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SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
Under the Securities Exchange Act of 1934
(Amendment No.___1_____)*
Tetra Tech Inc
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(Name of Issuer)
Common Stock (Par Value $0.01)
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(Title of Class of Securities)
88162G103
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(CUSIP Number)
Check the following box if a fee is being paid with this statement [ ].
(A fee is not required only if the filing person: (1) has a previous statement
on file reporting beneficial ownership of more than five percent of the class of
securities described in Item 1; and (2) has filed no amendment subsequent
thereto reporting beneficial ownership of five percent or less of such
class.)(See Rule 13d-7.)
* The remainder of this cover page shall be filled out for a reporting person's
initial filing on this form with respect to the subject class of securities, and
for any subsequent amendment containing information which would alter the
disclosures provided in a prior cover page.
The information required in the remainder of this cover page shall not be deemed
to be "filed" for the purpose of Section 18 of the Securities Exchange Act of
1934 ("Act") or otherwise subject to the liabilities of that section of the Act
but shall be subject to all other provisions of the Act (however, see the
Notes).
(Continued on following pages)
Page 1 of 6 Pages
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CUSIP No. 88162G103 Page 2 of 6
1. NAME OF REPORTING PERSON
S.S. OR I.R.S. IDENTIFICATION NO. OF ABOVE PERSON
Brown Investment Advisory & Trust Company ("BIATC"), its wholly owned
subsidiary, Brown Advisory Incorporated ("BAI"). 52-1811121
2. CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
(a) [ ]
(b) [x]
3. SEC USE ONLY
4. CITIZENSHIP OR PLACE OF ORGANIZATION
Brown Investment Advisory & Trust Company and Brown Advisory Incorporated
are Maryland corporations.
NUMBER OF 5 SOLE VOTING POWER
SHARES BIATC 616750 shares
BAI 0 shares
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616750 shares
BENEFICIALLY 6 SHARED VOTING POWER
OWNED BY BIATC 0 shares
BAI 0 shares
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0 shares
EACH REPORTING 7 SOLE DISPOSITIVE POWER
PERSON WITH BIATC 1576428 shares
BAI 0 shares
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1576428 shares
8 SHARED DISPOSITIVE POWER
BIATC 0 shares
BAI 0 shares
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0 shares
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CUSIP No. 88162G103 Page 3 of 6
9. AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
BIATC 1576428 shares
BAI 0 shares
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1576428 shares
10. CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES* [ ]
11. PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (9)
BIATC 4.09%
BAI 0.00%
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4.09%
12. TYPE OF REPORTING PERSON*
BIATC - BK
BAI - IA
*SEE INSTRUCTIONS BEFORE FILLING OUT
Item 1. (a) NAME OF ISSUER: Tetra Tech Inc
(b) Address of Issuer's Principal Executive Offices:
670 N Rosemead Boulevard, Pasadena CA 91107
Item 2. (a) NAME OF PERSON FILING:
Brown Investment Advisory & Trust Company ("BIATC"), its wholly
owned subsidiary, Brown Advisory Incorporated ("BAI").
(b) ADDRESS OF PRINCIPAL BUSINESS OFFICE:
19 South Street
Baltimore, Maryland 21202
(c) CITIZENSHIP:
Brown Investment Advisory & Trust Company and Brown Advisory
Incorporated are Maryland corporations.
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CUSIP No. 88162G103 Page 4 of 6
(d) TITLE OF CLASS OF SECURITIES:
Common Stock of ($0.01 par) of Tetra Tech Incorporated
(e) CUSIP Number:
88162G103
Item 3. If this statement is filed pursuant to Rules 13d-1(b), or 13d-2(b),
check whether the person filing is a:
For BIATC
(b) [x] Bank as defined in section 3(a)(6) of the Act
For BAI
(e) [x] Investment Adviser registered under section 203 of the
Investment Advisers Act of 1940
Item 4. OWNERSHIP:
(a) AMOUNT BENEFICIALLY OWNED: As of March 31, 2000
BIATC 1576428 shares
BAI 0 shares
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1576428 shares
(b) PERCENT OF CLASS:
BIATC 4.09%
BAI 0.00%
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4.09%
(c) Number of shares as to which such person has:
(i) sole power to vote or to direct the vote:
BIATC 616750 shares
BAI 0 shares
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616750 shares
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CUSIP No. 88162G103 Page 5 of 6
(ii) shared power to vote or to direct the vote:
BIATC 0 shares
BAI 0 shares
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0 shares
(iii) sole power to dispose or to direct the disposition of:
BIATC 1576428 shares
BAI 0 shares
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1576428 shares
(iv) shared power to dispose or to direct the disposition of:
BIATC 0 shares
BAI 0 shares
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0 shares
Item 5. OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS.
Not applicable
Item 6. OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER PERSON.
Not applicable
Item 7. IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH ACQUIRED THE
SECURITY BEING REPORTED ON BY THE PARENT HOLDING COMPANY.
Not applicable
Item 8. IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF THE GROUP.
Not applicable
Item 9. NOTICE OF DISSOLUTION OF GROUP.
Not applicable
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CUSIP No. 88162G103 Page 6 of 6
Item 10. CERTIFICATION.
By signing below I certify that, to the best of my knowledge and
belief, the securities referred to above were acquired in the ordinary
course of business and were not acquired for the purpose of and do not
have the effect of changing or influencing the control of the issuer of
such securities and were not acquired in connection with or as a
participant in any transaction having such purpose or effect.
SIGNATURE:
After reasonable inquiry and to the best of my knowledge and belief, I
certify that the information set forth in this statement is true,
complete and correct.
Date: As of March 31, 2000
Signature: Brown Investment Advisory & Trust Company
By: /s/ James E. Hieber
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Title: Vice President
Signature: Brown Advisory Incorporated
By: /s/ James E. Hieber
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Title: Vice President
