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  <xs:element id="smlp_RedemptionOptionTwoMember" abstract="true" name="RedemptionOptionTwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="smlp_AggregateCommitmentsPercentage" abstract="false" name="AggregateCommitmentsPercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="smlp_DebtInstrumentCovenantFirstLienNetLeverageRatio" abstract="false" name="DebtInstrumentCovenantFirstLienNetLeverageRatio" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="smlp_DebtInstrumentCovenantInterestCoverageRatio" abstract="false" name="DebtInstrumentCovenantInterestCoverageRatio" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="smlp_DebtInstrumentIssuedAsAPercentageOfFaceValue" abstract="false" name="DebtInstrumentIssuedAsAPercentageOfFaceValue" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="smlp_DebtInstrumentRedemptionPriceOfferAmount" abstract="false" name="DebtInstrumentRedemptionPriceOfferAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="smlp_DebtInstrumentTenderedAndValidlyAcceptedAndFullyDischargedAmount" abstract="false" name="DebtInstrumentTenderedAndValidlyAcceptedAndFullyDischargedAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="smlp_DebtInstrumentCovenantExcessCashFlowOfferToPurchaseAssetSaleOfferExpired" abstract="false" name="DebtInstrumentCovenantExcessCashFlowOfferToPurchaseAssetSaleOfferExpired" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="smlp_DebtInstrumentNoticeOfRedemptionOnTenderOfferRedemptionAmount" abstract="false" name="DebtInstrumentNoticeOfRedemptionOnTenderOfferRedemptionAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="smlp_DebtInstrumentRedemptionIrrevocableDeposit" abstract="false" name="DebtInstrumentRedemptionIrrevocableDeposit" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="smlp_DebtInstrumentRedemptionNoticeAmount" abstract="false" name="DebtInstrumentRedemptionNoticeAmount" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="smlp_LongTermDebtMaturityYearOneAdjusted" abstract="false" name="LongTermDebtMaturityYearOneAdjusted" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="smlp_LongTermDebtMaturityAfterYearFour" abstract="false" name="LongTermDebtMaturityAfterYearFour" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="smlp_DebtInstrumentsRedemptionPeriodOneMember" abstract="true" name="DebtInstrumentsRedemptionPeriodOneMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="smlp_DebtInstrumentsRedemptionPeriodTwoMember" abstract="true" name="DebtInstrumentsRedemptionPeriodTwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="smlp_DebtInstrumentRedemptionPeriodAfterTwoMember" abstract="true" name="DebtInstrumentRedemptionPeriodAfterTwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="smlp_MeadowlarkMidstreamGatheringSystemMember" abstract="true" name="MeadowlarkMidstreamGatheringSystemMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="smlp_A2015BlacktailReleaseMember" abstract="true" name="A2015BlacktailReleaseMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="smlp_NaturalResourceDamagesToFederalAndStateGovernmentsMember" abstract="true" name="NaturalResourceDamagesToFederalAndStateGovernmentsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="smlp_DamagesPayableToFederalGovernmentOverFiveYearsMember" abstract="true" name="DamagesPayableToFederalGovernmentOverFiveYearsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="smlp_DamagesPayableToStateGovernmentsOverSixYearsMember" abstract="true" name="DamagesPayableToStateGovernmentsOverSixYearsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="smlp_DamagesPayableToFederalCriminalOverFiveYearsMember" abstract="true" name="DamagesPayableToFederalCriminalOverFiveYearsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="smlp_EnvironmentalLossContingenciesPenaltiesAndFinesPaymentPeriod" abstract="false" name="EnvironmentalLossContingenciesPenaltiesAndFinesPaymentPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="smlp_PartnersCapitalTable" abstract="true" name="PartnersCapitalTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="smlp_SummitMidstreamPartnersLPMember" abstract="true" name="SummitMidstreamPartnersLPMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="smlp_MoonriseMember" abstract="true" name="MoonriseMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="smlp_LimitedPartnerCommonUnitsMember" abstract="true" name="LimitedPartnerCommonUnitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="smlp_PartnersCapitalLineItems" abstract="true" name="PartnersCapitalLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="smlp_AccruedAndUnpaidDistributions" abstract="false" name="AccruedAndUnpaidDistributions" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="smlp_PartnersCapitalAccountUnitsIssuedForWarrantExercises" abstract="false" name="PartnersCapitalAccountUnitsIssuedForWarrantExercises" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="smlp_SeriesAPreferredUnitsMember" abstract="true" name="SeriesAPreferredUnitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="smlp_PreferredUnitExchangeOffer" abstract="false" name="PreferredUnitExchangeOffer" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="smlp_PreferredUnitAndStockCorporateReorganization" abstract="false" name="PreferredUnitAndStockCorporateReorganization" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="smlp_PartnersCapitalIssuanceCosts" abstract="false" name="PartnersCapitalIssuanceCosts" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="smlp_IncrementalCommonSharesAttributableToDilutiveEffectOfConversionAndEliminationOfNoncontrollingInterestNetIncome" abstract="false" name="IncrementalCommonSharesAttributableToDilutiveEffectOfConversionAndEliminationOfNoncontrollingInterestNetIncome" