EXECUTION COPY



                         STOCKHOLDERS SUPPORT AGREEMENT

     STOCKHOLDERS AGREEMENT, dated as of April 14, 2005 (this "AGREEMENT"),
among Stantec Inc., a Canadian corporation ("PARENT"), Stantec Consulting
California Inc., a California corporation and a wholly owned subsidiary of
Parent ("PURCHASER"), and each of the stockholders whose names appear on Exhibit
A to this Agreement (each, a "STOCKHOLDER" and, collectively, the
"STOCKHOLDERS").

     WHEREAS, as of the date hereof and except as noted on Exhibit A hereto,
each Stockholder represents and warrants to Parent that he, she or it owns of
record and/or beneficially and has good, valid and marketable title to, free and
clear of any Lien, proxy, voting restriction, limitation on disposition, adverse
claim of ownership or use or encumbrance of any kind, other than pursuant to
this Agreement, a margin account established in accordance with Regulation T
under the Securities Exchange Act of 1934, as amended, the trust agreement
establishing the Aram H. Keith and Margie R. Keith Revocable Trust dated October
23, 1989 (the "TRUST"), and the Trust has the sole power to vote the number of
shares of common stock, par value $0.001 per share ("Company Common Stock"), of
The Keith Companies, Inc., a California corporation (the "Company"), as set
forth opposite such Stockholder's name on Exhibit A hereto (all such shares of
Company Common Stock and any shares of Company Common Stock of which ownership
of record or the power to vote is hereafter acquired by the Stockholders prior
to the termination of this Agreement being referred to herein as the "Shares");
and

     WHEREAS, Parent, Purchaser and the Company propose to enter into,
simultaneously herewith, an Agreement and Plan of Merger and Reorganization (the
"Merger Agreement"; terms used but not defined in this Agreement shall have the
meanings ascribed to them in the Merger Agreement), a draft of which has been
made available to each Stockholder, which provides, upon the terms and subject
to the conditions thereof, for the merger of Purchaser with and into the Company
(the "Merger");

     NOW, THEREFORE, in consideration of the foregoing and of the mutual
covenants and agreements contained herein and in the Merger Agreement, and
intending to be legally bound hereby, the Stockholders hereby agree as follows:

     1.   REPRESENTATIONS AND WARRANTIES OF THE STOCKHOLDERS. Each Stockholder
          hereby, jointly and severally, represents and warrants to Parent and
          Purchaser as follows:

          (a)  The Trust is a trust duly organized, validly existing and in good
               standing under the laws of the State of California. The Trust has
               all necessary power and authority to execute and deliver this
               Agreement and to perform its obligations hereunder. The execution
               and delivery of this Agreement by the Trust and the performance
               by the Trust of its obligations hereunder have been duly and
               validly authorized by all necessary action, and no other
               proceedings on the part of the Trust are necessary to authorize
               this Agreement or to perform its obligations hereunder. This
               Agreement has been duly executed and delivered by the Trust and,
               assuming the due authorization, execution and delivery by Parent
               and Purchaser, constitutes the legal, valid and binding
               obligation of the Trust, enforceable against the Trust in
               accordance with its terms, except as such enforceability may be
               limited by applicable bankruptcy insolvency and similar laws
               affecting creditors' rights generally and general principles of
               equity (whether considered in a proceeding at law or equity).

          (b)  The execution and delivery of this Agreement by the Trust do not,
               and the performance of this Agreement by the Trust will not, (A)
               conflict with or violate the organizational documents of the
               Trust, (B) assuming that all consents, approvals, authorizations
               and other actions described in subsection (c) have been obtained
               and all filings and obligations described in subsection (c) have
               been made, conflict with or violate any Law applicable to the
               Trust or by which any property or asset of the Trust is bound or
               affected, or (C) result in any breach of or constitute a default
               (or an event which, with notice or lapse of time or both, would
               become a default) under, or give to others any right of
               termination, amendment, acceleration or cancellation of, or
               result in the creation of a Lien or other





               encumbrance on any property or asset of the Trust pursuant to,
               any note, bond, mortgage, indenture, contract, agreement, lease,
               license, permit, franchise or other instrument or obligation.

