<SEC-DOCUMENT>0000831641-21-000092.txt : 20211122
<SEC-HEADER>0000831641-21-000092.hdr.sgml : 20211122
<ACCEPTANCE-DATETIME>20211122194008
ACCESSION NUMBER:		0000831641-21-000092
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20211118
FILED AS OF DATE:		20211122
DATE AS OF CHANGE:		20211122

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			BATRACK DAN L
		CENTRAL INDEX KEY:			0001207854

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-19655
		FILM NUMBER:		211434251

	MAIL ADDRESS:	
		STREET 1:		3475 EAST FOOTHILL BOULEVARD
		CITY:			PASADENA
		STATE:			CA
		ZIP:			91107

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			TETRA TECH INC
		CENTRAL INDEX KEY:			0000831641
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-ENGINEERING SERVICES [8711]
		IRS NUMBER:				954148514
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1003

	BUSINESS ADDRESS:	
		STREET 1:		3475 EAST FOOTHILL BOULEVARD
		CITY:			PASADENA
		STATE:			CA
		ZIP:			91107
		BUSINESS PHONE:		6263514664

	MAIL ADDRESS:	
		STREET 1:		3475 EAST FOOTHILL BOULEVARD
		CITY:			PASADENA
		STATE:			CA
		ZIP:			91107
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
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<DESCRIPTION>FORM 4
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        <issuerName>TETRA TECH INC</issuerName>
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    <footnotes>
        <footnote id="F1">The award becomes vested as to 25% of the RSUs on the anniversary of the grant date.</footnote>
        <footnote id="F2">Represents the combined number of shares withheld to pay the related tax liability on a total of 17,237 restricted stock units (RSUs) which vested on 11/18/2021.</footnote>
        <footnote id="F3">Amount of securities beneficially owned have also been updated to reflect the acquisition of 58 shares of common stock pursuant to the Tetra Tech, Inc. Employee Stock Purchase Plan (ESPP) on December 15, 2020.</footnote>
        <footnote id="F4">The RSUs become vested as to 25% of the shares on November 18, 2019, and the anniversary of that date going forward until fully vested.</footnote>
        <footnote id="F5">The RSUs become vested as to 25% of the shares on November 18, 2020, and the anniversary of that date going forward until fully vested.</footnote>
        <footnote id="F6">The RSUs become vested as to 25% of the shares on November 18, 2021, and the anniversary of that date going forward until fully vested.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Preston Hopson, Attorney-in-fact for Dan L. Batrack</signatureName>
        <signatureDate>2021-11-21</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
