenefitPlanInterestCost_lbl" xml:lang="en-US">Interest Cost</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanActuarialGainLoss" xlink:label="us-gaap_DefinedBenefitPlanActuarialGainLoss" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanActuarialGainLoss" xlink:to="us-gaap_DefinedBenefitPlanActuarialGainLoss_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_DefinedBenefitPlanActuarialGainLoss_lbl" xml:lang="en-US">Actuarial Loss</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanPlanAssetsBenefitsPaid" xlink:label="us-gaap_DefinedBenefitPlanPlanAssetsBenefitsPaid" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanPlanAssetsBenefitsPaid" xlink:to="us-gaap_DefinedBenefitPlanPlanAssetsBenefitsPaid_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_DefinedBenefitPlanPlanAssetsBenefitsPaid_lbl" xml:lang="en-US">Benefits Paid</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanBenefitObligation" xlink:to="us-gaap_DefinedBenefitPlanBenefitObligation_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="us-gaap_DefinedBenefitPlanBenefitObligation_2_lbl" xml:lang="en-US">Ending Balance</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_ChangeInFairValueOfPlanAssetsAbstract" xlink:label="msex_ChangeInFairValueOfPlanAssetsAbstract" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ChangeInFairValueOfPlanAssetsAbstract" xlink:to="msex_ChangeInFairValueOfPlanAssetsAbstract_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_ChangeInFairValueOfPlanAssetsAbstract_lbl" xml:lang="en-US">Change in Fair Value of Plan Assets:</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanFairValueOfPlanAssets" xlink:label="us-gaap_DefinedBenefitPlanFairValueOfPlanAssets" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanFairValueOfPlanAssets" xlink:to="us-gaap_DefinedBenefitPlanFairValueOfPlanAssets_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="us-gaap_DefinedBenefitPlanFairValueOfPlanAssets_lbl" xml:lang="en-US">Beginning Balance</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets" xlink:label="us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets" xlink:to="us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DefinedBenefitPlanActualReturnOnPlanAssets_lbl" xml:lang="en-US">Actual Return on Plan Assets</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanContributionsByEmployer" xlink:label="us-gaap_DefinedBenefitPlanContributionsByEmployer" />
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      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DefinedBenefitPlanContributionsByEmployer_lbl" xml:lang="en-US">Employer Contributions</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanFairValueOfPlanAssets" xlink:to="us-gaap_DefinedBenefitPlanFairValueOfPlanAssets_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="us-gaap_DefinedBenefitPlanFairValueOfPlanAssets_2_lbl" xml:lang="en-US">Ending Balance</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanFundedStatusOfPlan" xlink:label="us-gaap_DefinedBenefitPlanFundedStatusOfPlan" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanFundedStatusOfPlan" xlink:to="us-gaap_DefinedBenefitPlanFundedStatusOfPlan_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="us-gaap_DefinedBenefitPlanFundedStatusOfPlan_lbl" xml:lang="en-US">Funded Status</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities" xlink:label="us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities" xlink:to="us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansCurrentLiabilities_lbl" xml:lang="en-US">Current Liability</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent" xlink:to="us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesNoncurrent_2_lbl" xml:lang="en-US">Noncurrent Liability</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesCurrentAndNoncurrent" xlink:label="us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesCurrentAndNoncurrent" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesCurrentAndNoncurrent" xlink:to="us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesCurrentAndNoncurrent_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PensionAndOtherPostretirementDefinedBenefitPlansLiabilitiesCurrentAndNoncurrent_lbl" xml:lang="en-US">Net Liability Recognized</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanNetPeriodicBenefitCostAbstract" xlink:label="us-gaap_DefinedBenefitPlanNetPeriodicBenefitCostAbstract" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanNetPeriodicBenefitCostAbstract" xlink:to="us-gaap_DefinedBenefitPlanNetPeriodicBenefitCostAbstract_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DefinedBenefitPlanNetPeriodicBenefitCostAbstract_lbl" xml:lang="en-US">Periodic costs for employee retirement benefit plans</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets" xlink:label="us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets" xlink:to="us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_DefinedBenefitPlanExpectedReturnOnPlanAssets_lbl" xml:lang="en-US">Expected Return on Plan Assets</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanAmortizationOfTransitionAssetObligation" xlink:label="us-gaap_DefinedBenefitPlanAmortizationOfTransitionAssetObligation" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanAmortizationOfTransitionAssetObligation" xlink:to="us-gaap_DefinedBenefitPlanAmortizationOfTransitionAssetObligation_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DefinedBenefitPlanAmortizationOfTransitionAssetObligation_lbl" xml:lang="en-US">Amortization of Net Transition Obligation</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses" xlink:label="us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses" />
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      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_DefinedBenefitPlanAmortizationOfGainsLosses_lbl" xml:lang="en-US">Amortization of Net Actuarial Loss</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit" xlink:label="us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit" />
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      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DefinedBenefitPlanAmortizationOfPriorServiceCostCredit_lbl" xml:lang="en-US">Amortization of Prior Service Credit</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost" xlink:label="us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost" xlink:to="us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:label="us-gaap_DefinedBenefitPlanNetPeriodicBenefitCost_lbl" xml:lang="en-US">Net Periodic Benefit Cost</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_ExpectedAmortizedActuarialLoss" xlink:label="msex_ExpectedAmortizedActuarialLoss" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ExpectedAmortizedActuarialLoss" xlink:to="msex_ExpectedAmortizedActuarialLoss_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_ExpectedAmortizedActuarialLoss_lbl" xml:lang="en-US">Actuarial Loss</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_ExpectedAmortizedPriorServiceCredit" xlink:label="msex_ExpectedAmortizedPriorServiceCredit" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ExpectedAmortizedPriorServiceCredit" xlink:to="msex_ExpectedAmortizedPriorServiceCredit_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_ExpectedAmortizedPriorServiceCredit_lbl" xml:lang="en-US">Prior Service Credit</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_WeightedAverageAssumptionsAbstract" xlink:label="msex_WeightedAverageAssumptionsAbstract" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_WeightedAverageAssumptionsAbstract" xlink:to="msex_WeightedAverageAssumptionsAbstract_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_WeightedAverageAssumptionsAbstract_lbl" xml:lang="en-US">Weighted Average Assumptions:</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets" xlink:label="us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets" xlink:to="us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostExpectedLongTermReturnOnAssets_lbl" xml:lang="en-US">Expected Return on Plan Assets</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_DiscountRateForAbstract" xlink:label="msex_DiscountRateForAbstract" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DiscountRateForAbstract" xlink:to="msex_DiscountRateForAbstract_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_DiscountRateForAbstract_lbl" xml:lang="en-US">Discount Rate for:</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate" xlink:label="us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate" />
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      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationDiscountRate_lbl" xml:lang="en-US">Benefit Obligation</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate" xlink:label="us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate" xlink:to="us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostDiscountRate_lbl" xml:lang="en-US">Benefit Cost</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_CompensationIncreaseForAbstract" xlink:label="msex_CompensationIncreaseForAbstract" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_CompensationIncreaseForAbstract" xlink:to="msex_CompensationIncreaseForAbstract_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_CompensationIncreaseForAbstract_lbl" xml:lang="en-US">Compensation Increase for:</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease" xlink:label="us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease" xlink:to="us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingBenefitObligationRateOfCompensationIncrease_lbl" xml:lang="en-US">Benefit Obligation</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease" xlink:label="us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease" xlink:to="us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_DefinedBenefitPlanAssumptionsUsedCalculatingNetPeriodicBenefitCostRateOfCompensationIncrease_lbl" xml:lang="en-US">Benefit Cost</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnServiceAndInterestCostComponents" xlink:label="us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnServiceAndInterestCostComponents" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnServiceAndInterestCostComponents" xlink:to="us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnServiceAndInterestCostComponents_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnServiceAndInterestCostComponents_lbl" xml:lang="en-US">Effect on Current Year's Service and Interest Cost - Increase</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnAccumulatedPostretirementBenefitObligation" xlink:label="us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnAccumulatedPostretirementBenefitObligation" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnAccumulatedPostretirementBenefitObligation" xlink:to="us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnAccumulatedPostretirementBenefitObligation_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointIncreaseOnAccumulatedPostretirementBenefitObligation_lbl" xml:lang="en-US">Effect on Projected Benefit Obligation - Increase</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnServiceAndInterestCostComponents1" xlink:label="us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnServiceAndInterestCostComponents1" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnServiceAndInterestCostComponents1" xlink:to="us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnServiceAndInterestCostComponents1_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnServiceAndInterestCostComponents1_lbl" xml:lang="en-US">Effect on Current Year's Service and Interest Cost - Decrease</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnAccumulatedPostretirementBenefitObligation1" xlink:label="us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnAccumulatedPostretirementBenefitObligation1" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnAccumulatedPostretirementBenefitObligation1" xlink:to="us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnAccumulatedPostretirementBenefitObligation1_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_DefinedBenefitPlanEffectOfOnePercentagePointDecreaseOnAccumulatedPostretirementBenefitObligation1_lbl" xml:lang="en-US">Effect on Projected Benefit Obligation - Decrease</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths" xlink:label="us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths" xlink:to="us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsNextTwelveMonths_lbl" xml:lang="en-US">2018</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo" xlink:label="us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo" xlink:to="us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearTwo_lbl" xml:lang="en-US">2019</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree" xlink:label="us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree" xlink:to="us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearThree_lbl" xml:lang="en-US">2020</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour" xlink:label="us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour" xlink:to="us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFour_lbl" xml:lang="en-US">2021</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive" xlink:label="us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive" xlink:to="us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsYearFive_lbl" xml:lang="en-US">2022</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter" xlink:label="us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter" xlink:to="us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DefinedBenefitPlanExpectedFutureBenefitPaymentsFiveFiscalYearsThereafter_lbl" xml:lang="en-US">2023-2027</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_BenefitPaymentsTotals" xlink:label="msex_BenefitPaymentsTotals" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_BenefitPaymentsTotals" xlink:to="msex_BenefitPaymentsTotals_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_BenefitPaymentsTotals_lbl" xml:lang="en-US">Totals</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_DefinedBenefitPlanPlanAssetsTargetAllocationPercentage" xlink:label="us-gaap_DefinedBenefitPlanPlanAssetsTargetAllocationPercentage" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanPlanAssetsTargetAllocationPercentage" xlink:to="us-gaap_DefinedBenefitPlanPlanAssetsTargetAllocationPercentage_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_DefinedBenefitPlanPlanAssetsTargetAllocationPercentage_lbl" xml:lang="en-US">Target plan allocations</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_DefinedBenefitPlanFairValueOfPlanAssets" xlink:to="us-gaap_DefinedBenefitPlanFairValueOfPlanAssets_3_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_DefinedBenefitPlanFairValueOfPlanAssets_3_lbl" xml:lang="en-US">Fair value of plan assets</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingRollForward" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingRollForward" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingRollForward" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingRollForward_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingRollForward_lbl" xml:lang="en-US">Shares</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber_lbl" xml:lang="en-US">Balance</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsGranted" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsGranted" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsGranted" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsGranted_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsGranted_lbl" xml:lang="en-US">Granted</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExercised" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExercised" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExercised" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExercised_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsExercised_lbl" xml:lang="en-US">Vested</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsForfeitures" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsForfeitures" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsForfeitures" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsForfeitures_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2009/role/negatedLabel" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsForfeitures_lbl" xml:lang="en-US">Forfeited</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOther" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOther" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOther" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOther_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOther_lbl" xml:lang="en-US">Amortization of Compensation Expense</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNonOptionEquityInstrumentsOutstandingNumber_2_lbl" xml:lang="en-US">Balance</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_UnearnedCompensationAbstract" xlink:label="msex_UnearnedCompensationAbstract" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_UnearnedCompensationAbstract" xlink:to="msex_UnearnedCompensationAbstract_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_UnearnedCompensationAbstract_lbl" xml:lang="en-US">Unearned compensation</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_ShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsWeightedAverageGrantDateValueUnearnedCompensation" xlink:label="msex_ShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsWeightedAverageGrantDateValueUnearnedCompensation" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsWeightedAverageGrantDateValueUnearnedCompensation" xlink:to="msex_ShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsWeightedAverageGrantDateValueUnearnedCompensation_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodStartLabel" xlink:label="msex_ShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsWeightedAverageGrantDateValueUnearnedCompensation_lbl" xml:lang="en-US">Balance</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_GrantedUnearnedCompensation" xlink:label="msex_GrantedUnearnedCompensation" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_GrantedUnearnedCompensation" xlink:to="msex_GrantedUnearnedCompensation_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_GrantedUnearnedCompensation_lbl" xml:lang="en-US">Granted</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_VestedUnearnedCompensation" xlink:label="msex_VestedUnearnedCompensation" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_VestedUnearnedCompensation" xlink:to="msex_VestedUnearnedCompensation_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_VestedUnearnedCompensation_lbl" xml:lang="en-US">Vested</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_ForfeitedUnearnedCompensation" xlink:label="msex_ForfeitedUnearnedCompensation" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ForfeitedUnearnedCompensation" xlink:to="msex_ForfeitedUnearnedCompensation_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_ForfeitedUnearnedCompensation_lbl" xml:lang="en-US">Forfeited</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_AmortizationOfCompensationExpenseUnearnedCompensation" xlink:label="msex_AmortizationOfCompensationExpenseUnearnedCompensation" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_AmortizationOfCompensationExpenseUnearnedCompensation" xlink:to="msex_AmortizationOfCompensationExpenseUnearnedCompensation_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="msex_AmortizationOfCompensationExpenseUnearnedCompensation_lbl" xml:lang="en-US">Amortization of Compensation Expense</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsWeightedAverageGrantDateValueUnearnedCompensation" xlink:to="msex_ShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsWeightedAverageGrantDateValueUnearnedCompensation_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/periodEndLabel" xlink:label="msex_ShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsWeightedAverageGrantDateValueUnearnedCompensation_2_lbl" xml:lang="en-US">Balance</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsNonvestedWeightedAverageGrantDateFairValueRollForward_lbl" xml:lang="en-US">Weighted Average Grant Price</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue" xlink:to="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantsInPeriodWeightedAverageGrantDateFairValue_lbl" xml:lang="en-US">Granted</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable" xlink:to="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_ScheduleOfSegmentReportingInformationBySegmentTable_lbl" xml:lang="en-US">Schedule of Segment Reporting Information, by Segment [Table]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_SegmentReportingInformationLineItems" xlink:label="us-gaap_SegmentReportingInformationLineItems" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_SegmentReportingInformationLineItems" xlink:to="us-gaap_SegmentReportingInformationLineItems_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_SegmentReportingInformationLineItems_lbl" xml:lang="en-US">Segment Reporting Information [Line Items]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_StatementBusinessSegmentsAxis" xlink:to="us-gaap_StatementBusinessSegmentsAxis_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_StatementBusinessSegmentsAxis_2_lbl" xml:lang="en-US">Segments [Axis]</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_NumberOfReportableSegments" xlink:label="us-gaap_NumberOfReportableSegments" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NumberOfReportableSegments" xlink:to="us-gaap_NumberOfReportableSegments_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NumberOfReportableSegments_lbl" xml:lang="en-US">Number of Reportable Segments</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_RegulatedAndUnregulatedOperatingRevenue" xlink:to="us-gaap_RegulatedAndUnregulatedOperatingRevenue_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_RegulatedAndUnregulatedOperatingRevenue_2_lbl" xml:lang="en-US">Revenues</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OperatingIncomeLoss" xlink:to="us-gaap_OperatingIncomeLoss_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OperatingIncomeLoss_2_lbl" xml:lang="en-US">Operating Income</link:label>
