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  <xsd:element id="wttr_MidconMember" name="MidconMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="wttr_EagleFordMember" name="EagleFordMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="wttr_BakkenMember" name="BakkenMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="wttr_MarcellusUticaMember" name="MarcellusUticaMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="wttr_RockiesMember" name="RockiesMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="wttr_HaynesvilleE.TexasMember" name="HaynesvilleE.TexasMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="wttr_NumberOfRevenueProducingRegions" name="NumberOfRevenueProducingRegions" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="wttr_PercentageOfRevenue" name="PercentageOfRevenue" nillable="true" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="wttr_DilutiveSecuritiesEffectOnBasicEarningsPerSharePerformanceShareUnits" name="DilutiveSecuritiesEffectOnBasicEarningsPerSharePerformanceShareUnits" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <xsd:element id="wttr_NumberOfEquityMethodInvestee" name="NumberOfEquityMethodInvestee" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="wttr_AllowanceForDoubtfulAccountsIncreaseDecreaseBasedOnRevenue" name="AllowanceForDoubtfulAccountsIncreaseDecreaseBasedOnRevenue" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <xsd:element id="wttr_DilutiveSecuritiesEffectOnBasicEarningsPerShareRestrictiveStockAwards" name="DilutiveSecuritiesEffectOnBasicEarningsPerShareRestrictiveStockAwards" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" xbrli:balance="credit" />
  <xsd:element id="wttr_EliminationsAndOtherGeographicalRegionsMember" name="EliminationsAndOtherGeographicalRegionsMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="wttr_VotingRightsNumberOfVotesPerShare" name="VotingRightsNumberOfVotesPerShare" nillable="true" type="xbrli:integerItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="wttr_InvestmentInJointVentureOneMember" name="InvestmentInJointVentureOneMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="wttr_InvestmentInJointVentureTwoMember" name="InvestmentInJointVentureTwoMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="wttr_IntangibleAssetsIndefiniteLivedExcludingGoodwillNet" name="IntangibleAssetsIndefiniteLivedExcludingGoodwillNet" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="debit" />
  <xsd:element id="wttr_IndefiniteLivedIntangibleAssetWeightedAveragePeriodRenewalTerm" name="IndefiniteLivedIntangibleAssetWeightedAveragePeriodRenewalTerm" nillable="true" type="xbrli:durationItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="wttr_SeveranceCostsPolicyTextBlock" name="SeveranceCostsPolicyTextBlock" nillable="true" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" xbrli:periodType="duration" />
  <xsd:element id="wttr_InvestmentInJointVentureThreeMember" name="InvestmentInJointVentureThreeMember" nillable="true" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" xbrli:periodType="duration" />
  <xsd:element id="wttr_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesAssetRetirementObligation" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedNoncurrentLiabilitiesAssetRetirementObligation" nillable="true" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" xbrli:periodType="instant" xbrli:balance="credit" />
  <xsd:element name="TargetPerformanceUnitsThatCanBeEarned" id="wttr_TargetPerformanceUnitsThatCanBeEarned" type="xbrli:pureItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="RelatedPartiesMember" id="wttr_RelatedPartiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="AssetAcquisitionMember" id="wttr_AssetAcquisitionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="DividendDistributionReductionInAccruedExpensesAndOtherCurrentLiabilities" id="wttr_DividendDistributionReductionInAccruedExpensesAndOtherCurrentLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="ReductionOfAdditionalPaidInCapital" id="wttr_ReductionOfAdditionalPaidInCapital" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="RecyclingFacilitiesMember" id="wttr_RecyclingFacilitiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="AssetAcquisitionRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetRetirementObligationsAndOtherLiabilities" id="wttr_AssetAcquisitionRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedAssetRetirementObligationsAndOtherLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="TaxReceivableAgreementsLiabilitiesNoncurrent" id="wttr_TaxReceivableAgreementsLiabilitiesNoncurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="TaxReceivableAgreementsLiabilities" id="wttr_TaxReceivableAgreementsLiabilities" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="StockIssuedDuringPeriodSharesPerformanceSharesAwardVested" id="wttr_StockIssuedDuringPeriodSharesPerformanceSharesAwardVested" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="StockIssuedDuringPeriodValuePerformanceSharesAwardVested