-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
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MIC-Info: RSA-MD5,RSA,
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<SEC-DOCUMENT>0000807249-05-000336.txt : 20051006
<SEC-HEADER>0000807249-05-000336.hdr.sgml : 20051006
<ACCEPTANCE-DATETIME>20051006154048
ACCESSION NUMBER:		0000807249-05-000336
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20051005
FILED AS OF DATE:		20051006
DATE AS OF CHANGE:		20051006

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			WATTS WATER TECHNOLOGIES INC
		CENTRAL INDEX KEY:			0000795403
		STANDARD INDUSTRIAL CLASSIFICATION:	MISCELLANEOUS FABRICATED METAL PRODUCTS [3490]
		IRS NUMBER:				042916536
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0630

	BUSINESS ADDRESS:	
		STREET 1:		815 CHESTNUT ST
		CITY:			NORTH ANDOVER
		STATE:			MA
		ZIP:			01845
		BUSINESS PHONE:		9786881811

	MAIL ADDRESS:	
		STREET 1:		815 CHESTNUT STREET
		CITY:			NORTH ANDOVER
		STATE:			MA
		ZIP:			01845

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	WATTS INDUSTRIES INC
		DATE OF NAME CHANGE:	19920703

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			GABELLI MARIO J
		CENTRAL INDEX KEY:			0001185533

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-11499
		FILM NUMBER:		051127180

	BUSINESS ADDRESS:	
		STREET 1:		C/O GABELLI ASSET MANAGEMENT INC
		STREET 2:		ONE CORPORATE CENTER
		CITY:			RYE
		STATE:			NY
		ZIP:			16580
		BUSINESS PHONE:		9149215017

	MAIL ADDRESS:	
		STREET 1:		C/O GABELLI ASSET MANAGEMENT INC
		STREET 2:		ONE CORPORATE CENTER
		CITY:			RYE
		STATE:			NY
		ZIP:			10580

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			GGCP, INC.
		CENTRAL INDEX KEY:			0001238894
		STATE OF INCORPORATION:			NY
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-11499
		FILM NUMBER:		051127181

	BUSINESS ADDRESS:	
		STREET 1:		ONE CORPORATE CENTER
		CITY:			RYE
		STATE:			NY
		ZIP:			10580
		BUSINESS PHONE:		9149215100

	MAIL ADDRESS:	
		STREET 1:		140 GREENWICH AVENUE
		CITY:			GREENWICH
		STATE:			CT
		ZIP:			06830

	FORMER NAME:	
		FORMER CONFORMED NAME:	GABELLI GROUP CAPITAL PARTNERS INC
		DATE OF NAME CHANGE:	20030604

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			GAMCO INVESTORS, INC. ET AL
		CENTRAL INDEX KEY:			0000807249
		STATE OF INCORPORATION:			NY
		FISCAL YEAR END:			1031

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-11499
		FILM NUMBER:		051127182

	BUSINESS ADDRESS:	
		STREET 1:		ONE CORPORATE CENTER
		CITY:			RYE
		STATE:			NY
		ZIP:			10580-1434
		BUSINESS PHONE:		9149215128

	MAIL ADDRESS:	
		STREET 1:		ONE CORPORATE CENTER
		CITY:			RYE
		STATE:			NY
		ZIP:			10580

	FORMER NAME:	
		FORMER CONFORMED NAME:	GABELLI ASSET MANAGEMENT INC ET AL
		DATE OF NAME CHANGE:	20020828

	FORMER NAME:	
		FORMER CONFORMED NAME:	GABELLI FUNDS INC ET AL
		DATE OF NAME CHANGE:	19940714
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2005-10-05</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000795403</issuerCik>
        <issuerName>WATTS WATER TECHNOLOGIES INC</issuerName>
        <issuerTradingSymbol>WTS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0000807249</rptOwnerCik>
            <rptOwnerName>GAMCO INVESTORS, INC. ET AL</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>ONE CORPORATE CENTER</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>RYE</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10580</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001185533</rptOwnerCik>
            <rptOwnerName>GABELLI MARIO J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O GAMCO INVESTORS, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>ONE CORPORATE CENTER</rptOwnerStreet2>
            <rptOwnerCity>RYE</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10580</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001238894</rptOwnerCik>
            <rptOwnerName>GGCP, INC.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>140 GREENWICH AVENUE</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>GREENWICH</rptOwnerCity>
            <rptOwnerState>CT</rptOwnerState>
            <rptOwnerZipCode>06830</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2005-10-05</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>10000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>27.8134</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>13000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By: Investment Partnership</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">The Reporting Persons have less than a 100% interest in this entity.  The amount of securities reported as beneficially owned reflects the total amount of securities held by this entity which is greater than the Reporting Persons indirect pecuniary interests.  The Reporting Persons hereby disclaim ownership of these securities in excess of their pecuniary interests.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/ James E. McKee                    Attorney-in-Fact for MARIO J. GABELLI and GGCP, INC. and Secretary for GAMCO INVESTORS, INC.</signatureName>
        <signatureDate>2005-10-06</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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