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    <ReturnTs>2026-03-20T19:11:55Z</ReturnTs>
    <TaxPeriodEndDt>2025-12-31</TaxPeriodEndDt>
    <ReturnTypeCd>990EZ</ReturnTypeCd>
    <TaxPeriodBeginDt>2025-01-01</TaxPeriodBeginDt>
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      <EIN>820166287</EIN>
      <BusinessName>
        <BusinessNameLine1Txt>SOUTH BOISE WATER COMPANY</BusinessNameLine1Txt>
      </BusinessName>
      <BusinessNameControlTxt>SOUT</BusinessNameControlTxt>
      <PhoneNum>2084478600</PhoneNum>
      <USAddress>
        <AddressLine1Txt>PO BOX 6005</AddressLine1Txt>
        <CityNm>BOISE</CityNm>
        <StateAbbreviationCd>ID</StateAbbreviationCd>
        <ZIPCd>837076005</ZIPCd>
      </USAddress>
    </Filer>
    <BusinessOfficerGrp>
      <PersonNm>Tasha Schreiter</PersonNm>
      <PersonTitleTxt>Treasurer</PersonTitleTxt>
      <PhoneNum>2084478600</PhoneNum>
      <SignatureDt>2026-03-19</SignatureDt>
    </BusinessOfficerGrp>
    <TaxYr>2025</TaxYr>
    <BuildTS>2025-03-06 01:10:19Z</BuildTS>
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      <MethodOfAccountingCashInd>X</MethodOfAccountingCashInd>
      <ScheduleBNotRequiredInd>X</ScheduleBNotRequiredInd>
      <WebsiteAddressTxt>https://southboisewater.org/</WebsiteAddressTxt>
      <Organization501cInd organization501cTypeTxt="12">X</Organization501cInd>
      <TypeOfOrganizationCorpInd>X</TypeOfOrganizationCorpInd>
      <GrossReceiptsAmt>172251</GrossReceiptsAmt>
      <InfoInScheduleOPartIInd>X</InfoInScheduleOPartIInd>
      <MembershipDuesAmt>153144</MembershipDuesAmt>
      <InvestmentIncomeAmt>8803</InvestmentIncomeAmt>
      <OtherRevenueTotalAmt>10304</OtherRevenueTotalAmt>
      <TotalRevenueAmt>172251</TotalRevenueAmt>
      <FeesAndOtherPymtToIndCntrctAmt>87929</FeesAndOtherPymtToIndCntrctAmt>
      <PrintingPublicationsPostageAmt>797</PrintingPublicationsPostageAmt>
      <OtherExpensesTotalAmt>30183</OtherExpensesTotalAmt>
      <TotalExpensesAmt>118909</TotalExpensesAmt>
      <ExcessOrDeficitForYearAmt>53342</ExcessOrDeficitForYearAmt>
      <NetAssetsOrFundBalancesBOYAmt>236992</NetAssetsOrFundBalancesBOYAmt>
      <NetAssetsOrFundBalancesEOYAmt>290334</NetAssetsOrFundBalancesEOYAmt>
      <CashSavingsAndInvestmentsGrp>
        <BOYAmt>236992</BOYAmt>
        <EOYAmt>290334</EOYAmt>
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        <BOYAmt>236992</BOYAmt>
        <EOYAmt>290334</EOYAmt>
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        <BOYAmt>236992</BOYAmt>
        <EOYAmt>290334</EOYAmt>
      </NetAssetsOrFundBalancesGrp>
      <PrimaryExemptPurposeTxt>Exempt purpose: To deliver water to its shareholders for the purposes of irrigation, aesthetics, fish and wildflife, manufacturing, power and mitigation; and will seek and protect all water and storage rights to which it is entitled.</PrimaryExemptPurposeTxt>
      <ProgramSrvcAccomplishmentGrp>
        <DescriptionProgramSrvcAccomTxt>Deliver water for irrigation, aesthetics, fish and wildflife, manufacturing, power and mitigation, and to protect all water and storage rights.</DescriptionProgramSrvcAccomTxt>
        <ProgramServiceExpensesAmt>118909</ProgramServiceExpensesAmt>
      </ProgramSrvcAccomplishmentGrp>
      <TotalProgramServiceExpensesAmt>118909</TotalProgramServiceExpensesAmt>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm referenceDocumentName="CompensationExplanation">Doug Zamzow</PersonNm>
        <TitleTxt>Vice President</TitleTxt>
        <AverageHrsPerWkDevotedToPosRt>8.00</AverageHrsPerWkDevotedToPosRt>
        <CompensationAmt>0</CompensationAmt>
        <EmployeeBenefitProgramAmt>0</EmployeeBenefitProgramAmt>
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      </OfficerDirectorTrusteeEmplGrp>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm referenceDocumentName="CompensationExplanation">Thomas Eschen</PersonNm>
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        <CompensationAmt>0</CompensationAmt>
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      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm referenceDocumentName="CompensationExplanation">Tasha Schreiter</PersonNm>
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        <CompensationAmt>5232</CompensationAmt>
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      </OfficerDirectorTrusteeEmplGrp>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm referenceDocumentName="CompensationExplanation">Mike Harrison</PersonNm>
        <TitleTxt>Watermaster / Secretary</TitleTxt>
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        <CompensationAmt>61289</CompensationAmt>
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      </OfficerDirectorTrusteeEmplGrp>
      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm referenceDocumentName="CompensationExplanation">Ken Mallea</PersonNm>
        <TitleTxt>President</TitleTxt>
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      <OfficerDirectorTrusteeEmplGrp>
        <PersonNm referenceDocumentName="CompensationExplanation">Richard Stewart</PersonNm>
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      <OfficerDirectorTrusteeEmplGrp>
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        <PersonNm>Tasha Schreiter</PersonNm>
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          <AddressLine1Txt>PO Box 6005</AddressLine1Txt>
          <CityNm>Boise</CityNm>
          <StateAbbreviationCd>ID</StateAbbreviationCd>
          <ZIPCd>83707</ZIPCd>
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        <PhoneNum>2084478600</PhoneNum>
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      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Part I, Line 8</FormAndLineReferenceDesc>
        <ExplanationTxt>2024 water rental pool</ExplanationTxt>
      </SupplementalInformationDetail>
      <SupplementalInformationDetail>
        <FormAndLineReferenceDesc>Part I, Line 16</FormAndLineReferenceDesc>
        <ExplanationTxt>Administrative costs: 2420; Ditch maintenance/operational expenses: 12699; Insurance: 8443; Water expenses: 6621</ExplanationTxt>
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