" id="wttr_StockIssuedDuringPeriodValuePerformanceSharesAwardVested" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAddedByPerformanceFactorInPeriod" id="wttr_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsAddedByPerformanceFactorInPeriod" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ScheduleOfBusinessCombinationAndAssetAcquisitionTableTextBlock" id="wttr_ScheduleOfBusinessCombinationAndAssetAcquisitionTableTextBlock" type="dtr-types:textBlockItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="PaymentToAcquireBusinessGrossAndProductiveAssets" id="wttr_PaymentToAcquireBusinessGrossAndProductiveAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="BusinessCombinationAndAssetAcquisitionConsiderationTransferred" id="wttr_BusinessCombinationAndAssetAcquisitionConsiderationTransferred" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="TotalAcquisitionsMember" id="wttr_TotalAcquisitionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="InventoryAndConsumablesMember" id="wttr_InventoryAndConsumablesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="CostOfGoodsAndServicesSoldDepreciationAmortizationAccretionTotal" id="wttr_CostOfGoodsAndServicesSoldDepreciationAmortizationAccretionTotal" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="PermianBasinHaynesvilleAndBakkenMember" id="wttr_PermianBasinHaynesvilleAndBakkenMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="WeightedAverageRemainingAmortizationPeriod" id="wttr_WeightedAverageRemainingAmortizationPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="EquityIncentive2024PlanMember" id="wttr_EquityIncentive2024PlanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="AssetAcquisitionsNumberOfTransaction" id="wttr_AssetAcquisitionsNumberOfTransaction" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentFairValueAllocatedToNetAssets" id="wttr_BusinessCombinationProvisionalInformationInitialAccountingIncompleteAdjustmentFairValueAllocatedToNetAssets" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="FiniteLivedIntangibleAssetExpectedAmortizationAfterYearFour" id="wttr_FiniteLivedIntangibleAssetExpectedAmortizationAfterYearFour" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="DilutiveSecuritiesEffectOnBasicEarningsPerShareStockOptions" id="wttr_DilutiveSecuritiesEffectOnBasicEarningsPerShareStockOptions" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="SesHoldingsLlcMember" id="wttr_SesHoldingsLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="PaymentsForTaxReceivableAgreements" id="wttr_PaymentsForTaxReceivableAgreements" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="EarningsBeforeInterestTaxesDepreciationAndAmortization" id="wttr_EarningsBeforeInterestTaxesDepreciationAndAmortization" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="EightSmallerAssetAcquisitionsMember" id="wttr_EightSmallerAssetAcquisitionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="StockIssuedDuringPeriodValueStockOptionsExercisedCashless" id="wttr_StockIssuedDuringPeriodValueStockOptionsExercisedCashless" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodCashless" id="wttr_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsExercisesInPeriodCashless" type="xbrli:sharesItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="TermLoanFacilityMember" id="wttr_TermLoanFacilityMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="LineOfCreditFacilityContingentIncreaseAdditionalBorrowingCapacity" id="wttr_LineOfCreditFacilityContingentIncreaseAdditionalBorrowingCapacity" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="JohnD.SchmitzMember" id="wttr_JohnD.SchmitzMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="FirstFourYearsMember" id="wttr_FirstFourYearsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="EligibleInvestmentGradeBilledReceivablesMember" id="wttr_EligibleInvestmentGradeBilledReceivablesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="LineOfCreditFacilityBorrowingBase" id="wttr_LineOfCreditFacilityBorrowingBase" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="NetBookValueOfAllMEMember" id="wttr_NetBookValueOfAllMEMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="NolvIpOfTermAdvanceCollateralMember" id="wttr_NolvIpOfTermAdvanceCollateralMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="LineOfCreditFacilityBorrowingLimitPercentage" id="wttr_LineOfCreditFacilityBorrowingLimitPercentage" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="LineOfCreditFacilityBorrowingLimit" id="wttr_LineOfCreditFacilityBorrowingLimit" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="LineOfCreditFacilityLookBackPeriodRedeterminationBeginning" id="wttr_LineOfCreditFacilityLookBackPeriodRedeterminationBeginning" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="LineOfCreditFacilityLookBackPeriodRedeterminationEnding" id="wttr_LineOfCreditFacilityLookBackPeriodRedeterminationEnding" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="DebtInstrumentFloorRate" id="wttr_DebtInstrumentFloorRate" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="LeverageRatio" id="wttr_LeverageRatio" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="CollateralBorrowingBasePercentOne" id="wttr_CollateralBorrowingBasePercentOne" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="CollateralBorrowingBasePercentTwo" id="wttr_CollateralBorrowingBasePercentTwo" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="BorrowingBaseMember" id="wttr_BorrowingBaseMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="AvFarmsLpMember" id="wttr_AvFarmsLpMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SelectWaterReuseLlcMember" id="wttr_SelectWaterReuseLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="GenesesWaterL.p.Member" id="wttr_GenesesWaterL.p.Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="CAndRolloverCompanyLlcMember" id="wttr_CAndRolloverCompanyLlcMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="AvFarmsManagementLlcGeneralPartnerMember" id="wttr_AvFarmsManagementLlcGeneralPartnerMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="InvestmentInJointVentureFourMember" id="wttr_InvestmentInJointVentureFourMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="PerformanceSharesBasedOnFreeCashFlowMember" id="wttr_PerformanceSharesBasedOnFreeCashFlowMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="OldSustainabilityLinkedCreditFacilityMember" id="wttr_OldSustainabilityLinkedCreditFacilityMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="UnamortizedDebtIssuanceCostsTransferred" id="wttr_UnamortizedDebtIssuanceCostsTransferred" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="PerformanceSharesBasedOnReturnOnAssetPerformanceMember" id="wttr_PerformanceSharesBasedOnReturnOnAssetPerformanceMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="PercentageOfTargetAmountEarnedWhenAbsoluteTotalShareholderReturnBetweenZeroPercentAndFifteenPercent" id="wttr_PercentageOfTargetAmountEarnedWhenAbsoluteTotalShareholderReturnBetweenZeroPercentAndFifteenPercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="PercentageOfTargetAmountEarnedWhenAbsoluteTotalShareholderReturnGreaterThanFifteenPercent" id="wttr_PercentageOfTargetAmountEarnedWhenAbsoluteTotalShareholderReturnGreaterThanFifteenPercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="PercentageOfTargetAmountEarnedWhenAbsoluteTotalShareholderReturnLessThanZeroPercent" id="wttr_PercentageOfTargetAmountEarnedWhenAbsoluteTotalShareholderReturnLessThanZeroPercent" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="RelativeTotalShareholderReturnIsGreaterThanOrEqualToEightyPercentAtMaximumMember" id="wttr_RelativeTotalShareholderReturnIsGreaterThanOrEqualToEightyPercentAtMaximumMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="RelativeTotalShareholderReturnIsFiftyFivePercentAtTargetMember" id="wttr_RelativeTotalShareholderReturnIsFiftyFivePercentAtTargetMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="RelativeTotalShareholderReturnIsTwentyFivePercentAtThresholdMember" id="wttr_RelativeTotalShareholderReturnIsTwentyFivePercentAtThresholdMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="RelativeTotalShareholderReturnIsLessThanTwentyFivePercentAtBelowThresholdMember" id="wttr_RelativeTotalShareholderReturnIsLessThanTwentyFivePercentAtBelowThresholdMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="OneSmallerAssetAcquisitionMember" id="wttr_OneSmallerAssetAcquisitionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="PercentageOfOutstandingOptions" id="wttr_PercentageOfOutstandingOptions" type="dtr-types:percentItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="OmniEnvironmentalSolutionsMember" id="wttr_OmniEnvironmentalSolutionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="BusinessCombinationNumberOfSaltWaterDisposalFacilitiesAcquired" id="wttr_BusinessCombinationNumberOfSaltWaterDisposalFacilitiesAcquired" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="BusinessCombinationSaltWaterDisposalFacilityPermittedDisposalCapacityPerDay" id="wttr_BusinessCombinationSaltWaterDisposalFacilityPermittedDisposalCapacityPerDay" type="dtr-types:volumeItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="BusinessCombinationCommercialOilStorageTankFarmCapacityAcquired" id="wttr_BusinessCombinationCommercialOilStorageTankFarmCapacityAcquired" type="dtr-types:volumeItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" />
