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  <xs:element id="pagp_InventoryVolumesNoncurrent" abstract="false" name="InventoryVolumesNoncurrent" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="num:volumeItemType"/>
  <xs:element id="pagp_EquityMethodInvestmentOwnershipPercentageAcquired" abstract="false" name="EquityMethodInvestmentOwnershipPercentageAcquired" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="pagp_InitialMargin" abstract="false" name="InitialMargin" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_ForeignExchangeForwardContractsThatExchangeCanadianDollarsForUSDollarsAtAverageRateDisclosedMaturingIn2021Member" abstract="true" name="ForeignExchangeForwardContractsThatExchangeCanadianDollarsForUSDollarsAtAverageRateDisclosedMaturingIn2021Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_GrossMargin" abstract="false" name="GrossMargin" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_NetLongPositionOnCrudeOilDerivativeContractsMember" abstract="true" name="NetLongPositionOnCrudeOilDerivativeContractsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_VariationMarginPostedReturned" abstract="false" name="VariationMarginPostedReturned" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_ContractwithCustomerLiabilityAdditions" abstract="false" name="ContractwithCustomerLiabilityAdditions" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_LeasesFutureMinimumPaymentsDueInFourYears" abstract="false" name="LeasesFutureMinimumPaymentsDueInFourYears" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_Line901IncidentMember" abstract="true" name="Line901IncidentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_NetProceedsFromRepaymentsOfHedgedInventoryFacility" abstract="false" name="NetProceedsFromRepaymentsOfHedgedInventoryFacility" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_LongPositionOnFuelGasRequirementsContractsMember" abstract="true" name="LongPositionOnFuelGasRequirementsContractsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_WinktoWebsterPipelineLLCMember" abstract="true" name="WinktoWebsterPipelineLLCMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_GainOnImpairmentOfInvestmentsInUnconsolidatedEntitiesNet" abstract="false" name="GainOnImpairmentOfInvestmentsInUnconsolidatedEntitiesNet" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_PlainsAllAmericanPNGSuccessorLongTermIncentivePlanMember" abstract="true" name="PlainsAllAmericanPNGSuccessorLongTermIncentivePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_ShortPropanePositionContractsRelatedToSubsequentSaleOfProductMember" abstract="true" name="ShortPropanePositionContractsRelatedToSubsequentSaleOfProductMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_ClassActionLawsuitsMember" abstract="true" name="ClassActionLawsuitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_CapitalContributionsToEquityMethodInvesteesExcludingCapitalizedInterest" abstract="false" name="CapitalContributionsToEquityMethodInvesteesExcludingCapitalizedInterest" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_OxyMember" abstract="true" name="OxyMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_CrudeOilTerminalMember" abstract="true" name="CrudeOilTerminalMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_DiamondPipelineLlcMember" abstract="true" name="DiamondPipelineLlcMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_LimitedPartnersCapitalAccountSharesIssuedRedeemedinRedemptionRightExercises" abstract="false" name="LimitedPartnersCapitalAccountSharesIssuedRedeemedinRedemptionRightExercises" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="pagp_SegmentAdjustedEBITDA" abstract="false" name="SegmentAdjustedEBITDA" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_ShortButanePositionContractsRelatedToSubsequentSaleOfProductMember" abstract="true" name="ShortButanePositionContractsRelatedToSubsequentSaleOfProductMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_MidlandTexasToWebsterTexasPipelineSegmentMember" abstract="true" name="MidlandTexasToWebsterTexasPipelineSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_PartnersCapitalNoteAbstract" abstract="true" name="PartnersCapitalNoteAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="pagp_ConsentDecreeCompensationForInjuriesToDestructionOfLossOfUseOfNaturalResourcesMember" abstract="true" name="ConsentDecreeCompensationForInjuriesToDestructionOfLossOfUseOfNaturalResourcesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_OtherEquityMethodInvestmentMember" abstract="true" name="OtherEquityMethodInvestmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_ConsolidatedFinanceSubsidiaryIssuerMember" abstract="true" name="ConsolidatedFinanceSubsidiaryIssuerMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_ContractWithCustomerAssetAndLiabilityTable" abstract="true" name="ContractWithCustomerAssetAndLiabilityTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="pagp_TradeAccountsReceivableAndOtherReceivablesNetMember" abstract="true" name="TradeAccountsReceivableAndOtherReceivablesNetMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_CrudeOilNGLAndOtherTerminallingAndStorageMember" abstract="true" name="CrudeOilNGLAndOtherTerminallingAndStorageMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_TruckingEquipmentAndOtherMember" abstract="true" name="TruckingEquipmentAndOtherMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_OtherInventoryMember" abstract="true" name="OtherInventoryMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_LenderTypeAxis" abstract="true" name="LenderTypeAxis" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:dimensionItem" type="xbrli:stringItemType"/>