      <link:loc xlink:type="locator" xlink:href="http://xbrl.fasb.org/us-gaap/2017/elts/us-gaap-2017-01-31.xsd#us-gaap_OtherNonrecurringIncomeExpense" xlink:label="us-gaap_OtherNonrecurringIncomeExpense" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherNonrecurringIncomeExpense" xlink:to="us-gaap_OtherNonrecurringIncomeExpense_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OtherNonrecurringIncomeExpense_lbl" xml:lang="en-US">Other Income (Expense), Net</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_InterestExpense" xlink:to="us-gaap_InterestExpense_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:label="us-gaap_InterestExpense_2_lbl" xml:lang="en-US">Interest Expense</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PaymentsToAcquireWaterAndWasteWaterSystems" xlink:to="us-gaap_PaymentsToAcquireWaterAndWasteWaterSystems_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PaymentsToAcquireWaterAndWasteWaterSystems_2_lbl" xml:lang="en-US">Capital Expenditures</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_Assets" xlink:to="us-gaap_Assets_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_Assets_2_lbl" xml:lang="en-US">Assets</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EarningsPerShareBasic" xlink:to="us-gaap_EarningsPerShareBasic_3_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_EarningsPerShareBasic_3_lbl" xml:lang="en-US">Basic Earnings per Share</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_EarningsPerShareDiluted" xlink:to="us-gaap_EarningsPerShareDiluted_3_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:label="us-gaap_EarningsPerShareDiluted_3_lbl" xml:lang="en-US">Diluted Earnings per Share</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_AcquisitionPremiums" xlink:to="msex_AcquisitionPremiums_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_AcquisitionPremiums_doc" xml:lang="en-US">Acquisition premiums</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_AdditionalSharesAuthorizedBySECToBeIssued" xlink:to="msex_AdditionalSharesAuthorizedBySECToBeIssued_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_AdditionalSharesAuthorizedBySECToBeIssued_doc" xml:lang="en-US">Additional common shares authorized by the SEC for issuance under the investment plan.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_AllLongTermDebtMember" xlink:to="msex_AllLongTermDebtMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_AllLongTermDebtMember_doc" xml:lang="en-US">All Long-term Debt [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_AllocationOfPlanAssetsTableTextBlock" xlink:to="msex_AllocationOfPlanAssetsTableTextBlock_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_AllocationOfPlanAssetsTableTextBlock_doc" xml:lang="en-US">Allocation of plan assets</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_AllowanceForFundsUsedDuringConstructionRatesTableTextBlock" xlink:to="msex_AllowanceForFundsUsedDuringConstructionRatesTableTextBlock_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_AllowanceForFundsUsedDuringConstructionRatesTableTextBlock_doc" xml:lang="en-US">Allowance for Funds Used During Construction Rates</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_AmortizationOfCompensationExpenseUnearnedCompensation" xlink:to="msex_AmortizationOfCompensationExpenseUnearnedCompensation_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_AmortizationOfCompensationExpenseUnearnedCompensation_doc" xml:lang="en-US">Amortization of Compensation Expense - Unearned compensation</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_AmountsExpectedToBeAmortizedFromRegulatoryAssetsTableTextBlock" xlink:to="msex_AmountsExpectedToBeAmortizedFromRegulatoryAssetsTableTextBlock_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_AmountsExpectedToBeAmortizedFromRegulatoryAssetsTableTextBlock_doc" xml:lang="en-US">Amounts expected to be amortized from regulatory assets</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_BaseRateAmount" xlink:to="msex_BaseRateAmount_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_BaseRateAmount_doc" xml:lang="en-US">The base amount used for water rates.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_BaseRateIncrease" xlink:to="msex_BaseRateIncrease_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_BaseRateIncrease_doc" xml:lang="en-US">Increase in base rates revenue per year</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_BenefitPaymentsTotals" xlink:to="msex_BenefitPaymentsTotals_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_BenefitPaymentsTotals_doc" xml:lang="en-US">Total amount of benefit payments.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_BudgetedConstructionCost" xlink:to="msex_BudgetedConstructionCost_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_BudgetedConstructionCost_doc" xml:lang="en-US">Budgeted construction cost for construction program, next year</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_BudgetedConstructionCostForConstructionProgramYearOne" xlink:to="msex_BudgetedConstructionCostForConstructionProgramYearOne_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_BudgetedConstructionCostForConstructionProgramYearOne_doc" xml:lang="en-US">Budgeted construction cost for construction program, year one.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_BudgetedConstructionCostForConstructionProgramYearTwo" xlink:to="msex_BudgetedConstructionCostForConstructionProgramYearTwo_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_BudgetedConstructionCostForConstructionProgramYearTwo_doc" xml:lang="en-US">Budgeted construction cost for construction program, year two</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_CapitalizationTextBlock" xlink:to="msex_CapitalizationTextBlock_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_CapitalizationTextBlock_doc" xml:lang="en-US">The entire disclosure for Capitalization.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_CashPaidDuringYearForAbstract" xlink:to="msex_CashPaidDuringYearForAbstract_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_CashPaidDuringYearForAbstract_doc" xml:lang="en-US">Cash Paid During the Year for:</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ChangeInFairValueOfPlanAssetsAbstract" xlink:to="msex_ChangeInFairValueOfPlanAssetsAbstract_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_ChangeInFairValueOfPlanAssetsAbstract_doc" xml:lang="en-US">Change in Fair Value of Plan Assets:</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ChangeInProjectedBenefitObligationAbstract" xlink:to="msex_ChangeInProjectedBenefitObligationAbstract_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_ChangeInProjectedBenefitObligationAbstract_doc" xml:lang="en-US">Change in Projected Benefit Obligation:</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_CommitmentAndContingenciesLineItems" xlink:to="msex_CommitmentAndContingenciesLineItems_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_CommitmentAndContingenciesLineItems_doc" xml:lang="en-US">Commitment And Contingencies [Line Items].</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_CommitmentAndContingenciesTable" xlink:to="msex_CommitmentAndContingenciesTable_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_CommitmentAndContingenciesTable_doc" xml:lang="en-US">Commitment And Contingencies [Table].</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_CommonStockInPlanValue" xlink:to="msex_CommonStockInPlanValue_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_CommonStockInPlanValue_doc" xml:lang="en-US">The value of equity securities with the plan.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_CompensationIncreaseForAbstract" xlink:to="msex_CompensationIncreaseForAbstract_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_CompensationIncreaseForAbstract_doc" xml:lang="en-US">Compensation Increase for:</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ConstructionLoanMaximumBorrowingCapacity" xlink:to="msex_ConstructionLoanMaximumBorrowingCapacity_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_ConstructionLoanMaximumBorrowingCapacity_doc" xml:lang="en-US">The maximum borrowing capacity for the construction loan as outlined in the closed agreement. Borrowings will take place when construction on a qualifying project is substantially complete.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ConstructionLoanMember" xlink:to="msex_ConstructionLoanMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_ConstructionLoanMember_doc" xml:lang="en-US">Construction Loan [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ConvertibleDollar7PreferredSeriesStockDividends" xlink:to="msex_ConvertibleDollar7PreferredSeriesStockDividends_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_ConvertibleDollar7PreferredSeriesStockDividends_doc" xml:lang="en-US">Amount of paid and unpaid cash, stock, and paid-in-kind (PIK) dividends declared convertible $7.00 preferred stock.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ConvertibleDollar8PreferredSeriesStockDividends" xlink:to="msex_ConvertibleDollar8PreferredSeriesStockDividends_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_ConvertibleDollar8PreferredSeriesStockDividends_doc" xml:lang="en-US">Amount of paid and unpaid cash, stock, and paid-in-kind (PIK) dividends declared convertible $8.00 preferred stock.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ConvertiblePreferredStock1Member" xlink:to="msex_ConvertiblePreferredStock1Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_ConvertiblePreferredStock1Member_doc" xml:lang="en-US">Refers to series of convertible prederred stock.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ConvertiblePreferredStockSeries7Member" xlink:to="msex_ConvertiblePreferredStockSeries7Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_ConvertiblePreferredStockSeries7Member_doc" xml:lang="en-US">Convertible Preferred Stock $7.00 Series</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ConvertiblePreferredStockSeries8Member" xlink:to="msex_ConvertiblePreferredStockSeries8Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_ConvertiblePreferredStockSeries8Member_doc" xml:lang="en-US">Convertible Preferred Stock $8.00 Series</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_CostOfPurchasedWaterAbstract" xlink:to="msex_CostOfPurchasedWaterAbstract_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_CostOfPurchasedWaterAbstract_doc" xml:lang="en-US">Purchased Water</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_CostOfTreatedWater" xlink:to="msex_CostOfTreatedWater_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_CostOfTreatedWater_doc" xml:lang="en-US">Refers to cost of treated water during the period.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_CostOfUntreatedWater" xlink:to="msex_CostOfUntreatedWater_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_CostOfUntreatedWater_doc" xml:lang="en-US">Refers to cost of untreated water during the period.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_CurrentAbstract" xlink:to="msex_CurrentAbstract_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_CurrentAbstract_doc" xml:lang="en-US">Current:</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_CustomersAdvancesForConstructionCacPolicyTextBlock" xlink:to="msex_CustomersAdvancesForConstructionCacPolicyTextBlock_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_CustomersAdvancesForConstructionCacPolicyTextBlock_doc" xml:lang="en-US">Disclosure of accounting policy for customer advances for construction.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DecreaseInPensionAndOtherPostretirementDefinedBenefitPlansLiabilities" xlink:to="msex_DecreaseInPensionAndOtherPostretirementDefinedBenefitPlansLiabilities_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_DecreaseInPensionAndOtherPostretirementDefinedBenefitPlansLiabilities_doc" xml:lang="en-US">Refers to decrease in pension and other postretirement defined benefit plans liabilities.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DeferredAbstract" xlink:to="msex_DeferredAbstract_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_DeferredAbstract_doc" xml:lang="en-US">Deferred:</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DeferredChargesAndOtherAssets" xlink:to="msex_DeferredChargesAndOtherAssets_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_DeferredChargesAndOtherAssets_doc" xml:lang="en-US">This element represents aggregate carrying amount, at the balance sheet date, of noncurrent deferred charges held by public utility entities and other noncurrent assets not separately disclosed in the balance sheet.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DeferredChargesAndOtherAssetsAbstract" xlink:to="msex_DeferredChargesAndOtherAssetsAbstract_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_DeferredChargesAndOtherAssetsAbstract_doc" xml:lang="en-US">Deferred Charges And Other Assets [Abstract].</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DeferredTaxAssetsCustomerAdvances" xlink:to="msex_DeferredTaxAssetsCustomerAdvances_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_DeferredTaxAssetsCustomerAdvances_doc" xml:lang="en-US">Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences derived customer advances.