<PAGE>
PROSPECTUS
TETRA TECH, INC.
402,680 SHARES OF COMMON STOCK
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The stockholders of Tetra Tech, Inc. listed herein are offering and
selling 402,680 shares of Common Stock of Tetra Tech, Inc. under this
prospectus.
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INVESTING IN TETRA TECH, INC. COMMON STOCK INVOLVES RISKS.
SEE "RISK FACTORS" BEGINNING ON PAGE 2.
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Certain of the selling stockholders obtained their shares of Common
Stock on May 21, 1999 in connection with Tetra Tech, Inc.'s acquisition of
BAHA Communications, Inc., and the other selling stockholders obtained their
shares on September 23, 1999 in connection with Tetra Tech, Inc.'s
acquisition of PDR Engineers, Inc. Some or all of the selling stockholders
expect to sell their shares.
The selling stockholders may offer their shares of Common Stock
through public or private transactions, on or off the Nasdaq National Market,
at prevailing market prices, or at privately negotiated prices.
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Tetra Tech, Inc. Common Stock is traded on the Nasdaq National Market
under the symbol "WATR." On February 24, 2000, the closing price of the Common
Stock on the Nasdaq National Market was $21-7/16 per share.
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THE SECURITIES AND EXCHANGE COMMISSION AND STATE SECURITIES REGULATORS
HAVE NOT APPROVED OR DISAPPROVED THESE SECURITIES, OR DETERMINED IF THIS
PROSPECTUS IS TRUTHFUL OR COMPLETE. ANY REPRESENTATION TO THE CONTRARY IS A
CRIMINAL OFFENSE.
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THE DATE OF THIS PROSPECTUS IS FEBRUARY 24, 2000
<PAGE>
THE COMPANY
Tetra Tech, Inc. is a leading provider of specialized management
consulting and technical services in three principal business areas: resource
management, infrastructure and communications. As a specialized management
consultant, we assist our clients in defining problems and developing
innovative and cost-effective solutions. Our management consulting services
are complemented by our technical services. These technical services, which
implement solutions, include research and development, applied science,
engineering and architectural design, construction management, and operations
and maintenance. Our clients include a diverse base of public and private
organizations located in the United States and internationally.
Since our initial public offering in December 1991, we have increased
the size and scope of our business and have expanded our service offerings
through a series of strategic acquisitions and internal growth. We have more
than 3,600 employees worldwide, 3,500 of whom are located in North America in
more than 100 locations. In addition, we have established a presence in Asia,
South America and Europe.
Our principal executive offices are located at 670 North Rosemead
Boulevard, Pasadena, California 91107, and our telephone number is (626)
351-4664. Our website is located at www.tetratech.com. Information contained
in our website is not a part of this prospectus.
USE OF PROCEEDS
The selling stockholders are offering all of the shares of Common
Stock covered by this prospectus. We will not receive any proceeds from the
sales of these shares.
RISK FACTORS
AN INVESTMENT IN THE SHARES OF COMMON STOCK OFFERED BY THIS
PROSPECTUS INVOLVES A HIGH DEGREE OF RISK. YOU SHOULD CAREFULLY REVIEW THE
FOLLOWING RISK FACTORS AS WELL AS THE OTHER INFORMATION SET FORTH IN THIS
PROSPECTUS BEFORE MAKING AN INVESTMENT.
