<SEC-DOCUMENT>0001047469-20-000253-index.html : 20200115
<SEC-HEADER>0001047469-20-000253.hdr.sgml : 20200115
<ACCEPTANCE-DATETIME>20200115160350
ACCESSION NUMBER:		0001047469-20-000253
CONFORMED SUBMISSION TYPE:	DEF 14A
PUBLIC DOCUMENT COUNT:		42
CONFORMED PERIOD OF REPORT:	20200226
FILED AS OF DATE:		20200115
DATE AS OF CHANGE:		20200115
EFFECTIVENESS DATE:		20200115

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:			0929

	FILING VALUES:
		FORM TYPE:		DEF 14A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-19655
		FILM NUMBER:		20528349

	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>DEF 14A
<SEQUENCE>1
<FILENAME>a2240435zdef14a.htm
<DESCRIPTION>DEF 14A
<TEXT>
Document 1 - file: a2240435zdef14a.htm
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>2 <FILENAME>g528364.jpg <DESCRIPTION>G528364.JPG <TEXT> Document 2 - file: g528364.jpg
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</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>19 <FILENAME>g329526.jpg <DESCRIPTION>G329526.JPG <TEXT> Document 19 - file: g329526.jpg
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</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>25 <FILENAME>g487626.jpg <DESCRIPTION>G487626.JPG <TEXT> Document 25 - file: g487626.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>26 <FILENAME>g741613.jpg <DESCRIPTION>G741613.JPG <TEXT> Document 26 - file: g741613.jpg
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</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>29 <FILENAME>g93273.jpg <DESCRIPTION>G93273.JPG <TEXT> Document 29 - file: g93273.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>30 <FILENAME>g837.jpg <DESCRIPTION>G837.JPG <TEXT> Document 30 - file: g837.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>31 <FILENAME>g684935.jpg <DESCRIPTION>G684935.JPG <TEXT> Document 31 - file: g684935.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>32 <FILENAME>g408076.jpg <DESCRIPTION>G408076.JPG <TEXT> Document 32 - file: g408076.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>33 <FILENAME>g436095.jpg <DESCRIPTION>G436095.JPG <TEXT> Document 33 - file: g436095.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>34 <FILENAME>g434413.jpg <DESCRIPTION>G434413.JPG <TEXT> Document 34 - file: g434413.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>35 <FILENAME>g777959.jpg <DESCRIPTION>G777959.JPG <TEXT> Document 35 - file: g777959.jpg
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</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>38 <FILENAME>g986043.jpg <DESCRIPTION>G986043.JPG <TEXT> Document 38 - file: g986043.jpg
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</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>40 <FILENAME>g431317.jpg <DESCRIPTION>G431317.JPG <TEXT> Document 40 - file: g431317.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>41 <FILENAME>g637387.jpg <DESCRIPTION>G637387.JPG <TEXT> Document 41 - file: g637387.jpg
</DOCUMENT> <DOCUMENT> <TYPE>GRAPHIC <SEQUENCE>42 <FILENAME>g16342bci001.gif <DESCRIPTION>G16342BCI001.GIF <TEXT> Document 42 - file: g16342bci001.gif
</DOCUMENT> </SEC-DOCUMENT>