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DeferredTaxLiabilitiesInvestmentTaxCredits" xlink:to="msex_DeferredTaxLiabilitiesInvestmentTaxCredits_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_DeferredTaxLiabilitiesInvestmentTaxCredits_doc" xml:lang="en-US">Amount before allocation of valuation allowances of deferred tax liabilities attributable to deductible investment tax credits.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DeferredTaxLiabilitiesUtilityPlantRelated" xlink:to="msex_DeferredTaxLiabilitiesUtilityPlantRelated_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_DeferredTaxLiabilitiesUtilityPlantRelated_doc" xml:lang="en-US">Amount of deferred tax liability attributable to taxable temporary differences of utility plant related.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DefinedContributionPlanEmployerDiscretionaryContributionPercent" xlink:to="msex_DefinedContributionPlanEmployerDiscretionaryContributionPercent_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_DefinedContributionPlanEmployerDiscretionaryContributionPercent_doc" xml:lang="en-US">Percentage employer discretionary contribution to a defined contribution plan.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DelawarePublicServiceCommissionMember" xlink:to="msex_DelawarePublicServiceCommissionMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_DelawarePublicServiceCommissionMember_doc" xml:lang="en-US">Delaware Public Service Commission [Member].</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DelawareStateRevolvingFundMember" xlink:to="msex_DelawareStateRevolvingFundMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_DelawareStateRevolvingFundMember_doc" xml:lang="en-US">Delaware State Revolving Fund.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DeobligatedPrincipalPayments" xlink:to="msex_DeobligatedPrincipalPayments_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_DeobligatedPrincipalPayments_doc" xml:lang="en-US">Refers to value of long term debt deobligation in noncash investing and financing activities.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DiscountRateForAbstract" xlink:to="msex_DiscountRateForAbstract_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_DiscountRateForAbstract_doc" xml:lang="en-US">Discount Rate for:</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DistributionsFromInvestmentInJointVenture" xlink:to="msex_DistributionsFromInvestmentInJointVenture_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_DistributionsFromInvestmentInJointVenture_doc" xml:lang="en-US">The cash inflow from or outflow to company joint ventures.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DividendReinvestmenPlanSharesIssuedCumulative" xlink:to="msex_DividendReinvestmenPlanSharesIssuedCumulative_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_DividendReinvestmenPlanSharesIssuedCumulative_doc" xml:lang="en-US">Total cumulative shares issued under dividend reinvestment plan.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DividendReinvestmentCommonStockPurchasePlanMember" xlink:to="msex_DividendReinvestmentCommonStockPurchasePlanMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_DividendReinvestmentCommonStockPurchasePlanMember_doc" xml:lang="en-US">Dividend Reinvestment and Common Stock Purchase Plan</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DocumentAndEntityInformationAbstract" xlink:to="msex_DocumentAndEntityInformationAbstract_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_DocumentAndEntityInformationAbstract_doc" xml:lang="en-US">Document And Entity Information [Abstract].</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DsicRateIncrease" xlink:to="msex_DsicRateIncrease_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_DsicRateIncrease_doc" xml:lang="en-US">The amount of a distribution system improvement charge rate increase.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_EmployeeBenefits" xlink:to="msex_EmployeeBenefits_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_EmployeeBenefits_doc" xml:lang="en-US">Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to nondeductible employee benefit costs.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_EntityClosingMarketPricePerShare" xlink:to="msex_EntityClosingMarketPricePerShare_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_EntityClosingMarketPricePerShare_doc" xml:lang="en-US">Entity Closing Market Price (per share)</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_EscrowAccountMaintainedFor2008RestrictedStockPlan" xlink:to="msex_EscrowAccountMaintainedFor2008RestrictedStockPlan_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_EscrowAccountMaintainedFor2008RestrictedStockPlan_doc" xml:lang="en-US">Escrow account maintained for 2008 restricted stock plan</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ExpectedAmortizedActuarialLoss" xlink:to="msex_ExpectedAmortizedActuarialLoss_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_ExpectedAmortizedActuarialLoss_doc" xml:lang="en-US">Expected amount of gain (loss) related to change in benefit obligation resulting from changes in actuarial assumptions.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ExpectedAmortizedPriorServiceCredit" xlink:to="msex_ExpectedAmortizedPriorServiceCredit_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_ExpectedAmortizedPriorServiceCredit_doc" xml:lang="en-US">Expected amount of amortization of the net prior service credits.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage10Member" xlink:to="msex_FirstMortgage10Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_FirstMortgage10Member_doc" xml:lang="en-US">Loan secured by real property that has a first (highest) lien on such property in the event of default by the borrower.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage11Member" xlink:to="msex_FirstMortgage11Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_FirstMortgage11Member_doc" xml:lang="en-US">Loan secured by real property that has a first (highest) lien on such property in the event of default by the borrower.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage12Member" xlink:to="msex_FirstMortgage12Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_FirstMortgage12Member_doc" xml:lang="en-US">Loan secured by real property that has a first (highest) lien on such property in the event of default by the borrower.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage13Member" xlink:to="msex_FirstMortgage13Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_FirstMortgage13Member_doc" xml:lang="en-US">Loan secured by real property that has a first (highest) lien on such property in the event of default by the borrower.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage14Member" xlink:to="msex_FirstMortgage14Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_FirstMortgage14Member_doc" xml:lang="en-US">Loan secured by real property that has a first (highest) lien on such property in the event of default by the borrower.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage15Member" xlink:to="msex_FirstMortgage15Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_FirstMortgage15Member_doc" xml:lang="en-US">Loan secured by real property that has a first (highest) lien on such property in the event of default by the borrower.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage16Member" xlink:to="msex_FirstMortgage16Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_FirstMortgage16Member_doc" xml:lang="en-US">Loan secured by real property that has a first (highest) lien on such property in the event of default by the borrower.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage17Member" xlink:to="msex_FirstMortgage17Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_FirstMortgage17Member_doc" xml:lang="en-US">Loan secured by real property that has a first (highest) lien on such property in the event of default by the borrower.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage18Member" xlink:to="msex_FirstMortgage18Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_FirstMortgage18Member_doc" xml:lang="en-US">Loan secured by real property that has a first (highest) lien on such property in the event of default by the borrower.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage19Member" xlink:to="msex_FirstMortgage19Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_FirstMortgage19Member_doc" xml:lang="en-US">Loan secured by real property that has a first (highest) lien on such property in the event of default by the borrower.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage1Member" xlink:to="msex_FirstMortgage1Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_FirstMortgage1Member_doc" xml:lang="en-US">Loan secured by real property that has a first (highest) lien on such property in the event of default by the borrower.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage20Member" xlink:to="msex_FirstMortgage20Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_FirstMortgage20Member_doc" xml:lang="en-US">Loan secured by real property that has a first (highest) lien on such property in the event of default by the borrower.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage21Member" xlink:to="msex_FirstMortgage21Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_FirstMortgage21Member_doc" xml:lang="en-US">Loan secured by real property that has a first (highest) lien on such property in the event of default by the borrower.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage22Member" xlink:to="msex_FirstMortgage22Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_FirstMortgage22Member_doc" xml:lang="en-US">Loan secured by real property that has a first (highest) lien on such property in the event of default by the borrower.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage23Member" xlink:to="msex_FirstMortgage23Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_FirstMortgage23Member_doc" xml:lang="en-US">Loan secured by real property that has a first (highest) lien on such property in the event of default by the borrower.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage24Member" xlink:to="msex_FirstMortgage24Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_FirstMortgage24Member_doc" xml:lang="en-US">Loan secured by real property that has a first (highest) lien on such property in the event of default by the borrower.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage25Member" xlink:to="msex_FirstMortgage25Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_FirstMortgage25Member_doc" xml:lang="en-US">Loan secured by real property that has a first (highest) lien on such property in the event of default by the borrower.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage26Member" xlink:to="msex_FirstMortgage26Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_FirstMortgage26Member_doc" xml:lang="en-US">Loan secured by real property that has a first (highest) lien on such property in the event of default by the borrower.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage2Member" xlink:to="msex_FirstMortgage2Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_FirstMortgage2Member_doc" xml:lang="en-US">Loan secured by real property that has a first (highest) lien on such property in the event of default by the borrower.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage3Member" xlink:to="msex_FirstMortgage3Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_FirstMortgage3Member_doc" xml:lang="en-US">Loan secured by real property that has a first (highest) lien on such property in the event of default by the borrower.