SOME OF THE INFORMATION IN THIS PROSPECTUS OR INCORPORATED BY
REFERENCE IN THIS PROSPECTUS CONTAINS FORWARD-LOOKING STATEMENTS THAT INVOLVE
SUBSTANTIAL RISKS AND UNCERTAINTIES. YOU CAN IDENTIFY THESE STATEMENTS BY
FORWARD-LOOKING WORDS SUCH AS "MAY," "WILL," "EXPECT," "ANTICIPATE,"
"BELIEVE," "ESTIMATE" AND "CONTINUE" OR SIMILAR WORDS. YOU SHOULD READ
STATEMENTS THAT CONTAIN THESE WORDS CAREFULLY BECAUSE THEY: (1) DISCUSS OUR
FUTURE EXPECTATIONS; (2) CONTAIN PROJECTIONS OF OUR FUTURE OPERATING RESULTS
OR OF OUR FUTURE FINANCIAL CONDITION; OR (3) STATE OTHER "FORWARD-LOOKING"
INFORMATION. WE BELIEVE IT IS IMPORTANT TO COMMUNICATE OUR EXPECTATIONS TO
OUR INVESTORS. THERE MAY BE EVENTS IN THE FUTURE, HOWEVER, THAT WE ARE NOT
ACCURATELY ABLE TO PREDICT OR OVER WHICH WE HAVE NO CONTROL. THE RISK FACTORS
LISTED IN THIS SECTION, AS WELL AS ANY CAUTIONARY LANGUAGE IN THIS
PROSPECTUS, PROVIDE EXAMPLES OF RISKS, UNCERTAINTIES AND EVENTS THAT MAY
CAUSE OUR ACTUAL RESULTS TO DIFFER MATERIALLY FROM THE EXPECTATIONS WE
DESCRIBE IN OUR FORWARD-LOOKING STATEMENTS. BEFORE YOU INVEST IN OUR COMMON
STOCK, YOU SHOULD BE AWARE THAT THE OCCURRENCE OF ANY OF THE EVENTS DESCRIBED
IN THESE RISK FACTORS AND ELSEWHERE IN THIS PROSPECTUS COULD HAVE A MATERIAL
ADVERSE EFFECT ON OUR BUSINESS, FINANCIAL CONDITION AND OPERATING RESULTS AND
THAT UPON THE OCCURRENCE OF ANY OF THESE EVENTS, THE TRADING PRICE OF OUR
COMMON STOCK COULD DECLINE AND YOU COULD LOSE ALL OR PART OF YOUR INVESTMENT.
THERE ARE RISKS ASSOCIATED WITH OUR ACQUISITION STRATEGY THAT COULD ADVERSELY
IMPACT OUR BUSINESS AND OPERATING RESULTS
A significant part of our growth strategy is to acquire other
companies that complement our lines of business or that broaden our
geographic presence. During fiscal 1999, we purchased eleven companies in
nine separate transactions. During the three months ended January 2, 2000, we
purchased two companies in one transaction. We expect to continue to acquire
companies as an element of our growth strategy. Acquisitions involve certain
risks that could cause our actual growth or operating results to differ from
our expectations or the expectations of security analysts. For example:
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- We may not be able to identify suitable acquisition candidates or to
acquire additional companies on favorable terms;
- We compete with others to acquire companies. We believe that this
competition will increase and may result in decreased availability or
increased price for suitable acquisition candidates;
- We may not be able to obtain the necessary financing, on favorable
terms or at all, to finance any potential acquisitions;
- We may ultimately fail to consummate an acquisition even if we
announce that we plan to acquire a company;
- We may fail to successfully integrate or manage these acquired
companies due to differences in business backgrounds or corporate
cultures;
- These acquired companies may not perform as we expect;
- We may find it difficult to provide a consistent quality of service
across our geographically diverse operations; and
- If we fail to successfully integrate any acquired company, our
reputation could be damaged. This could make it more difficult to
market our services or to acquire additional companies in the future.
In addition, our acquisition strategy may divert management's attention away
from our primary service offerings, result in the loss of key clients or
personnel and expose us to unanticipated liabilities.
Finally, acquired companies that derive a significant portion of their
revenues from the Federal government and that do not follow the same cost
accounting policies and billing procedures as we do may be subject to larger
cost disallowances for greater periods than we typically encounter. If we fail
to determine the existence of unallowable costs and establish appropriate
reserves in advance of an acquisition we may be exposed to material
unanticipated liabilities, which could have a material adverse effect on our
business.
OUR QUARTERLY OPERATING RESULTS MAY FLUCTUATE SIGNIFICANTLY, WHICH COULD HAVE A
NEGATIVE EFFECT ON THE PRICE OF OUR COMMON STOCK
Our quarterly revenues, expenses and operating results may fluctuate
significantly because of a number of factors, including:
- The seasonality of the spending cycle of our public sector clients,
notably the Federal government;
- Employee hiring and utilization rates;
- The number and significance of client engagements commenced and
completed during a quarter;
- Delays incurred in connection with an engagement;
- The ability of our clients to terminate engagements without penalties;
- The size and scope of engagements;
- The timing of expenses incurred for corporate initiatives;
- The timing and size of the return on investment capital; and
- General economic and political conditions.