  <xsd:element name="BusinessCombinationNumberOfSaltWaterDisposalFacilitiesTransferredAsPartOfAcquisition" id="wttr_BusinessCombinationNumberOfSaltWaterDisposalFacilitiesTransferredAsPartOfAcquisition" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="BusinessCombinationNumberOfFluidsHaulingEmployeesTransferred" id="wttr_BusinessCombinationNumberOfFluidsHaulingEmployeesTransferred" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="BusinessCombinationRemainingOfftakeCapacityOfSolidsWasteLandfill" id="wttr_BusinessCombinationRemainingOfftakeCapacityOfSolidsWasteLandfill" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="DistributionsToNoncontrollingInterestHolders" id="wttr_DistributionsToNoncontrollingInterestHolders" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="PaymentsToAcquireBusinessesBaseConsideration" id="wttr_PaymentsToAcquireBusinessesBaseConsideration" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="PaymentsToAcquireBusinessesConsiderationForRetainedNetWorkingCapital" id="wttr_PaymentsToAcquireBusinessesConsiderationForRetainedNetWorkingCapital" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="TotalSegmentsMember" id="wttr_TotalSegmentsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="RemeasurementGainLossOnPropertyPlantAndEquipment" id="wttr_RemeasurementGainLossOnPropertyPlantAndEquipment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="SevenSmallerAssetAcquisitionsMember" id="wttr_SevenSmallerAssetAcquisitionsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="OneAssetAcquisitionMember" id="wttr_OneAssetAcquisitionMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="AccruedSeveranceCostsCurrent" id="wttr_AccruedSeveranceCostsCurrent" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="credit" />
  <xsd:element name="BusinessCombinationConsiderationTransferredPropertyPlantAndEquipment" id="wttr_BusinessCombinationConsiderationTransferredPropertyPlantAndEquipment" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="BusinessCombinationConsiderationTransferredAssetsTransferredOrLiabilitiesAssumedOther" id="wttr_BusinessCombinationConsiderationTransferredAssetsTransferredOrLiabilitiesAssumedOther" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="AssetAcquisitionsAreaOfLand" id="wttr_AssetAcquisitionsAreaOfLand" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="BusinessCombinationConsiderationTransferredPropertyPlantAndEquipmentCarryingValue" id="wttr_BusinessCombinationConsiderationTransferredPropertyPlantAndEquipmentCarryingValue" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="credit" />
  <xsd:element name="NyseTexasInc.Member" id="wttr_NyseTexasInc.Member" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SignificantAccountingPoliciesTable" id="wttr_SignificantAccountingPoliciesTable" type="xbrli:stringItemType" substitutionGroup="xbrldt:hypercubeItem" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SignificantAccountingPoliciesLineItems" id="wttr_SignificantAccountingPoliciesLineItems" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="InterCompanyLoanReceivableFromConsolidatedVie" id="wttr_InterCompanyLoanReceivableFromConsolidatedVie" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="InterCompanyReceivableFromConsolidatedVie" id="wttr_InterCompanyReceivableFromConsolidatedVie" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="LeasingArrangementsReceivables" id="wttr_LeasingArrangementsReceivables" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="instant" abstract="false" xbrli:balance="debit" />
  <xsd:element name="PermianBasinMidconAndHaynesvilleMember" id="wttr_PermianBasinMidconAndHaynesvilleMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardPerformanceShareUnitsPeriod" id="wttr_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerformanceShareUnitsPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardPerformanceMeasurementPeriod" id="wttr_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerformanceMeasurementPeriod" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="ChemicalTechnologiesMember" id="wttr_ChemicalTechnologiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOtherWeightedAverageRemainingContractualTerm" id="wttr_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsOtherWeightedAverageRemainingContractualTerm" type="xbrli:durationItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
  <xsd:element name="SecondaryPublicOfferingMember" id="wttr_SecondaryPublicOfferingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="CommonStockOfferingAbstract" id="wttr_CommonStockOfferingAbstract" type="xbrli:stringItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="SecondaryPublicOfferingBaseOfferingMember" id="wttr_SecondaryPublicOfferingBaseOfferingMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="AggregateProceedsFromIssuanceOfCommonStock" id="wttr_AggregateProceedsFromIssuanceOfCommonStock" type="xbrli:monetaryItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" xbrli:balance="debit" />
  <xsd:element name="BlackRiverRanchMember" id="wttr_BlackRiverRanchMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="FreeLandMember" id="wttr_FreeLandMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="FederalGrazingLeaseLandMember" id="wttr_FederalGrazingLeaseLandMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="AgriculturalLoanMember" id="wttr_AgriculturalLoanMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="true" />
  <xsd:element name="AssetAcquisitionsAreaOfWaterRights" id="wttr_AssetAcquisitionsAreaOfWaterRights" type="xbrli:integerItemType" substitutionGroup="xbrli:item" nillable="true" xbrli:periodType="duration" abstract="false" />
</xsd:schema>