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage4Member" xlink:to="msex_FirstMortgage4Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_FirstMortgage4Member_doc" xml:lang="en-US">Loan secured by real property that has a first (highest) lien on such property in the event of default by the borrower.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage5Member" xlink:to="msex_FirstMortgage5Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_FirstMortgage5Member_doc" xml:lang="en-US">Loan secured by real property that has a first (highest) lien on such property in the event of default by the borrower.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage6Member" xlink:to="msex_FirstMortgage6Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_FirstMortgage6Member_doc" xml:lang="en-US">Loan secured by real property that has a first (highest) lien on such property in the event of default by the borrower.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage8Member" xlink:to="msex_FirstMortgage8Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_FirstMortgage8Member_doc" xml:lang="en-US">Loan secured by real property that has a first (highest) lien on such property in the event of default by the borrower.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage9Member" xlink:to="msex_FirstMortgage9Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_FirstMortgage9Member_doc" xml:lang="en-US">Loan secured by real property that has a first (highest) lien on such property in the event of default by the borrower.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgageBondsFairValueDisclosure" xlink:to="msex_FirstMortgageBondsFairValueDisclosure_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_FirstMortgageBondsFairValueDisclosure_doc" xml:lang="en-US">Represents the aggregate of the first mortgage bonds reported on the balance sheet at period end measured at fair value by the entity.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ForfeitedUnearnedCompensation" xlink:to="msex_ForfeitedUnearnedCompensation_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_ForfeitedUnearnedCompensation_doc" xml:lang="en-US">Amount of forfeitures of unearned compensation.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_GeneralPlantMember" xlink:to="msex_GeneralPlantMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_GeneralPlantMember_doc" xml:lang="en-US">General Plant</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_GrantedUnearnedCompensation" xlink:to="msex_GrantedUnearnedCompensation_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_GrantedUnearnedCompensation_doc" xml:lang="en-US">The grant-date value of unearned compensation.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_IncomeTaxesMember" xlink:to="msex_IncomeTaxesMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_IncomeTaxesMember_doc" xml:lang="en-US">Income Taxes</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_IncreaseDecreaseInAnnualRatePerCapitaCostOfCoveredHealthcareBenefitsYearsFourAndFive" xlink:to="msex_IncreaseDecreaseInAnnualRatePerCapitaCostOfCoveredHealthcareBenefitsYearsFourAndFive_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_IncreaseDecreaseInAnnualRatePerCapitaCostOfCoveredHealthcareBenefitsYearsFourAndFive_doc" xml:lang="en-US">Increase (decrease) in annual rate per capita cost of covered healthcare benefits, years four and five.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_IncreaseDecreaseInAnnualRatePerCapitaCostOfCoveredHealthcareBenefitsYearsOneToThree" xlink:to="msex_IncreaseDecreaseInAnnualRatePerCapitaCostOfCoveredHealthcareBenefitsYearsOneToThree_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_IncreaseDecreaseInAnnualRatePerCapitaCostOfCoveredHealthcareBenefitsYearsOneToThree_doc" xml:lang="en-US">Increase (decrease) in annual rate per capita cost of covered healthcare benefits,years one to three</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_IncreaseInBaseRatesRevenuePerYearPercent" xlink:to="msex_IncreaseInBaseRatesRevenuePerYearPercent_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_IncreaseInBaseRatesRevenuePerYearPercent_doc" xml:lang="en-US">Increase in base rates revenue per year, percent</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_IncrementalCommonSharesAttributableToConversionOfDollar7PreferredSeriesStock" xlink:to="msex_IncrementalCommonSharesAttributableToConversionOfDollar7PreferredSeriesStock_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_IncrementalCommonSharesAttributableToConversionOfDollar7PreferredSeriesStock_doc" xml:lang="en-US">Incremental common shares attributable to $7.00 series preferred shares, shares</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_IncrementalCommonSharesAttributableToConversionOfDollar8PreferredSeriesStock" xlink:to="msex_IncrementalCommonSharesAttributableToConversionOfDollar8PreferredSeriesStock_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_IncrementalCommonSharesAttributableToConversionOfDollar8PreferredSeriesStock_doc" xml:lang="en-US">Incremental common shares attributable to $8.00 series preferred shares, shares</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_InitialPaymentReceivedFromInsuranceClaim" xlink:to="msex_InitialPaymentReceivedFromInsuranceClaim_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_InitialPaymentReceivedFromInsuranceClaim_doc" xml:lang="en-US">Refers to initial payments received from insurance claim as result of superstorm sandy.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_InterimRates" xlink:to="msex_InterimRates_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_InterimRates_doc" xml:lang="en-US">Increase (decrease) in interim rates revenue.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_LoanAmountInitiallySetUpAsMarketbasedVariableInterestRateTransaction" xlink:to="msex_LoanAmountInitiallySetUpAsMarketbasedVariableInterestRateTransaction_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_LoanAmountInitiallySetUpAsMarketbasedVariableInterestRateTransaction_doc" xml:lang="en-US">Loan amount initially set up as a market-based variable interest rate transaction.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_LongtermPurchaseCommitmentExpirationDate" xlink:to="msex_LongtermPurchaseCommitmentExpirationDate_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_LongtermPurchaseCommitmentExpirationDate_doc" xml:lang="en-US">The expiration date of a long-term purchase commitment.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_MatchingContributions" xlink:to="msex_MatchingContributions_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_MatchingContributions_doc" xml:lang="en-US">Amount of employer's matching contributions to a defined contribution plan in a given year.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_MaximumAnnualRevenuesAllowedUnderFoundationalFiling" xlink:to="msex_MaximumAnnualRevenuesAllowedUnderFoundationalFiling_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_MaximumAnnualRevenuesAllowedUnderFoundationalFiling_doc" xml:lang="en-US">The maximum annual revenues allowed under Foundational filing.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_MiddlesexWaterCompanyMember" xlink:to="msex_MiddlesexWaterCompanyMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_MiddlesexWaterCompanyMember_doc" xml:lang="en-US">Middlesex</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_MinimumTreatedWaterPurchaseCommitment" xlink:to="msex_MinimumTreatedWaterPurchaseCommitment_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_MinimumTreatedWaterPurchaseCommitment_doc" xml:lang="en-US">The description of minimum treated water purchase commitment.</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_NetIncomeMember" xlink:label="msex_NetIncomeMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_NetIncomeMember" xlink:to="msex_NetIncomeMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_NetIncomeMember_doc" xml:lang="en-US">Net Income [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_NewConstructionLoansMember" xlink:to="msex_NewConstructionLoansMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_NewConstructionLoansMember_doc" xml:lang="en-US">Construction Loans [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_NewJerseyBoardOfPublicUtilitiesMember" xlink:to="msex_NewJerseyBoardOfPublicUtilitiesMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_NewJerseyBoardOfPublicUtilitiesMember_doc" xml:lang="en-US">New Jersey Board Of Public Utilities [Member].</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_NewJerseyEconomicDevelopmentAuthorityMember" xlink:to="msex_NewJerseyEconomicDevelopmentAuthorityMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_NewJerseyEconomicDevelopmentAuthorityMember_doc" xml:lang="en-US">New Jersey Economic Development Authority</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_NewJerseyEnvironmentalInfrastructureTrustMember" xlink:label="msex_NewJerseyEnvironmentalInfrastructureTrustMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_NewJerseyEnvironmentalInfrastructureTrustMember" xlink:to="msex_NewJerseyEnvironmentalInfrastructureTrustMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_NewJerseyEnvironmentalInfrastructureTrustMember_doc" xml:lang="en-US">New Jersey Environmental Infrastructure Trust</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_NonUtilityAssetsNet" xlink:to="msex_NonUtilityAssetsNet_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_NonUtilityAssetsNet_doc" xml:lang="en-US">Refers to amount of non utility fixed assets as of the balance sheet date.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_NonredeemablePreferredStock1Member" xlink:to="msex_NonredeemablePreferredStock1Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_NonredeemablePreferredStock1Member_doc" xml:lang="en-US">Preferred shares that are not redeemable before liquidation of the entity. Preferred shares may provide a preferential dividend to the dividend on common stock and may take precedence over common stock in the event of a liquidation. Preferred shares typically represent an ownership interest in the company.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_NumberOfCustomers" xlink:to="msex_NumberOfCustomers_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_NumberOfCustomers_doc" xml:lang="en-US">Number of customers</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_NumberOfHoursRequiredToParticipateInContributionPlan" xlink:to="msex_NumberOfHoursRequiredToParticipateInContributionPlan_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_NumberOfHoursRequiredToParticipateInContributionPlan_doc" xml:lang="en-US">Number of hours required to participate in contribution plan</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_OperationsAndMaintenance" xlink:to="msex_OperationsAndMaintenance_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_OperationsAndMaintenance_doc" xml:lang="en-US">Costs incurred and are directly related to operations and maintenance.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_OperationsContractsDeveloperAndOtherReceivables" xlink:to="msex_OperationsContractsDeveloperAndOtherReceivables_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_OperationsContractsDeveloperAndOtherReceivables_doc" xml:lang="en-US">Refers to amount of receivables under operations contracts or from developers that are not expected to be collected in less than one year.