<PAGE>
Variations in any of these factors could cause significant fluctuations in our
operating results from quarter to quarter and could result in net losses.
THE VALUE OF OUR COMMON STOCK COULD CONTINUE TO BE VOLATILE
The trading price of our Common Stock has fluctuated widely. In
addition, in recent years the stock market has experienced extreme price and
volume fluctuations. The overall market and the price of our Common Stock may
continue to fluctuate greatly. The trading price of our Common Stock may be
significantly affected by various factors, including:
- Quarter to quarter variations in our operating results;
- Changes in environmental legislation;
- Changes in investors' and analysts' perception of the business risks
and conditions of our business;
- Broader market fluctuations; and
- General economic or political conditions.
IF WE ARE NOT ABLE TO SUCCESSFULLY MANAGE OUR GROWTH STRATEGY, OUR BUSINESS
AND RESULTS OF OPERATIONS MAY BE ADVERSELY AFFECTED
We are growing rapidly. Our growth presents numerous managerial,
administrative, operational and other challenges. Our ability to manage the
growth of our operations will require us to continue to improve our
operational, financial and human resource management information systems and
our other internal systems and controls. In addition, our growth will
increase our need to attract, develop, motivate and retain both our
management and professional employees. The inability of our management to
manage our growth effectively or the inability of our employees to achieve
anticipated performance or utilization levels, could have a material adverse
effect on our business.
THE LOSS OF KEY PERSONNEL OR OUR INABILITY TO ATTRACT AND RETAIN QUALIFIED
PERSONNEL COULD SIGNIFICANTLY DISRUPT OUR BUSINESS
We depend upon the efforts and skills of our executive officers,
senior managers and consultants. With limited exceptions, we do not have
employment agreements with any of these individuals. The loss of the services
of any of these key personnel could adversely affect our business. Although
we have obtained non-compete agreements from certain principals and
stockholders of each of the companies we have acquired, we generally do not
have non-compete or employment agreements with key employees who were not
once equity shareholders of these companies. We do not maintain key-man life
insurance policies on any of our executive officers or senior managers.
Our future growth and success depends on our ability to attract and
retain qualified scientists and engineers. The market for these professionals
is competitive and we may not be able to attract and retain such
professionals.
CHANGES IN EXISTING LAWS AND REGULATIONS COULD REDUCE THE DEMAND FOR OUR
SERVICES
A significant amount of our resource management business is generated
either directly or indirectly as a result of existing Federal and state
governmental laws, regulations and programs. Any changes in these laws or
regulations that reduce funding or affect the sponsorship of these programs
could reduce the demand for our services and could have a material adverse
effect on our business.
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OUR REVENUES FROM AGENCIES OF THE FEDERAL GOVERNMENT ARE CONCENTRATED, AND A
REDUCTION IN SPENDING BY THESE AGENCIES COULD ADVERSELY AFFECT OUR BUSINESS
AND OPERATING RESULTS
Agencies of the Federal government are among our most significant
clients. During the three months ended January 2, 2000, approximately 30.4%
of our net revenue was derived from Federal agencies, of which 17.0% was
derived from the Department of Defense (DOD), 9.2% from the Environmental
Protection Agency (EPA), and 2.2% from the Department of Energy (DOE), and
2.0% from various other Federal government agencies. Some contracts with
Federal government agencies require annual funding approval and may be
terminated at their discretion. A reduction in spending by Federal government
agencies could limit the continued funding of our existing contracts with
them and could limit our ability to obtain additional contracts. These
limitations, if significant, could have a material adverse effect on our
business.
Additionally the failure of clients to pay significant amounts due us
for our services could adversely affect our business. For example, we
received notification from a Federal government agency that we are entitled
to payments in excess of our billings. However, the agency involved must
obtain specific funding approval for amounts owed to us and there can be no
assurance this funding approval will be obtained.