  <xs:element id="pagp_LenderTypeDomain" abstract="true" name="LenderTypeDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_ExchangeOfAapUnitsAndClassBSharesForClassaSharesMember" abstract="true" name="ExchangeOfAapUnitsAndClassBSharesForClassaSharesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_TermLoanMember" abstract="true" name="TermLoanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_SharesClassAMember" abstract="true" name="SharesClassAMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_STACKPipelineLLCMember" abstract="true" name="STACKPipelineLLCMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_LeasesFutureMinimumPaymentsDueInThreeYear" abstract="false" name="LeasesFutureMinimumPaymentsDueInThreeYear" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_TariffActivitiesCrudeOilPipelinesMember" abstract="true" name="TariffActivitiesCrudeOilPipelinesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_EightForwardStartingThirtyYearInterestRateSwaps073PercentMember" abstract="true" name="EightForwardStartingThirtyYearInterestRateSwaps073PercentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_FMGatheringLLCMember" abstract="true" name="FMGatheringLLCMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_ScheduleOfInventoryLinefillAndBaseGasAndLongTermInventoryTableTextBlock" abstract="false" name="ScheduleOfInventoryLinefillAndBaseGasAndLongTermInventoryTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType"/>
  <xs:element id="pagp_LongTermInventoryCostingAdjustments" abstract="false" name="LongTermInventoryCostingAdjustments" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_RedOakPiplelineLLCMember" abstract="true" name="RedOakPiplelineLLCMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_PlainsAllAmericanLongTermIncentivePlansMember" abstract="true" name="PlainsAllAmericanLongTermIncentivePlansMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_AccumulatedAmortizationOfOtherAssetsMiscellaneousNoncurrent" abstract="false" name="AccumulatedAmortizationOfOtherAssetsMiscellaneousNoncurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_EnterpriseProductsPartnersLPMember" abstract="true" name="EnterpriseProductsPartnersLPMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_EquityIndexedCompensationExpenseAwardsThatWillOrMayBeSettledInUnits" abstract="false" name="EquityIndexedCompensationExpenseAwardsThatWillOrMayBeSettledInUnits" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_LeasesFutureMinimumPaymentsDueInTwoYears" abstract="false" name="LeasesFutureMinimumPaymentsDueInTwoYears" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_SeniorSecuredHedgedInventoryFacilityMember" abstract="true" name="SeniorSecuredHedgedInventoryFacilityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_ContractwithCustomerLiabilityOther" abstract="false" name="ContractwithCustomerLiabilityOther" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_TruckingMember" abstract="true" name="TruckingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_NonextendingLenderMember" abstract="true" name="NonextendingLenderMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_WhiteCliffsPipelineLlcMember" abstract="true" name="WhiteCliffsPipelineLlcMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_ComputationOfBasicAndDilutedEarningsPerLimitedPartnerUnitTable" abstract="true" name="ComputationOfBasicAndDilutedEarningsPerLimitedPartnerUnitTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="pagp_SeniorNotesPublicOfferingPrice" abstract="false" name="SeniorNotesPublicOfferingPrice" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="pagp_LeasesRightOfUseAsset" abstract="false" name="LeasesRightOfUseAsset" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_IndictmentNumberofMisdemeanorChargesNotGuiltyVerdictStrictLiabilityAnimalTakingsCount" abstract="false" name="IndictmentNumberofMisdemeanorChargesNotGuiltyVerdictStrictLiabilityAnimalTakingsCount" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="pagp_LimitedPartnersCapitalAccountSharesIssuedFromConversion" abstract="false" name="LimitedPartnersCapitalAccountSharesIssuedFromConversion" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="pagp_GOZoneTermLoan2Member" abstract="true" name="GOZoneTermLoan2Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_SubsidiaryOfLimitedLiabilityCompanyOrLimitedPartnershipOwnershipInterestUnits" abstract="false" name="SubsidiaryOfLimitedLiabilityCompanyOrLimitedPartnershipOwnershipInterestUnits" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="pagp_PartnersCapitalAndDistributionLineItems" abstract="true" name="PartnersCapitalAndDistributionLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="pagp_DelekLogisticsPartnersLPMember" abstract="true" name="DelekLogisticsPartnersLPMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_NumberOfDaysRequiredForDistributionToUnitholdersAfterEndOfQuarter" abstract="false" name="NumberOfDaysRequiredForDistributionToUnitholdersAfterEndOfQuarter" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="pagp_TariffActivitiesNGLPipelinesMember" abstract="true" name="TariffActivitiesNGLPipelinesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_IndictmentNumberofMisdemeanorChargesGuiltyVerdictStrictLiabilityAnimalTakingsCount" abstract="false" name="IndictmentNumberofMisdemeanorChargesGuiltyVerdictStrictLiabilityAnimalTakingsCount" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="pagp_AAPUnitsMember" abstract="true" name="AAPUnitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_GoodwillAccumulatedImpairmentForeignCurrencyTranslationGainLoss" abstract="false" name="GoodwillAccumulatedImpairmentForeignCurrencyTranslationGainLoss" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_InventoryWeightedAveragePricePerUnitCurrent" abstract="false" name="InventoryWeightedAveragePricePerUnitCurrent" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="srt-types:perUnitItemType"/>
  <xs:element id="pagp_LeasesWeightedAverageDiscountRatePercentAbstract" abstract="true" name="LeasesWeightedAverageDiscountRatePercentAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="pagp_LesseeLeasesTermOfContract" abstract="false" name="LesseeLeasesTermOfContract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="pagp_StorageTerminalAndRailFacilitiesMember" abstract="true" name="StorageTerminalAndRailFacilitiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_OrganizationConsolidationAndPresentationOfFinancialStatementsTable" abstract="true" name="OrganizationConsolidationAndPresentationOfFinancialStatementsTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="pagp_DebtInstrumentCoverageRatioDebtToEBITDAMaximum" abstract="false" name="DebtInstrumentCoverageRatioDebtToEBITDAMaximum" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="pagp_InvestmentAndAcquisitionCapital" abstract="false" name="InvestmentAndAcquisitionCapital" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_AOCIOtherIncludingPortionAttributabletoNoncontrollingInterestMember" abstract="true" name="AOCIOtherIncludingPortionAttributabletoNoncontrollingInterestMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_SeniorNotesDueInJanuary2043At4.30PercentMember" abstract="true" name="SeniorNotesDueInJanuary2043At4.30PercentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_IndictmentNumberofMisdemeanorChargesGuiltyVerdictReportingCount" abstract="false" name="IndictmentNumberofMisdemeanorChargesGuiltyVerdictReportingCount" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="pagp_NetShortPositionContractsRelatedToAnticipatedNetSalesOfInventoryMember" abstract="true" name="NetShortPositionContractsRelatedToAnticipatedNetSalesOfInventoryMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_LeasesFutureMinimumPaymentsDueInFiveYears" abstract="false" name="LeasesFutureMinimumPaymentsDueInFiveYears" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_SeniorNotesDueInMay2036At6.70PercentMember" abstract="true" name="SeniorNotesDueInMay2036At6.70PercentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_GOZoneTermLoan1Member" abstract="true" name="GOZoneTermLoan1Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_ThirdPartyEnvironmentalRecoveriesReceivedAndReceivable" abstract="false" name="ThirdPartyEnvironmentalRecoveriesReceivedAndReceivable" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_SeniorNotesDueInJune2022At3.65PercentMember" abstract="true" name="SeniorNotesDueInJune2022At3.65PercentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_DebtInstrumentCoverageRatioDebtToEBITDAAcquisitionPeriodMaximum" abstract="false" name="DebtInstrumentCoverageRatioDebtToEBITDAAcquisitionPeriodMaximum" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="pagp_InventoryWriteDownNoncurrent" abstract="false" name="InventoryWriteDownNoncurrent" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_GainsLossesOnAssetSalesAndAssetImpairmentsNetMember" abstract="true" name="GainsLossesOnAssetSalesAndAssetImpairmentsNetMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_AssetsAndLiabilitiesLesseeTableTextBlock" abstract="false" name="AssetsAndLiabilitiesLesseeTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType"/>
