<?xml version="1.0" encoding="UTF-8"?>

<!--XBRL Document Created with the Workiva Platform-->
<!--Copyright 2026 Workiva-->
<!--r:019f1e26-4d9f-71d1-9e24-5c48d4b46b08,g:70e154e1-41dd-46ab-a25f-29c06cd561c5-->
<link:linkbase xmlns:link="http://www.xbrl.org/2003/linkbase" xmlns:xlink="http://www.w3.org/1999/xlink" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://www.xbrl.org/2003/linkbase http://www.xbrl.org/2003/xbrl-linkbase-2003-12-31.xsd">
  <link:roleRef roleURI="http://www.energyrecovery.com/role/Cover" xlink:type="simple" xlink:href="erii-20260713.xsd#Cover"/>
  <link:presentationLink xlink:role="http://www.energyrecovery.com/role/Cover" xlink:type="extended">
    <link:loc xlink:type="locator" xlink:label="loc_dei_CoverAbstract_019f1e26-4d9f-7368-aa09-46dfec431762" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_CoverAbstract"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentType_019f1e26-4d9f-7e36-a46c-dd8c51d16900" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_DocumentType"/>
    <link:presentationArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019f1e26-4d9f-7368-aa09-46dfec431762" xlink:to="loc_dei_DocumentType_019f1e26-4d9f-7e36-a46c-dd8c51d16900" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_DocumentPeriodEndDate_019f1e26-4d9f-7f08-ab1b-92bea0863197" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_DocumentPeriodEndDate"/>
    <link:presentationArc order="2" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019f1e26-4d9f-7368-aa09-46dfec431762" xlink:to="loc_dei_DocumentPeriodEndDate_019f1e26-4d9f-7f08-ab1b-92bea0863197" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityIncorporationStateCountryCode_019f1e26-4d9f-7826-9544-ef2dbead11fa" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityIncorporationStateCountryCode"/>
    <link:presentationArc order="3" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019f1e26-4d9f-7368-aa09-46dfec431762" xlink:to="loc_dei_EntityIncorporationStateCountryCode_019f1e26-4d9f-7826-9544-ef2dbead11fa" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityFileNumber_019f1e26-4d9f-726e-95ce-a32acac4d67f" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityFileNumber"/>
    <link:presentationArc order="4" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019f1e26-4d9f-7368-aa09-46dfec431762" xlink:to="loc_dei_EntityFileNumber_019f1e26-4d9f-726e-95ce-a32acac4d67f" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityTaxIdentificationNumber_019f1e26-4d9f-7bde-8203-895e1af491a1" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityTaxIdentificationNumber"/>
    <link:presentationArc order="5" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019f1e26-4d9f-7368-aa09-46dfec431762" xlink:to="loc_dei_EntityTaxIdentificationNumber_019f1e26-4d9f-7bde-8203-895e1af491a1" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressAddressLine1_019f1e26-4d9f-7fb7-9d1c-115da44bdc91" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityAddressAddressLine1"/>
    <link:presentationArc order="6" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019f1e26-4d9f-7368-aa09-46dfec431762" xlink:to="loc_dei_EntityAddressAddressLine1_019f1e26-4d9f-7fb7-9d1c-115da44bdc91" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressCityOrTown_019f1e26-4d9f-7f28-9b82-da6fd48cd874" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityAddressCityOrTown"/>
    <link:presentationArc order="7" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019f1e26-4d9f-7368-aa09-46dfec431762" xlink:to="loc_dei_EntityAddressCityOrTown_019f1e26-4d9f-7f28-9b82-da6fd48cd874" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressStateOrProvince_019f1e26-4d9f-739b-9a67-9dd11117a87f" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityAddressStateOrProvince"/>
    <link:presentationArc order="8" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019f1e26-4d9f-7368-aa09-46dfec431762" xlink:to="loc_dei_EntityAddressStateOrProvince_019f1e26-4d9f-739b-9a67-9dd11117a87f" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityAddressPostalZipCode_019f1e26-4d9f-7e99-85ee-6de27b923dca" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityAddressPostalZipCode"/>
    <link:presentationArc order="9" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019f1e26-4d9f-7368-aa09-46dfec431762" xlink:to="loc_dei_EntityAddressPostalZipCode_019f1e26-4d9f-7e99-85ee-6de27b923dca" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_CityAreaCode_019f1e26-4d9f-79fe-8e81-81dc93ade792" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_CityAreaCode"/>
    <link:presentationArc order="10" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019f1e26-4d9f-7368-aa09-46dfec431762" xlink:to="loc_dei_CityAreaCode_019f1e26-4d9f-79fe-8e81-81dc93ade792" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_LocalPhoneNumber_019f1e26-4d9f-7a5b-8287-2487141ed986" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_LocalPhoneNumber"/>