OUR CONTRACTS WITH GOVERNMENTAL AGENCIES ARE SUBJECT TO AUDIT, WHICH COULD
RESULT IN THE DISALLOWANCE OF CERTAIN COSTS
Contracts with the Federal government and other governmental agencies
are subject to audit. Most of these audits are conducted by the Defense
Contract Audit Agency (DCAA), which reviews our overhead rates, operating
systems and cost proposals. The DCAA may disallow costs if it determines that
we accounted for these costs incorrectly or in a manner inconsistent with
Cost Accounting Standards. A disallowance of costs by the DCAA, or other
governmental auditors, could have a material adverse effect on our business.
In September 1995, we acquired PRC Environmental Management, Inc.
(EMI). EMI also contracts with Federal government agencies and such contracts
are also subject to the same governmental audits. At the time of acquisition,
audits had not yet been completed or finalized. Accordingly, reserves were
established for potential disallowances. Since then, the DCAA has completed
audits of EMI's contracts for the fiscal years 1987 through 1995. As a result
of these audits and negotiations with the DCAA, the DCAA has disallowed to
date approximately $4.4 million in costs which have been applied against the
established reserves.
OUR BUSINESS AND OPERATING RESULTS COULD BE ADVERSELY AFFECTED BY LOSSES
UNDER FIXED-PRICE CONTRACTS OR TERMINATION OF CONTRACTS AT THE CLIENT'S
DISCRETION
We contract with Federal and state governments, as well as with the
private sector. These contracts are often subject to termination at the
discretion of the client with or without cause. Additionally, we enter into
various types of contracts with our clients, including fixed-price contracts.
Fixed-price contracts protect clients and expose us to a number of risks.
These risks include underestimation of costs, problems with new technologies,
unforeseen costs or difficulties, delays beyond our control and economic and
other changes that may occur during the contract period. Losses under
fixed-price contracts or termination of contracts at the discretion of the
client could have a material adverse effect on our business.
In fiscal 1999, we had a contract change with Tele-Communications,
Inc. involving three turnkey contracts. This change was due in part to
Tele-Communications, Inc.'s change in strategy from turnkey contracts to
direct service contracts in the upgrading of their network systems.
OUR INABILITY TO FIND QUALIFIED SUBCONTRACTORS COULD ADVERSELY AFFECT THE
QUALITY OF OUR SERVICE AND OUR ABILITY TO PERFORM UNDER CERTAIN CONTRACTS
Under some of our contracts, we depend on the efforts and skills of
subcontractors for the performance of certain tasks. Reliance on
subcontractors varies from project to project. In the three months ended
January 2, 2000, subcontractor costs comprised 24.1% of our gross revenue.
The absence of qualified subcontractors with whom we have a satisfactory
relationship could adversely affect the quality of our service and our
ability to perform under some of our contracts.
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OUR INDUSTRY IS HIGHLY COMPETITIVE AND WE MAY BE UNABLE TO COMPETE EFFECTIVELY
We provide specialized management consulting and technical services
to a broad range of public and private sector clients. The market for our
services is highly competitive and we compete with many other firms. These
firms range from small regional firms to large national firms which have
greater financial and marketing resources than ours.
We focus primarily on the resource management, infrastructure and
communications business areas. We provide services to our clients which
include Federal, state and local agencies, and organizations in the private
sector.
We compete for projects and engagements with a number of competitors
which can vary from 10 to 100 firms. Historically, clients have chosen among
competing firms based on the quality and timeliness of the firm's service. We
believe, however, that price has become an increasingly important factor.
We believe that our principal competitors include, in alphabetical
order, Black & Veatch LLP; Brown & Caldwell; Castle Tower Corporation; Camp,
Dresser & McKee; CH2M Hill Companies Ltd.; Dames & Moore Group; EA
Engineering, Science & Technology, Inc.; Earth Tech, Inc.; ICF Kaiser
International, Inc.; IT Group Inc.; Mastec, Inc.; Montgomery Watson; OSP
Consultants, Inc.; Quanta Services; Roy F. Weston, Inc.; URS Greiner
Corporation and Wireless Facilities, Inc.
