<SEC-DOCUMENT>0000831641-19-000040.txt : 20190403
<SEC-HEADER>0000831641-19-000040.hdr.sgml : 20190403
<ACCEPTANCE-DATETIME>20190403172830
ACCESSION NUMBER:		0000831641-19-000040
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20190401
FILED AS OF DATE:		20190403
DATE AS OF CHANGE:		20190403

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			SMITH ALBERT E
		CENTRAL INDEX KEY:			0001194005

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-19655
		FILM NUMBER:		19730185

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:			0929

	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>
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<SEQUENCE>1
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                    <value>D</value>
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            <exerciseDate>
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                <value>2024-11-21</value>
            </expirationDate>
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    <footnotes>
        <footnote id="F1">Pursuant to a 10b5-1 Plan.</footnote>
        <footnote id="F2">The option became exercisable as to 100% of the shares on the anniversary of the grant date.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Preston Hopson III, Attorney-in-fact for Albert E. Smith</signatureName>
        <signatureDate>2019-04-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</SEC-DOCUMENT>
