FORM 4 Check this box if no longer subject to Section 16. Form 4 or Form 5 obligations may continue. See Instruction 1(b).

UNITED STATES SECURITIES AND EXCHANGE COMMISSION Washington, D.C. 20549 STATEMENT OF CHANGES IN BENEFICIAL OWNERSHIP OF SECURITIES Filed pursuant to Section 16(a) of the Securities Exchange Act of 1934, Section 17(a) of the Public Utility Holding Company Act of 1935 or Section 30(h) of the Investment Company Act of 1940

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(Print or Type Responses)

1. Name and Address of Reporting Person * BATRACK DAN L   2. Issuer Name and Ticker or Trading Symbol TETRA TECH INC [TTEK] 5. Relationship of Reporting Person(s) to Issuer (Check all applicable) __X__ Director _____ 10% Owner __X__ Officer (give title below) _____ Other (specify below) CHAIRMAN, CEO & PRESIDENT (Last) (First) (Middle) 3475 EAST FOOTHILL BOULEVARD 3. Date of Earliest Transaction (Month/Day/Year) 11/20/2018 (Street) PASADENA,, CA 91107 4. If Amendment, Date Original Filed(Month/Day/Year) 6. Individual or Joint/Group Filing(Check Applicable Line) _X_ Form filed by One Reporting Person ___ Form filed by More than One Reporting Person (City) (State) (Zip) Table I - Non-Derivative Securities Acquired, Disposed of, or Beneficially Owned

1.Title of Security (Instr. 3) 2. Transaction Date (Month/Day/Year) 2A. Deemed Execution Date, if any (Month/Day/Year) 3. Transaction Code (Instr. 8) 4. Securities Acquired (A) or Disposed of (D) (Instr. 3, 4 and 5) 5. Amount of Securities Beneficially Owned Following Reported Transaction(s) (Instr. 3 and 4) 6. Ownership Form: Direct (D) or Indirect (I) (Instr. 4) 7. Nature of Indirect Beneficial Ownership (Instr. 4) Code V Amount (A) or (D) Price COMMON STOCK 11/20/2018   F   2,199 (1) (2) D $ 63.44 268,638 D   COMMON STOCK 11/20/2018   F   172 (3) D $ 63.44 268,466 D   COMMON STOCK 11/21/2018   F   3,883 (4) D $ 62.68 264,583 D

Reminder: Report on a separate line for each class of securities beneficially owned directly or indirectly.
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Table II - Derivative Securities Acquired, Disposed of, or Beneficially Owned
(e.g., puts, calls, warrants, options, convertible securities)

1. Title of Derivative Security (Instr. 3)

2. Conversion or Exercise Price of Derivative Security

3. Transaction Date (Month/Day/Year)

3A. Deemed Execution Date, if any (Month/Day/Year)

4. Transaction Code (Instr. 8)

5. Number of Derivative Securities Acquired (A) or Disposed of (D) (Instr. 3, 4, and 5)

6. Date Exercisable and Expiration Date (Month/Day/Year)

7. Title and Amount of Underlying Securities (Instr. 3 and 4)

8. Price of Derivative Security (Instr. 5)

9. Number of Derivative Securities Beneficially Owned Following Reported Transaction(s) (Instr. 4)

10. Ownership Form of Derivative Security: Direct (D) or Indirect (I) (Instr. 4)

11. Nature of Indirect Beneficial Ownership (Instr. 4)

Code

V

(A)

(D)

Date Exercisable

Expiration Date

Title

Amount or Number of Shares

Reporting Owners

Reporting Owner Name / Address	Relationships
	Director	10% Owner	Officer	Other
BATRACK DAN L 3475 EAST FOOTHILL BOULEVARD PASADENA,, CA 91107	X		CHAIRMAN, CEO & PRESIDENT

Signatures

/s/ Preston Hopson III, Attorney-in-fact for Dan L. Batrack		11/21/2018
**Signature of Reporting Person		Date

Explanation of Responses:

*	If the form is filed by more than one reporting person, see Instruction 4(b)(v).
**	Intentional misstatements or omissions of facts constitute Federal Criminal Violations. See 18 U.S.C. 1001 and 15 U.S.C. 78ff(a).
(1)	Represents the shares underlying performance share units (PSUs) which vested on 11/20/2018 and were withheld to satisfy the related FICA obligations.
(2)	The PSUs vested on 11/20/2018 are subject to the Reporting Person's deferral into the Issuer's Deferred Compensation Plan, and will be settled in shares of the Issuer's common stock according to the Reporting Person's election distribution schedule.
(3)	Represents the shares underlying restricted stock units (RSUs) which vested on 11/20/2018 and were withheld to satisfy the related FICA obligations.
(4)	Represents the shares underlying RSUs which vested on 11/21/2018 and were withheld to pay the related tax liability.

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