  <xs:element id="pagp_LeasesLiability" abstract="false" name="LeasesLiability" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_BridgeTexPipelineCompanyLLCMember" abstract="true" name="BridgeTexPipelineCompanyLLCMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_PartnersCapitalAccountSharesCancellationOfShares" abstract="false" name="PartnersCapitalAccountSharesCancellationOfShares" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="pagp_ThirdPartyMember" abstract="true" name="ThirdPartyMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_InventoryVolumesCurrent" abstract="false" name="InventoryVolumesCurrent" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="num:volumeItemType"/>
  <xs:element id="pagp_ChangeInContractWithCustomerLiabilityRollForward" abstract="true" name="ChangeInContractWithCustomerLiabilityRollForward" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="pagp_SeniorNotesDueInSeptember2030At380PercentMember" abstract="true" name="SeniorNotesDueInSeptember2030At380PercentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_SeniorNotesDueInJune2042At5.15PercentMember" abstract="true" name="SeniorNotesDueInJune2042At5.15PercentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_CounterpartyDeficienciesUnbilledAndUncollected" abstract="false" name="CounterpartyDeficienciesUnbilledAndUncollected" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_ConversionOfAapManagementUnitsIntoAapUnitsMember" abstract="true" name="ConversionOfAapManagementUnitsIntoAapUnitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_OffsettingAssetsLiabilitiesTable" abstract="true" name="OffsettingAssetsLiabilitiesTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="pagp_PartnersCapitalDeferredTaxAsset" abstract="false" name="PartnersCapitalDeferredTaxAsset" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_MarathonPetroleumCorporationMember" abstract="true" name="MarathonPetroleumCorporationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_SegmentTransportationMember" abstract="true" name="SegmentTransportationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_SeniorNotesDueInJanuary2023At2.85PercentMember" abstract="true" name="SeniorNotesDueInJanuary2023At2.85PercentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_MaintenanceCapital" abstract="false" name="MaintenanceCapital" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_LeasesFutureMinimumPaymentsDueThereafter" abstract="false" name="LeasesFutureMinimumPaymentsDueThereafter" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_CanadianTaxAuthoritiesMember" abstract="true" name="CanadianTaxAuthoritiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_PlainsAllAmericanGPLLCMember" abstract="true" name="PlainsAllAmericanGPLLCMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_MinimumVolumeCommitmentAgreementsMember" abstract="true" name="MinimumVolumeCommitmentAgreementsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_FieldOperatingCostsMember" abstract="true" name="FieldOperatingCostsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_FourthQuarterDistributionMember" abstract="true" name="FourthQuarterDistributionMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_ContractWithCustomerCounterpartyDeficienciesTableTextBlock" abstract="false" name="ContractWithCustomerCounterpartyDeficienciesTableTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType"/>
  <xs:element id="pagp_SalesAndRelatedRevenuesMember" abstract="true" name="SalesAndRelatedRevenuesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_InventoryWeightedAveragePricePerUnitNoncurrent" abstract="false" name="InventoryWeightedAveragePricePerUnitNoncurrent" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="srt-types:perUnitItemType"/>
  <xs:element id="pagp_DeferredStateandLocalIncomeTaxExpenseBenefitNetofFederalBenefitExpense" abstract="false" name="DeferredStateandLocalIncomeTaxExpenseBenefitNetofFederalBenefitExpense" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_CounterpartyDeficiencies" abstract="false" name="CounterpartyDeficiencies" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_DeficienciesUnderMinimumVolumeCommitmentsNet" abstract="false" name="DeficienciesUnderMinimumVolumeCommitmentsNet" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_ScheduleOfDebtInstrumentsTable" abstract="true" name="ScheduleOfDebtInstrumentsTable" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrldt:hypercubeItem" type="xbrli:stringItemType"/>