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_OrganizationSummaryOfSignificantAccountingPoliciesAndRecentDevelopmentsAbstract" xlink:to="msex_OrganizationSummaryOfSignificantAccountingPoliciesAndRecentDevelopmentsAbstract_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_OrganizationSummaryOfSignificantAccountingPoliciesAndRecentDevelopmentsAbstract_doc" xml:lang="en-US">Organization Summary Of Significant Accounting Policies And Recent Developments</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_OrganizationSummaryOfSignificantAccountingPoliciesAndRecentDevelopmentsLineItems" xlink:to="msex_OrganizationSummaryOfSignificantAccountingPoliciesAndRecentDevelopmentsLineItems_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_OrganizationSummaryOfSignificantAccountingPoliciesAndRecentDevelopmentsLineItems_doc" xml:lang="en-US">Organization, Summary of Significant Accounting Policies And Recent Developments [Line Items].</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_OrganizationSummaryOfSignificantAccountingPoliciesAndRecentDevelopmentsTable" xlink:to="msex_OrganizationSummaryOfSignificantAccountingPoliciesAndRecentDevelopmentsTable_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_OrganizationSummaryOfSignificantAccountingPoliciesAndRecentDevelopmentsTable_doc" xml:lang="en-US">Organization, Summary Of Significant Accounting Policies And Recent Developments [Table].</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_OriginallyFiledBaseWaterRateIncrease" xlink:to="msex_OriginallyFiledBaseWaterRateIncrease_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_OriginallyFiledBaseWaterRateIncrease_doc" xml:lang="en-US">The increased amount of originally filed base water rates.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_OtherLoanSourceMaximumBorrowingCapacity" xlink:to="msex_OtherLoanSourceMaximumBorrowingCapacity_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_OtherLoanSourceMaximumBorrowingCapacity_doc" xml:lang="en-US">The maximum borrowing amount for other loan sources not specifically stated in the taxonomy.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_OutsideDirectorStockCompensationPlanMember" xlink:to="msex_OutsideDirectorStockCompensationPlanMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_OutsideDirectorStockCompensationPlanMember_doc" xml:lang="en-US">Outside Director Stock Compensation Plan</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PercentOfOperatingRevenues" xlink:to="msex_PercentOfOperatingRevenues_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_PercentOfOperatingRevenues_doc" xml:lang="en-US">Percent of operating revenues.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PercentOfParticipantsContributionsMatchedByCompanyAboveOnePercentOfParticipantsCompensation" xlink:to="msex_PercentOfParticipantsContributionsMatchedByCompanyAboveOnePercentOfParticipantsCompensation_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_PercentOfParticipantsContributionsMatchedByCompanyAboveOnePercentOfParticipantsCompensation_doc" xml:lang="en-US">Percent of participants contributions matched by company, above one percent of participants compensation.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PercentOfParticipantsContributionsMatchedByCompanyBelowOnePercentOfParticipantsCompensation" xlink:to="msex_PercentOfParticipantsContributionsMatchedByCompanyBelowOnePercentOfParticipantsCompensation_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_PercentOfParticipantsContributionsMatchedByCompanyBelowOnePercentOfParticipantsCompensation_doc" xml:lang="en-US">Percent of participants contributions matched by company, below one percent of participants compensation.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PercentOfTotalAssets" xlink:to="msex_PercentOfTotalAssets_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_PercentOfTotalAssets_doc" xml:lang="en-US">Percent of total assets.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PercentVotingInterest" xlink:to="msex_PercentVotingInterest_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_PercentVotingInterest_doc" xml:lang="en-US">Percent of voting interest held.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PercentageOfPrincipalWithMarketInterestRate" xlink:to="msex_PercentageOfPrincipalWithMarketInterestRate_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_PercentageOfPrincipalWithMarketInterestRate_doc" xml:lang="en-US">The percentage of the loan balance that is subject to the market interest rate at the time of closing in the contractual debt agreement.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PercentageOfPrincipalWithStatedInterestRate" xlink:to="msex_PercentageOfPrincipalWithStatedInterestRate_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_PercentageOfPrincipalWithStatedInterestRate_doc" xml:lang="en-US">The percentage of the loan balance that is subject to the stated interest rate in the contractual debt agreement.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PercentageOfStockThatMayBeRedeemedInGivenCalanderYear" xlink:to="msex_PercentageOfStockThatMayBeRedeemedInGivenCalanderYear_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_PercentageOfStockThatMayBeRedeemedInGivenCalanderYear_doc" xml:lang="en-US">Percentage of stock that may be redeemed in a given calander year.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PinelandsCompanyMember" xlink:to="msex_PinelandsCompanyMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_PinelandsCompanyMember_doc" xml:lang="en-US">Pinelands Water</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PinelandsWastewaterMember" xlink:to="msex_PinelandsWastewaterMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_PinelandsWastewaterMember_doc" xml:lang="en-US">Pinelands Wastewater</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_PinelandsWaterAndPinelandsWastewaterMember" xlink:label="msex_PinelandsWaterAndPinelandsWastewaterMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PinelandsWaterAndPinelandsWastewaterMember" xlink:to="msex_PinelandsWaterAndPinelandsWastewaterMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_PinelandsWaterAndPinelandsWastewaterMember_doc" xml:lang="en-US">Pinelands Water and Pinelands Wastewater Member.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PreferredEquitySecuritiesMember" xlink:to="msex_PreferredEquitySecuritiesMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_PreferredEquitySecuritiesMember_doc" xml:lang="en-US">Preferred Equity Securities [Member].</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PreliminarySurveyAndInvestigationCharges" xlink:to="msex_PreliminarySurveyAndInvestigationCharges_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_PreliminarySurveyAndInvestigationCharges_doc" xml:lang="en-US">Deferred balance for preliminary survey charges and investigation charges.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PreliminarySurveyAndInvestigationPsiCostsPolicyTextBlock" xlink:to="msex_PreliminarySurveyAndInvestigationPsiCostsPolicyTextBlock_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_PreliminarySurveyAndInvestigationPsiCostsPolicyTextBlock_doc" xml:lang="en-US">Disclosure of accounting policy for preliminary survey and Investigation costs.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PremiumOnLongtermDebt" xlink:to="msex_PremiumOnLongtermDebt_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_PremiumOnLongtermDebt_doc" xml:lang="en-US">The cash inflow from amount of debt premium that was originally recognized at the issuance of the instrument .</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ProjectedAnnualRevenue" xlink:to="msex_ProjectedAnnualRevenue_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_ProjectedAnnualRevenue_doc" xml:lang="en-US">The projected annual revenue from new water operations.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PumpingMember" xlink:to="msex_PumpingMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_PumpingMember_doc" xml:lang="en-US">Pumping</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PurchaseCommitment1Member" xlink:to="msex_PurchaseCommitment1Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_PurchaseCommitment1Member_doc" xml:lang="en-US">Purchase Commitment1 [Member].</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PurchaseCommitment2Member" xlink:to="msex_PurchaseCommitment2Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_PurchaseCommitment2Member_doc" xml:lang="en-US">Purchase Commitment2 [Member].</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PurchaseOfWastewaterUtilityAssets" xlink:to="msex_PurchaseOfWastewaterUtilityAssets_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_PurchaseOfWastewaterUtilityAssets_doc" xml:lang="en-US">Refes to purchase of wastewater utility assets.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_RangeOfDepreciationRatesTableTextBlock" xlink:to="msex_RangeOfDepreciationRatesTableTextBlock_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_RangeOfDepreciationRatesTableTextBlock_doc" xml:lang="en-US">Schedule of range of depreciation rates.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_RateBase" xlink:to="msex_RateBase_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_RateBase_doc" xml:lang="en-US">Return on invested capital, rate base.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_RateCasesStormCostsTankPaintingOtherMember" xlink:to="msex_RateCasesStormCostsTankPaintingOtherMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_RateCasesStormCostsTankPaintingOtherMember_doc" xml:lang="en-US">Rate Cases, Storm Costs, Tank Painting, and Other</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_RecentDevelopmentsPolicyTextBlock" xlink:to="msex_RecentDevelopmentsPolicyTextBlock_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_RecentDevelopmentsPolicyTextBlock_doc" xml:lang="en-US">Accounting policy concerning recent company developments.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ReclassificationOfUnamortizedDebtExpenseDueToNewAccountingStandard" xlink:to="msex_ReclassificationOfUnamortizedDebtExpenseDueToNewAccountingStandard_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_ReclassificationOfUnamortizedDebtExpenseDueToNewAccountingStandard_doc" xml:lang="en-US">The amount of unamortized debt expense that was reclassified from assets to long-term debt during the period due to the adoption of new accounting standards.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ReimbursementsReceivedForPreliminarySurveyAndInvestigationCosts" xlink:to="msex_ReimbursementsReceivedForPreliminarySurveyAndInvestigationCosts_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_ReimbursementsReceivedForPreliminarySurveyAndInvestigationCosts_doc" xml:lang="en-US">Repayment received or receivable for costs incurred.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_RemainingRecoveryPeriod" xlink:to="msex_RemainingRecoveryPeriod_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_RemainingRecoveryPeriod_doc" xml:lang="en-US">The period remaining for recovery of costs in the rates we charge customers.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ReserveAgainstTangiblePropertyDeductions" xlink:to="msex_ReserveAgainstTangiblePropertyDeductions_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_ReserveAgainstTangiblePropertyDeductions_doc" xml:lang="en-US">Reserve against tangible property deductions.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_SecuredDebt1Member" xlink:to="msex_SecuredDebt1Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_SecuredDebt1Member_doc" xml:lang="en-US">Collateralized debt obligation backed by, for example, but not limited to, pledge, mortgage or other lien on the entity''s assets.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_SecuredDebt2Member" xlink:to="msex_SecuredDebt2Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_SecuredDebt2Member_doc" xml:lang="en-US">Collateralized debt obligation backed by, for example, but not limited to, pledge, mortgage or other lien on the entity''s assets.