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  <xsd:element id="swx_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestBeforeTax" name="StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestBeforeTax" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
  <xsd:element id="swx_StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestTax" name="StockholdersEquityIncludingPortionAttributableToNoncontrollingInterestTax" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant" />
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  <xsd:element abstract="true" id="swx_UnitPricedContractsMember" name="UnitPricedContractsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="swx_UtilityInfrastructureServicesSegmentMember" name="UtilityInfrastructureServicesSegmentMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="swx_VariableRateBondsTaxExemptSeriesADueTwoThousandAndTwentyEightMember" name="VariableRateBondsTaxExemptSeriesADueTwoThousandAndTwentyEightMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="swx_VariableRateBondsTwoThousandAndEightSeriesADueTwoThousandAndThirtyEightMember" name="VariableRateBondsTwoThousandAndEightSeriesADueTwoThousandAndThirtyEightMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="swx_VariableRateBondsTwoThousandAndNineSeriesADueTwoThousandAndThirtyNineMember" name="VariableRateBondsTwoThousandAndNineSeriesADueTwoThousandAndThirtyNineMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
  <xsd:element abstract="true" id="swx_VariableRateBondsTwoThousandAndThreeSeriesADueTwoThousandAndThirtyEightMember" name="VariableRateBondsTwoThousandAndThreeSeriesADueTwoThousandAndThirtyEightMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration" />
</xsd:schema>