OUR SERVICES EXPOSE US TO SIGNIFICANT RISKS OF LIABILITY AND OUR INSURANCE
POLICIES MAY NOT PROVIDE ADEQUATE COVERAGE
Our services involve significant risks of professional and other
liabilities which may substantially exceed the fees we derive from our
services. Our business activities could expose us to potential liability
under various environmental laws such as the Comprehensive Environmental
Response, Compensation and Liability Act of 1980 (CERCLA). In addition, we
sometimes contractually assume liability under indemnification agreements. We
cannot predict the magnitude of such potential liabilities.
We currently maintain comprehensive general liability, umbrella and
professional liability insurance policies. We believe that our insurance
policies are adequate for our business operations. Professional liability
policies are "claims made" policies. Thus, only claims made during the term
of the policy are covered. Should we terminate our professional liability
policies and not obtain retroactive coverage, we would be uninsured for
claims made after termination even if these claims are based on events or
acts that occurred during the term of the policy. Additionally, our insurance
policies may not protect us against potential liability due to various
exclusions and retentions. Should we expand into new markets, we may not be
able to obtain insurance coverage for such activities or, if insurance is
obtained, the dollar amount of any liabilities incurred could exceed our
insurance coverage. Partially or completely uninsured claims, if successful
and of significant magnitude, could have a material adverse affect on our
business.
WE MAY BE PRECLUDED FROM PROVIDING CERTAIN SERVICES DUE TO CONFLICT OF
INTEREST ISSUES
Many of our clients are concerned about potential or actual conflicts
of interest in retaining management consultants. Federal government agencies
have formal policies against continuing or awarding contracts that would
create actual or potential conflicts of interest with other activities of a
contractor. These policies, among other things, may prevent us from bidding
for or performing contracts resulting from or relating to certain work we
have performed for the government. In addition, services performed for a
private client may create a conflict of interest that precludes or limits our
ability to obtain work from other public or private organizations. We have,
on occasion, declined to bid on projects because of these conflicts of
interest issues.
<PAGE>
OUR INTERNATIONAL OPERATIONS EXPOSE US TO RISKS SUCH AS FOREIGN CURRENCY
FLUCTUATIONS
In the three months ended January 2, 2000, approximately 2.7% of our
net revenue was derived from the international marketplace. Some contracts
with our international clients are denominated in foreign currencies. As
such, these contracts contain inherent risks including foreign currency
exchange risk and the risk associated with expatriating funds from foreign
countries. If our international revenue increases, our exposure to foreign
currency fluctuations will also increase. We have entered into forward
exchange contracts to address certain foreign currency fluctuations.
SELLING STOCKHOLDERS
On May 21, 1999, we acquired BAHA Communications, Inc., a Nevada
corporation ("BAHA"), through the merger of BAHA Acquisition Corporation, a
Nevada corporation and our wholly-owned subsidiary, into BAHA. In connection
with this acquisition, we issued to the BAHA shareholders an aggregate of
166,155 shares of our Common Stock (as adjusted to reflect a post-closing
purchase price adjustment). Of the 166,155 shares, 29,272 shares are being
held in escrow to provide security for BAHA's generation of specified
operating profit during the 12-month period that commenced on June 1, 1999.
Depending upon BAHA's performance during this period, some or all of the
escrowed shares will be delivered to the former BAHA shareholders.
On September 3, 1999, we acquired PDR Engineers, Inc., a Kentucky
corporation ("PDR"), through the merger of PDR into PDR Acquisition
Corporation, a Delaware corporation and our wholly-owned subsidiary. In
<PAGE>
connection with this acquisition, PDR Acquisition Corporation changed its
name to PDR Engineers, Inc. and we issued to the PDR shareholders an
aggregate of 236,525 shares of our Common Stock.
Under a Registration Rights Agreement dated as of May 21, 1999 as to
the BAHA acquisition and a Registration Rights Agreement dated September 3,
1999 as to the PDR Acquisition, we agreed to register the shares of Common
Stock issued to the former BAHA and PDR shareholders and to use commercially
reasonable efforts to keep the registration statement effective until the
date on which all selling stockholders may sell their shares of Common Stock
under Rule 144 promulgated under the Securities Act of 1933, as amended (the
"Securities Act"), without any volume limitation. Our registration of the
shares of Common Stock does not necessarily mean that the selling
stockholders will sell all or any of the shares.