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="smlp_SeniorNotesDueAprilTwentyTwentyFiveMember" abstract="true" name="SeniorNotesDueAprilTwentyTwentyFiveMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="smlp_PhantomShareUnitsAndAssociatedDistributionEquivalentRightsMember" abstract="true" name="PhantomShareUnitsAndAssociatedDistributionEquivalentRightsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="smlp_LongTermIncentivePlanMember" abstract="true" name="LongTermIncentivePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="smlp_SMCLongTermIncentivePlanMember" abstract="true" name="SMCLongTermIncentivePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="smlp_ShareBasedCompensationArrangementByShareBasedPaymentAwardGrantDateFairValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardGrantDateFairValue" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="smlp_NumberOfDirectors" abstract="false" name="NumberOfDirectors" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="smlp_ShareBasedCompensationArrangementByShareBasedPaymentAwardVestedAwardAssumedPayoutPercentage" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardVestedAwardAssumedPayoutPercentage" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="smlp_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseLimitationOnExecutiveCompensationAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationNondeductibleExpenseLimitationOnExecutiveCompensationAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="smlp_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseLimitationOnExecutiveCompensationPercent" abstract="false" name="EffectiveIncomeTaxRateReconciliationNondeductibleExpenseLimitationOnExecutiveCompensationPercent" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="smlp_EffectiveIncomeTaxRateReconciliationCorporateReorganizationAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationCorporateReorganizationAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="smlp_EffectiveIncomeTaxRateReconciliationTransactionCostsAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationTransactionCostsAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="smlp_EffectiveIncomeTaxRateReconciliationRemovalOfNoncontrollingInterestsAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationRemovalOfNoncontrollingInterestsAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="smlp_EffectiveIncomeTaxRateReconciliationRemovalOfNontaxableIncomeAmount" abstract="false" name="EffectiveIncomeTaxRateReconciliationRemovalOfNontaxableIncomeAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="smlp_OfficeSpaceMember" abstract="true" name="OfficeSpaceMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="smlp_FinanceAndOperatingLeaseRightOfUseAsset" abstract="false" name="FinanceAndOperatingLeaseRightOfUseAsset" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="smlp_LeaseLiabilitiesCurrentAbstract" abstract="true" name="LeaseLiabilitiesCurrentAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="smlp_FinanceAndOperatingLeaseLiabilityCurrent" abstract="false" name="FinanceAndOperatingLeaseLiabilityCurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="smlp_LeaseLiabilitiesNoncurrentAbstract" abstract="true" name="LeaseLiabilitiesNoncurrentAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="smlp_FinanceAndOperatingLeaseLiabilityNoncurrent" abstract="false" name="FinanceAndOperatingLeaseLiabilityNoncurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="smlp_AdjustedEarningsBeforeInterestTaxesDepreciationAndAmortization" abstract="false" name="AdjustedEarningsBeforeInterestTaxesDepreciationAndAmortization" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="smlp_RockiesBSegmentMember" abstract="true" name="RockiesBSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="smlp_RockiesCSegmentMember" abstract="true" name="RockiesCSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="smlp_ReconciliationOfNetIncomeToEBITDAAdditionsAbstract" abstract="true" name="ReconciliationOfNetIncomeToEBITDAAdditionsAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="smlp_CorporateAndOtherExpenses" abstract="false" name="CorporateAndOtherExpenses" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="smlp_AdjustedEarningsBeforeInterestTaxesDepreciationAndAmortizationProportionalEquityMethodInvestmentAdjustment" abstract="false" name="AdjustedEarningsBeforeInterestTaxesDepreciationAndAmortizationProportionalEquityMethodInvestmentAdjustment" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="smlp_AdjustmentsRelatedToCapitalReimbursementActivity" abstract="false" name="AdjustmentsRelatedToCapitalReimbursementActivity" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="smlp_TransactionCostsAndOtherExpenses" abstract="false" name="TransactionCostsAndOtherExpenses" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="smlp_NewPermianTransmissionFacilityInitialTermLoanMember" abstract="true" name="NewPermianTransmissionFacilityInitialTermLoanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="smlp_NewPermianTransmissionFacilityDelayedDrawCommitmentsMember" abstract="true" name="NewPermianTransmissionFacilityDelayedDrawCommitmentsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="smlp_NewPermianTransmissionFacilityUncommittedIncrementalFacilityMember" abstract="true" name="NewPermianTransmissionFacilityUncommittedIncrementalFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="smlp_EnergyTransferAgreementFirmCapacity" abstract="false" name="EnergyTransferAgreementFirmCapacity" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:volumeItemType"/>
  <xs:element id="smlp_EnergyTransferAgreementTerm" abstract="false" name="EnergyTransferAgreementTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
</xs:schema>
