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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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 5FkemRbj+LXGzcsf7axraA==

<SEC-DOCUMENT>0001179110-04-017616.txt : 20040903
<SEC-HEADER>0001179110-04-017616.hdr.sgml : 20040903
<ACCEPTANCE-DATETIME>20040903151625
ACCESSION NUMBER:		0001179110-04-017616
CONFORMED SUBMISSION TYPE:	3
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20040903
FILED AS OF DATE:		20040903
DATE AS OF CHANGE:		20040903

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			JONES WILLIAM D /CA/
		CENTRAL INDEX KEY:			0001228380

	FILING VALUES:
		FORM TYPE:		3
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-08176
		FILM NUMBER:		041016777

	BUSINESS ADDRESS:	
		STREET 1:		101 ASH ST M L
		STREET 2:		HQ18
		CITY:			SAN DIEGO
		STATE:			CA
		ZIP:			92101-3017
		BUSINESS PHONE:		6196964644

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			SOUTHWEST WATER CO
		CENTRAL INDEX KEY:			0000092472
		STANDARD INDUSTRIAL CLASSIFICATION:	WATER SUPPLY [4941]
		IRS NUMBER:				951840947
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		225 N BARRANCA AVE
		STREET 2:		STE 200
		CITY:			WEST COVINA
		STATE:			CA
		ZIP:			91791-1605
		BUSINESS PHONE:		6269151551

	MAIL ADDRESS:	
		STREET 1:		225 N BARRANCA AVENUE
		STREET 2:		SUITE 200
		CITY:			WEST COVINA
		STATE:			CA
		ZIP:			91791-1605

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	SUBURBAN WATER SYSTEMS
		DATE OF NAME CHANGE:	19751202
</SEC-HEADER>
<DOCUMENT>
<TYPE>3
<SEQUENCE>1
<FILENAME>edgar.xml
<DESCRIPTION>FORM 3 -
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>3</documentType>

    <periodOfReport>2004-09-03</periodOfReport>

    <noSecuritiesOwned>0</noSecuritiesOwned>

    <issuer>
        <issuerCik>0000092472</issuerCik>
        <issuerName>SOUTHWEST WATER CO</issuerName>
        <issuerTradingSymbol>SWWC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001228380</rptOwnerCik>
            <rptOwnerName>JONES WILLIAM D /CA/</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>2550 FIFTH AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 725</rptOwnerStreet2>
            <rptOwnerCity>SAN DIEGO</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>92103-6624</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Mr. Jones was elected to the Company's Board on September 1, 2004.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>William D. Jones</signatureName>
        <signatureDate>2004-09-03</signatureDate>
    </ownerSignature>
</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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