The shares listed below represent all of the shares that each selling
stockholder currently owns of our Common Stock (including shares held in
escrow). Except as otherwise noted, we know of no agreements among our
stockholders which relate to voting or investment power over our Common
Stock. Except as otherwise noted, the address of each of the first three
selling stockholders is c/o BAHA Communications, Inc., 6000 S. Eastern, Suite
9-E, Las Vegas, Nevada 89119, and the address of each of the other selling
stockholders is c/o PDR Engineers, Inc., 800 Corporate Drive, Suite 100,
Lexington, Kentucky 40503.
<TABLE>
<CAPTION>
SHARES
BENEFICIALLY NUMBER
OWNED OF
PRIOR SHARES
NAMES TO OFFERING %(1) OFFERED
- ---------------------------------- ----------- ------ ---------
<S> <C> <C> <C>
Tim Baker......................... 91,386 * 91,386
Mark Baker........................ 41,539 * 41,539
Dennis Baker...................... 33,230 * 33,230
Elbert C. Ray..................... 134,082 * 134,082
Steven D. Singleton............... 24,412 * 24,412
David B. Servis................... 30,849 * 30,849
Michael A. Cooper................. 47,182 * 47,182
</TABLE>
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* Represents less than 1% of the outstanding shares of Common Stock.
The first three selling stockholders listed above are employees of
BAHA and the other selling stockholders are employees of PDR. No selling
stockholder has had any material relationship with us, or any of our
predecessors or affiliates, other than as an employee. Because the selling
stockholders may sell all or part of their shares of Common Stock offered
hereby, no estimate can be given as to the number of shares of Common Stock
that will be held by any selling stockholder upon termination of any offering
made hereby.
PLAN OF DISTRIBUTION
We are registering the shares of Common Stock on behalf of the
selling stockholders. As used herein, "selling stockholders" includes donees
and pledgees selling shares received from a named selling shareholder after
the date of this Prospectus. This Prospectus may also be used by transferees
of the selling stockholders or by other persons acquiring shares, including
brokers who borrow the shares to settle short sales of shares of Common
Stock. We will bear all costs, expenses and fees in connection with the
registration of the shares offered hereby. The selling stockholders will bear
brokerage commissions and any similar selling expenses associated with the
sale of shares.
<PAGE>
The selling stockholders may offer their shares of Common Stock at
various times in one or more of the following transactions:
- on the Nasdaq National Market;
- in the over-the-counter market;
- in transactions other than on the Nasdaq National Market or in the
over-the-counter market;
- in connection with short sales of the shares of Common Stock;
- by pledge to secure debts and other obligations;
- in connection with the writing of non-traded and exchange-traded call
options, in hedge transactions and in settlement of other transactions
in standardized or over-the-counter options; or
- in any combination of any of the above transactions.
In connection with hedging transactions, broker-dealers or other
financial institutions may engage in short sales of the Common Stock in the
course of hedging the positions they assume with selling stockholders. The
selling stockholders may also enter into options or other transactions with
broker-dealers or other financial institutions, which require the delivery to
such broker-dealer or other financial institution of the shares offered
hereby, which shares may be resold pursuant to this prospectus (as
supplemented or amended to reflect such transaction).
The selling stockholders may sell their shares at market prices
prevailing at the time of sale, at prices related to such prevailing market
prices, at negotiated prices or at fixed prices. The selling shareholders may
use broker-dealers to sell their shares. If this happens, broker-dealers will
either receive discounts or commissions from purchasers of shares for whom
they acted as agents.
The selling stockholders have advised us that they have not entered
into any agreements, understandings or arrangements with any underwriters or
broker-dealers regarding the sale of their securities, nor is there an
underwriter or coordinating broker acting in connection with the proposed
sale of shares by the selling stockholders.
The selling stockholders and any broker-dealers that act in
connection with the sale of shares might be deemed to be "underwriters"
within the meaning of Section 2(11) of the Securities Act, and any
commissions received by such broker-dealers and any profit on the resale of
the shares sold by them while acting as principals might be deemed to be
underwriting discounts or commissions under the Securities Act. We have
agreed to indemnify each selling stockholder against certain liabilities,
including liabilities arising under the Securities Act. The selling
stockholders may agree to indemnify any agent, dealer or broker-dealer that
participates in transactions involving sales of the shares against certain
liabilities, including liabilities arising under the Securities Act.
