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    <element id="MSEX_N500To550SeriesLLDueAugust12028" name="N500To550SeriesLLDueAugust12028" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="MSEX_N000SeriesMMDueAugust12030" name="N000SeriesMMDueAugust12030" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="MSEX_N300To4375SeriesNNDueAugust12030" name="N300To4375SeriesNNDueAugust12030" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="MSEX_CommonStockExpenses" name="CommonStockExpenses" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" />
    <element id="MSEX_OrganizationSummaryOfSignificantAccountingPoliciesAbstract" name="OrganizationSummaryOfSignificantAccountingPoliciesAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="MSEX_RateMattersAbstract" name="RateMattersAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="MSEX_RateMattersTextBlock" name="RateMattersTextBlock" nillable="true" xbrli:periodType="duration" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="MSEX_IncomeTaxesAbstract" name="IncomeTaxesAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="MSEX_CommitmentsAndContingentLiabilitiesAbstract" name="CommitmentsAndContingentLiabilitiesAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="MSEX_CapitalizationAbstract" name="CapitalizationAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="MSEX_CapitalizationTextBlock" name="CapitalizationTextBlock" nillable="true" xbrli:periodType="duration" type="nonnum:textBlockItemType" substitutionGroup="xbrli:item" />
    <element id="MSEX_EmployeeBenefitPlansAbstract" name="EmployeeBenefitPlansAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="MSEX_BusinessSegmentDataAbstract" name="BusinessSegmentDataAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
    <element id="MSEX_QuarterlyOperatingResultsUnauditedAbstract" name="QuarterlyOperatingResultsUnauditedAbstract" abstract="true" nillable="true" xbrli:periodType="duration" type="xbrli:stringItemType" substitutionGroup="xbrli:item" />
</schema>