  <xs:element id="pagp_ContractWithCustomerContractualRightsOfOffsetWithCounterparties" abstract="false" name="ContractWithCustomerContractualRightsOfOffsetWithCounterparties" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_RedRiverPipelineCompanyLLCMember" abstract="true" name="RedRiverPipelineCompanyLLCMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_ForeignExchangeForwardContractsThatExchangeUSDollarsForCanadianDollarsAtAverageRateDisclosedMaturingIn2021Member" abstract="true" name="ForeignExchangeForwardContractsThatExchangeUSDollarsForCanadianDollarsAtAverageRateDisclosedMaturingIn2021Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_SeriesAPreferredUnitsMember" abstract="true" name="SeriesAPreferredUnitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_CrudeOilSalesAgreementsEnteredIntoInConjunctionWIthStorageArrangementsAndFutureInventoryExchangesMember" abstract="true" name="CrudeOilSalesAgreementsEnteredIntoInConjunctionWIthStorageArrangementsAndFutureInventoryExchangesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_FieldOperatingCostsAndGeneralAndAdministrativeExpensesPolicyTextBlock" abstract="false" name="FieldOperatingCostsAndGeneralAndAdministrativeExpensesPolicyTextBlock" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType"/>
  <xs:element id="pagp_OtherDebtMember" abstract="true" name="OtherDebtMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_PublicUnitHoldersMember" abstract="true" name="PublicUnitHoldersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_PlainsAapLPMember" abstract="true" name="PlainsAapLPMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_CommonUnitsAndSeriesAPreferredUnitsMember" abstract="true" name="CommonUnitsAndSeriesAPreferredUnitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_SaddlehornPipelineCompanyLlcMember" abstract="true" name="SaddlehornPipelineCompanyLlcMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_LeasesFutureMinimumPaymentsDueInOneYear" abstract="false" name="LeasesFutureMinimumPaymentsDueInOneYear" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_PartnersCapitalUnitsOther" abstract="false" name="PartnersCapitalUnitsOther" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="pagp_SegmentSupplyAndLogisticsMember" abstract="true" name="SegmentSupplyAndLogisticsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_CommonUnitsMember" abstract="true" name="CommonUnitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_SeniorNotesDueInOctober2025At4.65PercentMember" abstract="true" name="SeniorNotesDueInOctober2025At4.65PercentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_PartnersCapitalAccountSharesIncreaseFromSubsidiaryPreferredUnitIssuance" abstract="false" name="PartnersCapitalAccountSharesIncreaseFromSubsidiaryPreferredUnitIssuance" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="pagp_UnitholderDerivativeLawsuitsMember" abstract="true" name="UnitholderDerivativeLawsuitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_NGLTerminalsMember" abstract="true" name="NGLTerminalsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_CaplinePipelineCompanyLLCMember" abstract="true" name="CaplinePipelineCompanyLLCMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_SeniorNotesDueInFebruary2021At5.00PercentMember" abstract="true" name="SeniorNotesDueInFebruary2021At5.00PercentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_LimitedLiabilityCompanyLLCorLimitedPartnershipLPMembersorLimitedPartnersOwnershipInterestUnits" abstract="false" name="LimitedLiabilityCompanyLLCorLimitedPartnershipLPMembersorLimitedPartnersOwnershipInterestUnits" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="pagp_AAPManagementUnitsMember" abstract="true" name="AAPManagementUnitsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_InventoryWeightedAveragePricePerUnitLinefillAndBaseGas" abstract="false" name="InventoryWeightedAveragePricePerUnitLinefillAndBaseGas" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="srt-types:perUnitItemType"/>
  <xs:element id="pagp_ExxonMobilCorporationMember" abstract="true" name="ExxonMobilCorporationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_LiabilitiesForOutstandingChecks" abstract="false" name="LiabilitiesForOutstandingChecks" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_RailLoadAndUnloadMember" abstract="true" name="RailLoadAndUnloadMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_CactusIIPipelineLLCMember" abstract="true" name="CactusIIPipelineLLCMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_LongTermStorageTerminallingAndThroughputAgreementsRevenuesMember" abstract="true" name="LongTermStorageTerminallingAndThroughputAgreementsRevenuesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_UndividedJointInterestInPipelineSegmentMember" abstract="true" name="UndividedJointInterestInPipelineSegmentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_LeaseWeightedAverageRemainingLeaseTermAbstract" abstract="true" name="LeaseWeightedAverageRemainingLeaseTermAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="pagp_DebtNumberOfInstruments" abstract="false" name="DebtNumberOfInstruments" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="pagp_UsGaap_ProceedsFromSaleOfProductiveAssetsAndAgreements" abstract="false" name="UsGaap_ProceedsFromSaleOfProductiveAssetsAndAgreements" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_SegmentFacilitiesMember" abstract="true" name="SegmentFacilitiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