Because the selling stockholders may be deemed to be "underwriters"
within the meaning of Section 2(11) of the Securities Act, the selling
stockholders will be subject to the prospectus delivery requirements of the
Securities Act. We have informed the selling stockholders that the
anti-manipulative provisions of Regulation M promulgated under the Securities
Exchange Act of 1934, as amended (the "Exchange Act"), may apply to their
sales in the market.
<PAGE>
The selling stockholders also may resell all or a portion of the
shares in open market transactions in reliance upon Rule 144 under the
Securities Act, provided they meet the criteria and conform to the
requirements of such Rule.
Upon being notified by a selling stockholder that any material
arrangement has been entered into with a broker-dealer for the sale of shares
through a block trade, special offering, exchange distribution or secondary
distribution or a purchase by a broker or dealer, we will file a supplement
to this Prospectus, if required, pursuant to Rule 424(b) under the Securities
Act, disclosing (i) the name of each such selling stockholder and of the
participating broker-dealer(s), (ii) the number of shares involved, (iii) the
price at which such shares were sold, (iv) the commissions paid or discounts
or concessions allowed to such broker-dealer(s), where applicable, and (v)
other facts material to the transaction. In addition, upon being notified by
a selling stockholder that a donee or pledgee intends to sell more than 500
shares, we will file a supplement to this Prospectus.
WHERE YOU CAN FIND MORE INFORMATION
We file annual, quarterly and special reports, proxy statements and
other information with the Securities and Exchange Commission (SEC). You may
read and copy any document we file at the SEC's public reference room at 450
Fifth Street, N.W., Washington, D.C. 20549. Please call the SEC at
1-800-SEC-0330 for further information on the public reference room. Our SEC
filings are also available to the public from the SEC's Website at "http:
//www.sec.gov."
The SEC allows us to "incorporate by reference" the information we
file with them, which means that we can disclose important information to you
by referring you to those documents. The information incorporated by
reference is considered to be part of this prospectus, and information that
we file later with the SEC will automatically update and supersede this
information. We incorporate by reference the documents listed below and any
future filings we will make with the SEC under Sections 13(a), 13(c), 14 or
15(d) of the Exchange Act:
1. Annual Report on Form 10-K for the fiscal year ended October 3, 1999,
as filed with the SEC on December 30, 1999;
2. Quarterly Report on Form 10-Q for the fiscal quarter ended January
2, 2000, as filed with the SEC on February 16, 2000;
3. Definitive Proxy Statement as filed with the SEC on December 30, 1999,
for the 2000 Annual Meeting of Stockholders; and
4. The description of the Common Stock set forth in the Registration
Statement on Form 8-A dated November 13, 1991, including any
amendments or reports filed for the purpose of updating such
description.
You may request a copy of these filings, at no cost, by writing or
telephoning James M. Jaska as follows:
Tetra Tech, Inc.
Attention: Investor Relations
670 North Rosemead Boulevard
Pasadena, California 91107
(626) 351-4664
This prospectus is part of a registration statement we filed with the
SEC. You should rely only on the information or representations provided in
this prospectus. We have authorized no one to provide you with different
information. We are not making an offer of these securities in any state
where the offer is not permitted. You should not assume that the information
in this prospectus is accurate as of any date other than the date on the
front of the document.
<PAGE>
LEGAL MATTERS
The validity of the Common Stock offered hereby will be passed on for
us by Riordan & McKinzie, a Professional Corporation, Los Angeles,
California. Certain principals of Riordan & McKinzie own shares of Common
Stock.
EXPERTS
The financial statements and the related financial statement schedule
incorporated in this prospectus by reference from our Annual Report on Form
10-K for the year ended October 3, 1999 have been audited by Deloitte &
Touche LLP, independent auditors, as stated in their reports, which are
incorporated herein by reference, and have been so incorporated in reliance
upon the reports of such firm given upon their authority as experts in
accounting and auditing.
