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  <xs:element name="TotalElectricReportableSegmentsMember" id="uil_TotalElectricReportableSegmentsMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="GasDistributionReportableSegmentMember" id="uil_GasDistributionReportableSegmentMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="DistributionSegmentMember" id="uil_DistributionSegmentMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="TransmissionSegmentMember" id="uil_TransmissionSegmentMember" type="nonnum:domainItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="CostOfPurchasedPowerAndGas" id="uil_CostOfPurchasedPowerAndGas" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" xbrli:balance="debit" />
  <xs:element name="NumberOfReportingSegments" id="uil_NumberOfReportingSegments" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="duration" />
  <xs:element name="NetPlantInServiceSegregatedBySegmentAbstract" id="uil_NetPlantInServiceSegregatedBySegmentAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" abstract="true" xbrli:periodType="duration" />
  <xs:element name="NetPlantInService" id="uil_NetPlantInService" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" />
  <xs:element name="SubcontractorsResponsibleForCivilConstruction" id="uil_SubcontractorsResponsibleForCivilConstruction" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="instant" />
  <xs:element name="RevisedAmountSoughtForChangeOrderRequests" id="uil_RevisedAmountSoughtForChangeOrderRequests" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" abstract="false" xbrli:periodType="instant" xbrli:balance="debit" />
</xs:schema>
