-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
 MFgwCgYEVQgBAQICAf8DSgAwRwJAW2sNKK9AVtBzYZmr6aGjlWyK3XmZv3dTINen
 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 QLvmj7IoQcuOVtHXCo/wC038yF+mfyaoWhILgyEj+/yp++3iGHkz3kmXnrDLACh0
 SU6auU3JKDbyGrIaFLy91Q==

<SEC-DOCUMENT>0001179110-05-017907.txt : 20050913
<SEC-HEADER>0001179110-05-017907.hdr.sgml : 20050913
<ACCEPTANCE-DATETIME>20050913165247
ACCESSION NUMBER:		0001179110-05-017907
CONFORMED SUBMISSION TYPE:	3
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20050912
FILED AS OF DATE:		20050913
DATE AS OF CHANGE:		20050913

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Mann James E
		CENTRAL INDEX KEY:			0001337620

	FILING VALUES:
		FORM TYPE:		3
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-08176
		FILM NUMBER:		051082660

	BUSINESS ADDRESS:	
		BUSINESS PHONE:		(213) 929-1800

	MAIL ADDRESS:	
		STREET 1:		624 S. GRAND AVENUE, STE. 2900
		CITY:			LOS ANGELES
		STATE:			CA
		ZIP:			90277

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:		ONE WILSHIRE BUILDING
		STREET 2:		624 SOUTH GRAND AVENUE, SUITE 2900
		CITY:			LOS ANGELES
		STATE:			CA
		ZIP:			90017-3782
		BUSINESS PHONE:		213 929 1800

	MAIL ADDRESS:	
		STREET 1:		ONE WILSHIRE BUILDING
		STREET 2:		624 SOUTH GRAND AVENUE, SUITE 2900
		CITY:			LOS ANGELES
		STATE:			CA
		ZIP:			90017-3782

	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>2005-09-12</periodOfReport>

    <noSecuritiesOwned>1</noSecuritiesOwned>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001337620</rptOwnerCik>
            <rptOwnerName>Mann James E</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>624 S. GRAND AVENUE, STE. 2900</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>LOS ANGELES</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>90017</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>VP, Controller</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable></nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes></footnotes>

    <ownerSignature>
        <signatureName>/s/ James E Mann</signatureName>
        <signatureDate>2005-09-13</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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