POWER OF ATTORNEY

	Know all by these presents, that the undersigned hereby
constitutes and appoints each JAMES M. JASKA, RICHARD A. LEMMON,
LI-SAN HWANG and JANIS B. SALIN, signing singly, the undersigned's
true and lawful attorney-in-fact to:

(1)		execute for and on behalf of the undersigned, in the
undersigned's capacity as an officer of TETRA TECH, INC. (the
"Company"), Forms 3, 4, and 5 in accordance with Section 16(a) of the
Securities Exchange Act of 1934 and the rules thereunder;

(2)		do and perform any and all acts for and on behalf of
the undersigned which may be necessary or desirable to complete and
execute any such Form 3, 4, or 5, complete and execute any amendment
or amendments thereto, and timely file such form with the United States
Securities and Exchange Commission and any stock exchange or similar
authority; and

(3)	take any other action of any type whatsoever in connection with
the foregoing which, in the opinion of such attorney-in-fact, may be of
benefit to, in the best interest of, or legally required by, the
undersigned, it being understood that the documents executed by such
attorney-in-fact on behalf of the undersigned pursuant to this Power of
Attorney shall be in such form and shall contain such terms and
conditions as such attorney-in-fact may approve in such
attorney-in-fact's discretion.

	The undersigned hereby grants to each such attorney-in-fact
full power and authority to do and perform any and every act and thing
whatsoever requisite, necessary, or proper to be done in the exercise
of any of the rights and powers herein granted, as fully to all intents
and purposes as the undersigned might or could do if personally
present, with full power of substitution or revocation, hereby
ratifying and confirming all that such attorney-in-fact, or such
attorney-in-fact's substitute or substitutes, shall lawfully do or
cause to be done by virtue of this power of attorney and the rights
and powers herein granted.  The undersigned acknowledges that the
foregoing attorneys-in-fact, in serving in such capacity at the request
of the undersigned, are not assuming, nor is the Company assuming, any
of the undersigned's responsibilities to comply with Section 16 of the
Securities Exchange Act of 1934.

	This Power of Attorney shall remain in full force and effect
until the undersigned is no longer required to file Forms 3, 4, and 5
with respect to the undersigned's holdings of and transactions in
securities issued by the Company, unless earlier revoked by the
undersigned in a signed writing delivered to the foregoing
attorneys-in-fact.

	IN WITNESS WHEREOF, the undersigned has caused this Power of
Attorney to be executed as of this 21st day of January 2004.



		/s/  STEVEN M. BURDICK