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    <element id="msex_InterSegmentEliminationOperatingRevenues" name="InterSegmentEliminationOperatingRevenues" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="msex_BudgetedConstructionCost" name="BudgetedConstructionCost" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="msex_LongtermPurchaseCommitmentExpirationDate" name="LongtermPurchaseCommitmentExpirationDate" nillable="true" xbrli:periodType="duration" type="xbrli:dateItemType" substitutionGroup="xbrli:item" />
    <element id="msex_TotalCommonEquity" name="TotalCommonEquity" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="msex_CapitalizationTextBlock" name="CapitalizationTextBlock" nillable="true" xbrli:periodType="duration" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="msex_ReserveProvision" name="ReserveProvision" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="msex_BaseRateAmount" name="BaseRateAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="msex_TariffRateToRecoverAdditionalAnnualCosts" name="TariffRateToRecoverAdditionalAnnualCosts" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="msex_OtherLoanSourceMaximumBorrowingCapacity" name="OtherLoanSourceMaximumBorrowingCapacity" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="msex_ConstructionLoanMaximumBorrowingCapacity" name="ConstructionLoanMaximumBorrowingCapacity" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="msex_PercentageOfOfferingSharesOnDiscountToParticipants" name="PercentageOfOfferingSharesOnDiscountToParticipants" nillable="true" xbrli:periodType="duration" type="num:percentItemType" substitutionGroup="xbrli:item" />
    <element id="msex_PercentageOfPrincipalWithStatedInterestRate" name="PercentageOfPrincipalWithStatedInterestRate" nillable="true" xbrli:periodType="duration" type="num:percentItemType" substitutionGroup="xbrli:item" />
    <element id="msex_PercentageOfPrincipalWithMarketInterestRate" name="PercentageOfPrincipalWithMarketInterestRate" nillable="true" xbrli:periodType="duration" type="num:percentItemType" substitutionGroup="xbrli:item" />
    <element id="msex_CashDividendsOnCommonStockShares" name="CashDividendsOnCommonStockShares" nillable="true" xbrli:periodType="duration" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" />
    <element id="msex_CashDividendsOnPreferredStockShares" name="CashDividendsOnPreferredStockShares" nillable="true" xbrli:periodType="duration" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" />
    <element id="msex_CommonStockExpensesShares" name="CommonStockExpensesShares" nillable="true" xbrli:periodType="duration" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" />
    <element id="msex_ChangeInUnbilledRevenues" name="ChangeInUnbilledRevenues" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="msex_DeferredChargesAndOtherAssets" name="DeferredChargesAndOtherAssets" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="msex_NonUtilityAssetsNet" name="NonUtilityAssetsNet" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="msex_PreliminarySurveyAndInvestigationCharges" name="PreliminarySurveyAndInvestigationCharges" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="msex_ConstructionAdvances" name="ConstructionAdvances" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="msex_AdoptionOfRightOfUseAsset" name="AdoptionOfRightOfUseAsset" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="msex_AdoptionOfLeaseLiability" name="AdoptionOfLeaseLiability" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="msex_EstimatedIncrementalBorrowingRate" name="EstimatedIncrementalBorrowingRate" nillable="true" xbrli:periodType="instant" type="num:percentItemType" substitutionGroup="xbrli:item" />
    <element id="msex_ImputedInterest" name="ImputedInterest" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="msex_OperatingLeaseLiabilityAndOtherLiabilitiesCurrent" name="OperatingLeaseLiabilityAndOtherLiabilitiesCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="msex_RightOfUseAssetsCurrent" name="RightOfUseAssetsCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="msex_RightOfUseAssetAtLeaseInception" name="RightOfUseAssetAtLeaseInception" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="msex_RightOfUseAssetsAccumulatedAmortization" name="RightOfUseAssetsAccumulatedAmortization" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="msex_LeaseMaturityDate" name="LeaseMaturityDate" nillable="true" xbrli:periodType="duration" type="xbrli:gYearItemType" substitutionGroup="xbrli:item" />
    <element id="msex_ConvertiblePreferredStock1Member" name="ConvertiblePreferredStock1Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_NonredeemablePreferredStock1Member" name="NonredeemablePreferredStock1Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_StateRevolvingTrustNote10Member" name="StateRevolvingTrustNote10Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_FirstMortgage21Member" name="FirstMortgage21Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_FirstMortgage22Member" name="FirstMortgage22Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_FirstMortgage23Member" name="FirstMortgage23Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_FirstMortgage24Member" name="FirstMortgage24Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_FirstMortgage25Member" name="FirstMortgage25Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_FirstMortgage26Member" name="FirstMortgage26Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_FirstMortgage15Member" name="FirstMortgage15Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_FirstMortgage16Member" name="FirstMortgage16Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_FirstMortgage17Member" name="FirstMortgage17Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_FirstMortgage18Member" name="FirstMortgage18Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_FirstMortgage19Member" name="FirstMortgage19Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_FirstMortgage20Member" name="FirstMortgage20Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_FirstMortgage9Member" name="FirstMortgage9Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_FirstMortgage10Member" name="FirstMortgage10Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_FirstMortgage11Member" name="FirstMortgage11Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_FirstMortgage12Member" name="FirstMortgage12Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_FirstMortgage13Member" name="FirstMortgage13Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_FirstMortgage14Member" name="FirstMortgage14Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_FirstMortgage2Member" name="FirstMortgage2Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_FirstMortgage3Member" name="FirstMortgage3Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_FirstMortgage4Member" name="FirstMortgage4Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_FirstMortgage5Member" name="FirstMortgage5Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_FirstMortgage6Member" name="FirstMortgage6Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_FirstMortgage8Member" name="