    <SEC-DOCUMENT>0001047469-16-009736-index.html : 20160119
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    <ACCEPTANCE-DATETIME>20160119131352
    ACCESSION NUMBER:		0001047469-16-009736
    CONFORMED SUBMISSION TYPE:	DEF 14A
    PUBLIC DOCUMENT COUNT:		19
    CONFORMED PERIOD OF REPORT:	20160303
    FILED AS OF DATE:		20160119
    DATE AS OF CHANGE:		20160119
    EFFECTIVENESS DATE:		20160119

    FILER:

    	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:			0928

    	FILING VALUES:
    		FORM TYPE:		DEF 14A
    		SEC ACT:		1934 Act
    		SEC FILE NUMBER:	000-19655
    		FILM NUMBER:		161347725

    	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
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