    <link:presentationArc order="11" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019f1e26-4d9f-7368-aa09-46dfec431762" xlink:to="loc_dei_LocalPhoneNumber_019f1e26-4d9f-7a5b-8287-2487141ed986" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_WrittenCommunications_019f1e26-4d9f-7666-b2a4-5d4e46c46690" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_WrittenCommunications"/>
    <link:presentationArc order="12" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019f1e26-4d9f-7368-aa09-46dfec431762" xlink:to="loc_dei_WrittenCommunications_019f1e26-4d9f-7666-b2a4-5d4e46c46690" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_SolicitingMaterial_019f1e26-4d9f-7e1c-a29f-96fa7147b1e5" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_SolicitingMaterial"/>
    <link:presentationArc order="13" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019f1e26-4d9f-7368-aa09-46dfec431762" xlink:to="loc_dei_SolicitingMaterial_019f1e26-4d9f-7e1c-a29f-96fa7147b1e5" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_PreCommencementTenderOffer_019f1e26-4d9f-7bb6-b091-9f94ba149cde" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_PreCommencementTenderOffer"/>
    <link:presentationArc order="14" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019f1e26-4d9f-7368-aa09-46dfec431762" xlink:to="loc_dei_PreCommencementTenderOffer_019f1e26-4d9f-7bb6-b091-9f94ba149cde" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_PreCommencementIssuerTenderOffer_019f1e26-4d9f-7e9f-86ba-dc8e44d6c7f5" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_PreCommencementIssuerTenderOffer"/>
    <link:presentationArc order="15" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019f1e26-4d9f-7368-aa09-46dfec431762" xlink:to="loc_dei_PreCommencementIssuerTenderOffer_019f1e26-4d9f-7e9f-86ba-dc8e44d6c7f5" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_Security12bTitle_019f1e26-4d9f-7136-8fe7-6be85ce66198" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_Security12bTitle"/>
    <link:presentationArc order="16" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019f1e26-4d9f-7368-aa09-46dfec431762" xlink:to="loc_dei_Security12bTitle_019f1e26-4d9f-7136-8fe7-6be85ce66198" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_TradingSymbol_019f1e26-4d9f-7120-847d-e641b5f54b4d" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_TradingSymbol"/>
    <link:presentationArc order="17" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019f1e26-4d9f-7368-aa09-46dfec431762" xlink:to="loc_dei_TradingSymbol_019f1e26-4d9f-7120-847d-e641b5f54b4d" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_SecurityExchangeName_019f1e26-4d9f-7dc0-b823-22ba9f13159e" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_SecurityExchangeName"/>
    <link:presentationArc order="18" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019f1e26-4d9f-7368-aa09-46dfec431762" xlink:to="loc_dei_SecurityExchangeName_019f1e26-4d9f-7dc0-b823-22ba9f13159e" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityEmergingGrowthCompany_019f1e26-4d9f-7796-bdec-eb5695c8aa6e" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityEmergingGrowthCompany"/>
    <link:presentationArc order="19" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019f1e26-4d9f-7368-aa09-46dfec431762" xlink:to="loc_dei_EntityEmergingGrowthCompany_019f1e26-4d9f-7796-bdec-eb5695c8aa6e" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityCentralIndexKey_019f1e26-4d9f-7867-bd49-af5ad8c24922" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityCentralIndexKey"/>
    <link:presentationArc order="20" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019f1e26-4d9f-7368-aa09-46dfec431762" xlink:to="loc_dei_EntityCentralIndexKey_019f1e26-4d9f-7867-bd49-af5ad8c24922" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_AmendmentFlag_019f1e26-4d9f-733f-af02-5ddbc6e7e225" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_AmendmentFlag"/>
    <link:presentationArc order="21" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019f1e26-4d9f-7368-aa09-46dfec431762" xlink:to="loc_dei_AmendmentFlag_019f1e26-4d9f-733f-af02-5ddbc6e7e225" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
    <link:loc xlink:type="locator" xlink:label="loc_dei_EntityRegistrantName_019f1e26-4d9f-77cf-ab9f-4cbde122ae99" xlink:href="https://xbrl.sec.gov/dei/2024/dei-2024.xsd#dei_EntityRegistrantName"/>
    <link:presentationArc order="22" xlink:arcrole="http://www.xbrl.org/2003/arcrole/parent-child" xlink:from="loc_dei_CoverAbstract_019f1e26-4d9f-7368-aa09-46dfec431762" xlink:to="loc_dei_EntityRegistrantName_019f1e26-4d9f-77cf-ab9f-4cbde122ae99" xlink:type="arc" preferredLabel="http://www.xbrl.org/2003/role/terseLabel"/>
  </link:presentationLink>
</link:linkbase>