FirstMortgage8Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_SecuredDebt5Member" name="SecuredDebt5Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_SecuredDebt6Member" name="SecuredDebt6Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_SecuredDebt7Member" name="SecuredDebt7Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_StateRevolvingTrustNote7Member" name="StateRevolvingTrustNote7Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_StateRevolvingTrustNote8Member" name="StateRevolvingTrustNote8Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_FirstMortgage1Member" name="FirstMortgage1Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_StateRevolvingTrustBondMember" name="StateRevolvingTrustBondMember" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_StateRevolvingTrustBond1Member" name="StateRevolvingTrustBond1Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_StateRevolvingTrustNote4Member" name="StateRevolvingTrustNote4Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_StateRevolvingTrustNote5Member" name="StateRevolvingTrustNote5Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_StateRevolvingTrustNote6Member" name="StateRevolvingTrustNote6Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_SecuredDebt4Member" name="SecuredDebt4Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_SecuredDebt3Member" name="SecuredDebt3Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_StateRevolvingTrustNoteMember" name="StateRevolvingTrustNoteMember" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_StateRevolvingTrustNote1Member" name="StateRevolvingTrustNote1Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_StateRevolvingTrustNote9Member" name="StateRevolvingTrustNote9Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_StateRevolvingTrustNote2Member" name="StateRevolvingTrustNote2Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_StateRevolvingTrustNote3Member" name="StateRevolvingTrustNote3Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_SecuredDebtZeroMember" name="SecuredDebtZeroMember" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_SecuredDebt1Member" name="SecuredDebt1Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_SecuredDebt2Member" name="SecuredDebt2Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_SecuredDebt10Member" name="SecuredDebt10Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_NewConstructionLoansMember" name="NewConstructionLoansMember" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_TidewaterUtilitiesIncMember" name="TidewaterUtilitiesIncMember" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_SecuredDebt11Member" name="SecuredDebt11Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_NewJerseySrfProgramMember" name="NewJerseySrfProgramMember" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_TwothousandsSeventeenRenewProgramMember" name="TwothousandsSeventeenRenewProgramMember" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_SecuredDebt8Member" name="SecuredDebt8Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_StateRevolvingFundBondMember" name="StateRevolvingFundBondMember" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_NetIncomeMember" name="NetIncomeMember" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_MiddlesexMember" name="MiddlesexMember" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_NewJerseyNjibProgramMember" name="NewJerseyNjibProgramMember" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_FirstMortgagesOneMember" name="FirstMortgagesOneMember" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_FirstMortgagesTwoMember" name="FirstMortgagesTwoMember" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_PurchaseCommitment1Member" name="PurchaseCommitment1Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_PurchaseCommitment2Member" name="PurchaseCommitment2Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_NewJerseyBoardOfPublicUtilitiesMember" name="NewJerseyBoardOfPublicUtilitiesMember" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_DelawareStateRevolvingFundMember" name="DelawareStateRevolvingFundMember" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_NewJerseyInfrastructureBankTwoMember" name="NewJerseyInfrastructureBankTwoMember" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_FirstMortgage27Member" name="FirstMortgage27Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_FirstMortgage28Member" name="FirstMortgage28Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_FirstMortgage29Member" name="FirstMortgage29Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_FirstMortgage31Member" name="FirstMortgage31Member" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_FirstMortgagesThreeMember" name="FirstMortgagesThreeMember" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_FirstMortgagesFourMember" name="FirstMortgagesFourMember" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_FirstMortgagesFiveMember" name="FirstMortgagesFiveMember" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_TidewaterMember" name="TidewaterMember" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_DelawarePublicServiceCommissionMember" name="DelawarePublicServiceCommissionMember" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_PinelandsCompanyMember" name="PinelandsCompanyMember" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_PinelandsWastewaterMember" name="PinelandsWastewaterMember" nillable="true" xbrli:periodType="duration" type="nonnum:domainItemType" substitutionGroup="xbrli:item" />
    <element id="msex_DocumentAndEntityInformationAbstract" name="DocumentAndEntityInformationAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="msex_DeferredChargesAndOtherAssetsAbstract" name="DeferredChargesAndOtherAssetsAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="msex_CashPaidDuringYearForAbstract" name="CashPaidDuringYearForAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="msex_CondensedConsolidatedStatementsOfCapitalStockAndLongtermDebtAbstract" name="CondensedConsolidatedStatementsOfCapitalStockAndLongtermDebtAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="msex_StatementConsolidatedStatementsOfCapitalStockAndLongtermDebtAbstract" name="StatementConsolidatedStatementsOfCapitalStockAndLongtermDebtAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="msex_BasisOfPresentationAndRecentDevelopmentsAbstract" name="BasisOfPresentationAndRecentDevelopmentsAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="msex_WastewaterSystemDescription" name="WastewaterSystemDescription" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="msex_ProjectedAnnualRevenue" name="ProjectedAnnualRevenue" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="msex_RecoverAdditionalCosts" name="RecoverAdditionalCosts" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="msex_PercentageOfPrincipalWithBondInterestRate" name="PercentageOfPrincipalWithBondInterestRate" nillable="true" xbrli:periodType="duration" type="num:percentItemType" substitutionGroup="xbrli:item" />
    <element id="msex_CostOfPurchasedWaterAbstract" name="CostOfPurchasedWaterAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
</schema>