_LongTermDebtWeightedAverageMaturity" abstract="false" name="LongTermDebtWeightedAverageMaturity" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="pagp_TradeAccountsReceivableNetDisclosureOfMaximumAgeOfBalancesPastScheduledInvoiceDate" abstract="false" name="TradeAccountsReceivableNetDisclosureOfMaximumAgeOfBalancesPastScheduledInvoiceDate" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="pagp_SeniorNotesDueInJanuary2020At5.75PercentMember" abstract="true" name="SeniorNotesDueInJanuary2020At5.75PercentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_Phillips66CompanyMember" abstract="true" name="Phillips66CompanyMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_SharesClassBMember" abstract="true" name="SharesClassBMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_PlainsAllAmerican2013LongTermIncentivePlanMember" abstract="true" name="PlainsAllAmerican2013LongTermIncentivePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_EquityMethodInvestmentOwnershipPercentageSold" abstract="false" name="EquityMethodInvestmentOwnershipPercentageSold" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="pagp_LongPowerPositionForPowerSupplyRequirementsContractsMember" abstract="true" name="LongPowerPositionForPowerSupplyRequirementsContractsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_PercentageDistributionOfAvailableCash" abstract="false" name="PercentageDistributionOfAvailableCash" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="pagp_SeniorNotesDueInDecember2029At355PercentMember" abstract="true" name="SeniorNotesDueInDecember2029At355PercentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_LineOfCreditFacilityPeriodForWhichTermOfCreditFacilityMayBeExtended" abstract="false" name="LineOfCreditFacilityPeriodForWhichTermOfCreditFacilityMayBeExtended" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="pagp_SeniorNotesDueInNovember2024At3.60PercentMember" abstract="true" name="SeniorNotesDueInNovember2024At3.60PercentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_SignificantCostsRelatedToLegalAndEnvironmentalRemediationMatters" abstract="false" name="SignificantCostsRelatedToLegalAndEnvironmentalRemediationMatters" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_BasicAndDilutedEarningsPerShareLineItems" abstract="true" name="BasicAndDilutedEarningsPerShareLineItems" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="pagp_InventoryLinefillAndBaseGasAndLongTermInventoryDisclosureAbstract" abstract="true" name="InventoryLinefillAndBaseGasAndLongTermInventoryDisclosureAbstract" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:stringItemType"/>
  <xs:element id="pagp_IndictmentNumberofMisdemeanorChargesGuiltyVerdict" abstract="false" name="IndictmentNumberofMisdemeanorChargesGuiltyVerdict" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="pagp_NetGainLossOnForeignCurrencyRevaluation" abstract="false" name="NetGainLossOnForeignCurrencyRevaluation" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_ProceedsFromContributionsFromNoncontrollingInterests" abstract="false" name="ProceedsFromContributionsFromNoncontrollingInterests" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_DeferredTaxAssetsInvestmentsInSubsidiaries" abstract="false" name="DeferredTaxAssetsInvestmentsInSubsidiaries" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_IntangibleAssetsEstimateOfRiskTheoreticalMarketParticipant" abstract="false" name="IntangibleAssetsEstimateOfRiskTheoreticalMarketParticipant" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="num:percentItemType"/>
  <xs:element id="pagp_IndictmentNumberofMisdemeanorChargesGuiltyVerdictStrictLiabilityDischargeCount" abstract="false" name="IndictmentNumberofMisdemeanorChargesGuiltyVerdictStrictLiabilityDischargeCount" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:integerItemType"/>
  <xs:element id="pagp_PipelineRevenuesSupportedByMinimumVolumeCommitmentsAndLongTermCapacityAgreementsMember" abstract="true" name="PipelineRevenuesSupportedByMinimumVolumeCommitmentsAndLongTermCapacityAgreementsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_AccumulatedAmortizationOfOtherAssetsNoncurrent" abstract="false" name="AccumulatedAmortizationOfOtherAssetsNoncurrent" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_SeniorNotesDueInJanuary2037At6.65PercentMember" abstract="true" name="SeniorNotesDueInJanuary2037At6.65PercentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
  <xs:element id="pagp_DepreciationAndAmortizationOfUnconsolidatedEntities" abstract="false" name="DepreciationAndAmortizationOfUnconsolidatedEntities" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_LinefillAndBaseGas" abstract="false" name="LinefillAndBaseGas" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="pagp_SeniorNotesDueInFebruary2045At4.90PercentMember" abstract="true" name="SeniorNotesDueInFebruary2045At4.90PercentMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="nonnum:domainItemType"/>
</xs:schema>