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_SecuredDebt3Member" xlink:to="msex_SecuredDebt3Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_SecuredDebt3Member_doc" xml:lang="en-US">Collateralized debt obligation backed by, for example, but not limited to, pledge, mortgage or other lien on the entity''s assets.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_SecuredDebt4Member" xlink:to="msex_SecuredDebt4Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_SecuredDebt4Member_doc" xml:lang="en-US">Collateralized debt obligation backed by, for example, but not limited to, pledge, mortgage or other lien on the entity''s assets.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_SecuredDebt5Member" xlink:to="msex_SecuredDebt5Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_SecuredDebt5Member_doc" xml:lang="en-US">Collateralized debt obligation backed by, for example, but not limited to, pledge, mortgage or other lien on the entity''s assets.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_SecuredDebt6Member" xlink:to="msex_SecuredDebt6Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_SecuredDebt6Member_doc" xml:lang="en-US">Collateralized debt obligation backed by, for example, but not limited to, pledge, mortgage or other lien on the entity''s assets.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_SecuredDebt7Member" xlink:to="msex_SecuredDebt7Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_SecuredDebt7Member_doc" xml:lang="en-US">Collateralized debt obligation backed by, for example, but not limited to, pledge, mortgage or other lien on the entity''s assets.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsWeightedAverageGrantDateValueUnearnedCompensation" xlink:to="msex_ShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsWeightedAverageGrantDateValueUnearnedCompensation_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_ShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsWeightedAverageGrantDateValueUnearnedCompensation_doc" xml:lang="en-US">The weighted average grant-date fair value of unearned compensation granted during the reporting period.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_SourceOfSupplyMember" xlink:to="msex_SourceOfSupplyMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_SourceOfSupplyMember_doc" xml:lang="en-US">Source of Supply</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_SouthernShoresMember" xlink:to="msex_SouthernShoresMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_SouthernShoresMember_doc" xml:lang="en-US">Southern Shores</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_StateRevolvingNotesFairValueDisclosure" xlink:to="msex_StateRevolvingNotesFairValueDisclosure_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_StateRevolvingNotesFairValueDisclosure_doc" xml:lang="en-US">Represents the aggregate of the state revolving notes reported on the balance sheet at period end measured at fair value by the entity.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_StateRevolvingTrustBond1Member" xlink:to="msex_StateRevolvingTrustBond1Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_StateRevolvingTrustBond1Member_doc" xml:lang="en-US">Refers to state revolving trust bond.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_StateRevolvingTrustBondMember" xlink:to="msex_StateRevolvingTrustBondMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_StateRevolvingTrustBondMember_doc" xml:lang="en-US">Refers to state revolving trust bond.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_StateRevolvingTrustNote10Member" xlink:to="msex_StateRevolvingTrustNote10Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_StateRevolvingTrustNote10Member_doc" xml:lang="en-US">State Revolving Trust Note, due February 1, 2036 [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_StateRevolvingTrustNote1Member" xlink:to="msex_StateRevolvingTrustNote1Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_StateRevolvingTrustNote1Member_doc" xml:lang="en-US">Refers to state revolving trust note.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_StateRevolvingTrustNote2Member" xlink:to="msex_StateRevolvingTrustNote2Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_StateRevolvingTrustNote2Member_doc" xml:lang="en-US">Refers to state revolving trust note.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_StateRevolvingTrustNote3Member" xlink:to="msex_StateRevolvingTrustNote3Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_StateRevolvingTrustNote3Member_doc" xml:lang="en-US">Refers to state revolving trust note.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_StateRevolvingTrustNote4Member" xlink:to="msex_StateRevolvingTrustNote4Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_StateRevolvingTrustNote4Member_doc" xml:lang="en-US">Refers to state revolving trust note.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_StateRevolvingTrustNote5Member" xlink:to="msex_StateRevolvingTrustNote5Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_StateRevolvingTrustNote5Member_doc" xml:lang="en-US">Refers to state revolving trust note.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_StateRevolvingTrustNote6Member" xlink:to="msex_StateRevolvingTrustNote6Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_StateRevolvingTrustNote6Member_doc" xml:lang="en-US">Refers to state revolving trust note.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_StateRevolvingTrustNote7Member" xlink:to="msex_StateRevolvingTrustNote7Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_StateRevolvingTrustNote7Member_doc" xml:lang="en-US">Refers to state revolving trust note.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_StateRevolvingTrustNote8Member" xlink:to="msex_StateRevolvingTrustNote8Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_StateRevolvingTrustNote8Member_doc" xml:lang="en-US">Refers to state revolving trust note.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_StateRevolvingTrustNote9Member" xlink:to="msex_StateRevolvingTrustNote9Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_StateRevolvingTrustNote9Member_doc" xml:lang="en-US">State Revolving Trust Note 9 [Member].</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_StateRevolvingTrustNoteMember" xlink:to="msex_StateRevolvingTrustNoteMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_StateRevolvingTrustNoteMember_doc" xml:lang="en-US">Refers to state revolving trust note.</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_StatementConsolidatedStatementsOfCapitalStockAndLongtermDebtAbstract" xlink:label="msex_StatementConsolidatedStatementsOfCapitalStockAndLongtermDebtAbstract" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_StatementConsolidatedStatementsOfCapitalStockAndLongtermDebtAbstract" xlink:to="msex_StatementConsolidatedStatementsOfCapitalStockAndLongtermDebtAbstract_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_StatementConsolidatedStatementsOfCapitalStockAndLongtermDebtAbstract_doc" xml:lang="en-US">Statement Consolidated Statements Of Capital Stock And Longterm Debt [Abstract]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_SuperstormSandyRelatedCosts" xlink:to="msex_SuperstormSandyRelatedCosts_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_SuperstormSandyRelatedCosts_doc" xml:lang="en-US">Refers to toal cost like labor, outside contractor costs, fuel, generator rental and other directly related expenses resulting from storm damage mitigation, repair, clean-up and restoration activities.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_SystemOfAccountsPolicyTextBlock" xlink:to="msex_SystemOfAccountsPolicyTextBlock_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_SystemOfAccountsPolicyTextBlock_doc" xml:lang="en-US">Disclosure of accounting policy for system of accounts.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_TDMainsMember" xlink:to="msex_TDMainsMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_TDMainsMember_doc" xml:lang="en-US">T&amp;amp;amp;amp;D - Mains</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_TDOtherMember" xlink:to="msex_TDOtherMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_TDOtherMember_doc" xml:lang="en-US">T&amp;amp;amp;amp;D - Other</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_TDServicesMember" xlink:to="msex_TDServicesMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_TDServicesMember_doc" xml:lang="en-US">T&amp;amp;amp;amp;D - Services</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_TaxEffectOfAbstract" xlink:to="msex_TaxEffectOfAbstract_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_TaxEffectOfAbstract_doc" xml:lang="en-US">Tax Effect of:</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_TermOfAgreement" xlink:to="msex_TermOfAgreement_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_TermOfAgreement_doc" xml:lang="en-US">Refers to term of agreement.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ThresholdPercentageOfParticipantsCompensationAtWhichMatchingDecreases" xlink:to="msex_ThresholdPercentageOfParticipantsCompensationAtWhichMatchingDecreases_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_ThresholdPercentageOfParticipantsCompensationAtWhichMatchingDecreases_doc" xml:lang="en-US">Threshold percentage of participants compensation at which matching decreases.</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_TidewaterEnvironmentalServicesMember" xlink:label="msex_TidewaterEnvironmentalServicesMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_TidewaterEnvironmentalServicesMember" xlink:to="msex_TidewaterEnvironmentalServicesMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_TidewaterEnvironmentalServicesMember_doc" xml:lang="en-US">TESI</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_TidewaterMember" xlink:to="msex_TidewaterMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_TidewaterMember_doc" xml:lang="en-US">Tidewater [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_TidewaterUtilitiesIncMember" xlink:to="msex_TidewaterUtilitiesIncMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_TidewaterUtilitiesIncMember_doc" xml:lang="en-US">Tidewater</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_TotalCommonEquity" xlink:to="msex_TotalCommonEquity_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_TotalCommonEquity_doc" xml:lang="en-US">Refers to total equity attributable to common stockholders.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_TwinLakesMember" xlink:to="msex_TwinLakesMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_TwinLakesMember_doc" xml:lang="en-US">Twin Lakes</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_UnearnedCompensationAbstract" xlink:to="msex_UnearnedCompensationAbstract_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_UnearnedCompensationAbstract_doc" xml:lang="en-US">Unearned Compensation [Abstract].</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_VestedUnearnedCompensation" xlink:to="msex_VestedUnearnedCompensation_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_VestedUnearnedCompensation_doc" xml:lang="en-US">The grant-date value of unearned compensation for awards vested.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_WastewaterCollectionMember" xlink:to="msex_WastewaterCollectionMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_WastewaterCollectionMember_doc" xml:lang="en-US">Wastewater Collection [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_WaterTreatmentMember" xlink:to="msex_WaterTreatmentMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_WaterTreatmentMember_doc" xml:lang="en-US">Water Treatment</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_WeightedAverageAssumptionsAbstract" xlink:to="msex_WeightedAverageAssumptionsAbstract_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_WeightedAverageAssumptionsAbstract_doc" xml:lang="en-US">Weighted Average Assumptions:</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_SecuredDebt7AMember" xlink:label="msex_SecuredDebt7AMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_SecuredDebt7AMember" xlink:to="msex_SecuredDebt7AMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_SecuredDebt7AMember_doc" xml:lang="en-US">4.47%, Amortizing Secured Note, due April 20, 2040 [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_FirstMortgage26XXMember" xlink:label="msex_FirstMortgage26XXMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage26XXMember" xlink:to="msex_FirstMortgage26XXMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_FirstMortgage26XXMember_doc" xml:lang="en-US">First Mortgage Bonds - Series XX [Member]</link:label>
