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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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 Yk2fd8yvwRHWthuWJB/qqA==

<SEC-DOCUMENT>0000052466-04-000089.txt : 20041123
<SEC-HEADER>0000052466-04-000089.hdr.sgml : 20041123
<ACCEPTANCE-DATETIME>20041123092832
ACCESSION NUMBER:		0000052466-04-000089
CONFORMED SUBMISSION TYPE:	4/A
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20041122
FILED AS OF DATE:		20041123
DATE AS OF CHANGE:		20041123

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			IONICS INC
		CENTRAL INDEX KEY:			0000052466
		STANDARD INDUSTRIAL CLASSIFICATION:	SPECIAL INDUSTRY MACHINERY, NEC [3559]
		IRS NUMBER:				042068530
		STATE OF INCORPORATION:			MA
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		65 GROVE ST
		CITY:			WATERTOWN
		STATE:			MA
		ZIP:			02172
		BUSINESS PHONE:		6179262500

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BROWN STEPHEN L
		CENTRAL INDEX KEY:			0001162739

	FILING VALUES:
		FORM TYPE:		4/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-07211
		FILM NUMBER:		041162407

	BUSINESS ADDRESS:	
		STREET 1:		C/O ADVENT INTERNATIONAL CORP
		STREET 2:		75 STATE STREET
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02109
		BUSINESS PHONE:		6179262500

	MAIL ADDRESS:	
		STREET 1:		C/O IONICS, INCORPORATED
		STREET 2:		65 GROVE STREET
		CITY:			WATERTOWN
		STATE:			MA
		ZIP:			02472

	FORMER NAME:	
		FORMER CONFORMED NAME:	BROWN STEPHEN L /
		DATE OF NAME CHANGE:	20011127
</SEC-HEADER>
<DOCUMENT>
<TYPE>4/A
<SEQUENCE>1
<FILENAME>amended-slbrown2004_ex.xml
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2004-11-22</periodOfReport>

    <dateOfOriginalSubmission>2004-11-17</dateOfOriginalSubmission>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000052466</issuerCik>
        <issuerName>IONICS INC</issuerName>
        <issuerTradingSymbol>ION</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001162739</rptOwnerCik>
            <rptOwnerName>BROWN STEPHEN L</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>180 BEACON STREET</rptOwnerStreet1>
            <rptOwnerStreet2>APT. 14G</rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02116</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2004-11-22</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>727</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>30.95</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3255</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Represents shares acquired by reporting person as payment of retainer fee pursuant to Ionics, Incorporated 1998 Non-Employee
Directors Fee Plan in a transaction exempt under Rule 16b-3.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/Stephen L. Brown</signatureName>
        <signatureDate>2004-11-22</signatureDate>
    </ownerSignature>
</ownershipDocument>

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