      <link:loc xlink:type="locator" xlink:href="msex-20171231.xsd#msex_FirstMortgage26YYMember" xlink:label="msex_FirstMortgage26YYMember" />
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage26YYMember" xlink:to="msex_FirstMortgage26YYMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_FirstMortgage26YYMember_doc" xml:lang="en-US">First Mortgage Bonds - Series YY [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_SecuredDebt7April2Member" xlink:to="msex_SecuredDebt7April2Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_SecuredDebt7April2Member_doc" xml:lang="en-US">4.47%, Amortizing Secured Note, due April 20, 2040 [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage27Member" xlink:to="msex_FirstMortgage27Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_FirstMortgage27Member_doc" xml:lang="en-US">First Mortgage Bonds - Series XX [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_FirstMortgage28Member" xlink:to="msex_FirstMortgage28Member_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_FirstMortgage28Member_doc" xml:lang="en-US">First Mortgage Bonds - Series YY [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_TariffRateToRecoverAdditionalAnnualCosts" xlink:to="msex_TariffRateToRecoverAdditionalAnnualCosts_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_TariffRateToRecoverAdditionalAnnualCosts_doc" xml:lang="en-US">Tariff rate to recover additional annual costs</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PercentageOfCorporateTaxRegulatedCompainesPretax" xlink:to="msex_PercentageOfCorporateTaxRegulatedCompainesPretax_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_PercentageOfCorporateTaxRegulatedCompainesPretax_doc" xml:lang="en-US">Percentage of corporate tax regulated compaines pre-tax.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_ContributionsInAidOfConstructionCiacPolicyTextBlock" xlink:to="msex_ContributionsInAidOfConstructionCiacPolicyTextBlock_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_ContributionsInAidOfConstructionCiacPolicyTextBlock_doc" xml:lang="en-US">Contributions in Aid of Construction (CIAC).</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_NewJerseyInfrastructureBankMember" xlink:to="msex_NewJerseyInfrastructureBankMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_NewJerseyInfrastructureBankMember_doc" xml:lang="en-US">New Jersey Infrastructure Bank [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_SeriesXXMember" xlink:to="msex_SeriesXXMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_SeriesXXMember_doc" xml:lang="en-US">Series XX [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_PercentageOfPrincipalWithBondInterestRate" xlink:to="msex_PercentageOfPrincipalWithBondInterestRate_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_PercentageOfPrincipalWithBondInterestRate_doc" xml:lang="en-US">Percentage of principal with bond interest rate.</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_SeriesYYMember" xlink:to="msex_SeriesYYMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_SeriesYYMember_doc" xml:lang="en-US">Series YY [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_NewJerseyInfrastructureBankTwoMember" xlink:to="msex_NewJerseyInfrastructureBankTwoMember_doc" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:label="msex_NewJerseyInfrastructureBankTwoMember_doc" xml:lang="en-US">New Jersey Infrastructure Bank [Member]</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_TidewaterMember" xlink:to="msex_TidewaterMember_3_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_TidewaterMember_3_lbl" xml:lang="en-US">TidewaterMember</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_NewJerseyInfrastructureBankTwoMember" xlink:to="msex_NewJerseyInfrastructureBankTwoMember_3_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_NewJerseyInfrastructureBankTwoMember_3_lbl" xml:lang="en-US">NewJerseyInfrastructureBankTwoMember</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OperatingExpenses" xlink:to="us-gaap_OperatingExpenses_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OperatingExpenses_2_lbl" xml:lang="en-US">Operating Expenses</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherExpenses" xlink:to="us-gaap_OtherExpenses_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OtherExpenses_2_lbl" xml:lang="en-US">Other Expenses</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_NonoperatingIncomeExpense" xlink:to="us-gaap_NonoperatingIncomeExpense_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_NonoperatingIncomeExpense_2_lbl" xml:lang="en-US">Nonoperating Income (Expense)</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PublicUtilitiesPropertyPlantAndEquipmentPlantInService" xlink:to="us-gaap_PublicUtilitiesPropertyPlantAndEquipmentPlantInService_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PublicUtilitiesPropertyPlantAndEquipmentPlantInService_2_lbl" xml:lang="en-US">Public Utilities, Property, Plant and Equipment, Plant in Service</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PublicUtilitiesPropertyPlantAndEquipmentNet" xlink:to="us-gaap_PublicUtilitiesPropertyPlantAndEquipmentNet_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PublicUtilitiesPropertyPlantAndEquipmentNet_2_lbl" xml:lang="en-US">Public Utilities, Property, Plant and Equipment, Net</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_AssetsCurrent" xlink:to="us-gaap_AssetsCurrent_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_AssetsCurrent_2_lbl" xml:lang="en-US">Assets, Current</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="msex_DeferredChargesAndOtherAssets" xlink:to="msex_DeferredChargesAndOtherAssets_3_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="msex_DeferredChargesAndOtherAssets_3_lbl" xml:lang="en-US">Deferred Charges And Other Assets</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_CapitalizationLongtermDebtAndEquity" xlink:to="us-gaap_CapitalizationLongtermDebtAndEquity_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_CapitalizationLongtermDebtAndEquity_2_lbl" xml:lang="en-US">Capitalization, Long-term Debt and Equity</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherLiabilitiesCurrent" xlink:to="us-gaap_OtherLiabilitiesCurrent_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OtherLiabilitiesCurrent_2_lbl" xml:lang="en-US">Other Liabilities, Current</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LiabilitiesCurrent" xlink:to="us-gaap_LiabilitiesCurrent_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LiabilitiesCurrent_2_lbl" xml:lang="en-US">Liabilities, Current</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_OtherLiabilitiesNoncurrent" xlink:to="us-gaap_OtherLiabilitiesNoncurrent_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_OtherLiabilitiesNoncurrent_2_lbl" xml:lang="en-US">Other Liabilities, Noncurrent</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LiabilitiesOtherThanLongtermDebtNoncurrent" xlink:to="us-gaap_LiabilitiesOtherThanLongtermDebtNoncurrent_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LiabilitiesOtherThanLongtermDebtNoncurrent_2_lbl" xml:lang="en-US">Liabilities, Other than Long-term Debt, Noncurrent</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LiabilitiesAndStockholdersEquity" xlink:to="us-gaap_LiabilitiesAndStockholdersEquity_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LiabilitiesAndStockholdersEquity_2_lbl" xml:lang="en-US">Liabilities and Equity</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity" xlink:to="us-gaap_PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_PublicUtilitiesAllowanceForFundsUsedDuringConstructionCapitalizedCostOfEquity_2_lbl" xml:lang="en-US">Public Utilities, Allowance for Funds Used During Construction, Capitalized Cost of Equity</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_LifeInsuranceCorporateOrBankOwnedChangeInValue" xlink:to="us-gaap_LifeInsuranceCorporateOrBankOwnedChangeInValue_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_LifeInsuranceCorporateOrBankOwnedChangeInValue_2_lbl" xml:lang="en-US">Life Insurance, Corporate or Bank Owned, Change in Value</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInAccountsReceivable" xlink:to="us-gaap_IncreaseDecreaseInAccountsReceivable_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncreaseDecreaseInAccountsReceivable_2_lbl" xml:lang="en-US">Increase (Decrease) in Accounts Receivable</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInUnbilledReceivables" xlink:to="us-gaap_IncreaseDecreaseInUnbilledReceivables_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncreaseDecreaseInUnbilledReceivables_2_lbl" xml:lang="en-US">Increase (Decrease) in Unbilled Receivables</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInRawMaterialsPackagingMaterialsAndSuppliesInventories" xlink:to="us-gaap_IncreaseDecreaseInRawMaterialsPackagingMaterialsAndSuppliesInventories_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncreaseDecreaseInRawMaterialsPackagingMaterialsAndSuppliesInventories_2_lbl" xml:lang="en-US">Increase (Decrease) in Raw Materials, Packaging Materials and Supplies Inventories</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInPrepaidExpense" xlink:to="us-gaap_IncreaseDecreaseInPrepaidExpense_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncreaseDecreaseInPrepaidExpense_2_lbl" xml:lang="en-US">Increase (Decrease) in Prepaid Expense</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInAccountsPayable" xlink:to="us-gaap_IncreaseDecreaseInAccountsPayable_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncreaseDecreaseInAccountsPayable_2_lbl" xml:lang="en-US">Increase (Decrease) in Accounts Payable</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInAccruedTaxesPayable" xlink:to="us-gaap_IncreaseDecreaseInAccruedTaxesPayable_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncreaseDecreaseInAccruedTaxesPayable_2_lbl" xml:lang="en-US">Increase (Decrease) in Accrued Taxes Payable</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInInterestPayableNet" xlink:to="us-gaap_IncreaseDecreaseInInterestPayableNet_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncreaseDecreaseInInterestPayableNet_2_lbl" xml:lang="en-US">Increase (Decrease) in Interest Payable, Net</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInPensionAndPostretirementObligations" xlink:to="us-gaap_IncreaseDecreaseInPensionAndPostretirementObligations_2_lbl" xlink:type="arc" />
      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_IncreaseDecreaseInPensionAndPostretirementObligations_2_lbl" xml:lang="en-US">Increase (Decrease) in Obligation, Pension and Other Postretirement Benefits</link:label>
      <link:labelArc xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="us-gaap_IncreaseDecreaseInOtherReceivables" xlink:to="us-gaap_IncreaseDecreaseInOtherReceivables_2_lbl" xlink:type="arc" />
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      <link:label xlink:type="resource" xlink:role="http://www.xbrl.org/2003/role/label" xlink:label="us-gaap_RegulatoryAssets_2_lbl" xml:lang="en-US">Regulatory Assets [Default Label]</link:label>
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