          (c)  The execution and delivery of this Agreement by each Stockholder
               does not, and the performance of this Agreement by each
               Stockholder will not, require any consent, approval,
               authorization or permit of, or filing with or notification to,
               any Governmental Authority, except for applicable requirements,
               if any, of the Securities Act of 1933, as amended, the Exchange
               Act and the HSR Act.

          (d)  With respect to Aram H. Keith and Margie R. Keith (each an
               "INDIVIDUAL"), this Agreement has been duly executed and
               delivered by each Individual and, assuming the due authorization,
               execution and delivery by Parent and Purchaser, constitutes the
               legal, valid and binding obligation of each Individual,
               enforceable against each Individual in accordance with its terms,
               except as such enforceability may be limited by applicable
               bankruptcy insolvency and similar laws affecting creditors'
               rights generally and general principles of equity (whether
               considered in a proceeding at law or equity).

          (e)  Except for shares of Company Common Stock held directly by the
               Trust, the Individuals do not own, either directly or
               beneficially, any shares of Company Common Stock.

     2.   GRANT OF PROXY. Each Stockholder, by this Agreement, with respect to
          his, her or its Shares, hereby agrees, and to secure such agreement,
          grants an irrevocable proxy to Parent (and agrees to execute such
          documents or certificates evidencing such proxy as Parent may
          reasonably request) to vote, at any meeting of the stockholders of the
          Company, and in any action by written consent of the stockholders of
          the Company, all of such Stockholder's Shares (i) in favor of the
          approval and adoption of the Merger Agreement and approval of the
          Merger, (ii) against any action, agreement or transaction (other than
          the Merger Agreement or the Merger) or proposal (including any
          Superior Proposal) that would result in a breach of any covenant,
          representation or warranty or any other obligation or agreement of the
          Company under the Merger Agreement or that could result in any of the
          conditions to the Company's obligations under the Merger Agreement not
          being fulfilled, and (iii) in favor of any other matter necessary to
          the consummation of the Merger and considered and voted upon by the
          stockholders of the Company. Each Stockholder further agrees to cause
          such Stockholder's Shares to be voted in accordance with the
          foregoing. THIS PROXY IS IRREVOCABLE AND SECURES THE PERFORMANCE BY
          THE STOCKHOLDERS OF THE DUTIES SET FORTH HEREIN. Each Stockholder
          acknowledges receipt and review of a copy of the Merger Agreement.

     3.   TRANSFER OF SHARES. Each Stockholder agrees that he, she or it shall
          not, directly or indirectly, (a) sell, assign, transfer (including by
          operation of law), lien, pledge, dispose of or otherwise encumber any
          of the Shares or otherwise agree to do any of the foregoing, (b)
          deposit any Shares into a voting trust or enter into a voting
          agreement or arrangement or grant any proxy or power of attorney with
          respect thereto that is inconsistent with this Agreement, (c) enter
          into any contract, option or other arrangement or undertaking with
          respect to the direct or indirect acquisition or sale, assignment,
          transfer (including by operation of law) or other disposition of any
          Shares or (d) take any action that would make any representation or
          warranty of such Stockholder herein untrue or incorrect in any
          material respect or have the effect of preventing or disabling the
          Stockholder from performing his, her or its obligations hereunder.

     4.   NO SOLICITATION OF TRANSACTIONS. None of the Stockholders shall,
          directly or indirectly, (a) solicit, initiate or encourage the
          submission of, any Competing Transaction or (b) participate in any
          discussions or negotiations regarding, or furnish to any person, any
          information with respect to, or otherwise cooperate in any way with
          respect to, or assist or participate in, facilitate or encourage, any
          unsolicited proposal that constitutes, or may reasonably be expected
          to lead to, a Superior Proposal; PROVIDED, however, that nothing in
          this Section 3 shall prevent Aram H. Keith, in his capacity as a
          director and executive officer of the Company from, engaging in any
          activity permitted pursuant to Section 6.04 of the Merger Agreement.
          Each Stockholder shall, and shall direct his, her or its
          representatives and agents to, immediately cease and terminate any
          discussions or negotiations with any parties that may be ongoing with
          respect to any Competing Transaction.

     5.   INFORMATION FOR PROXY STATEMENT/PROSPECTUS; DISCLOSURE. Each
          Stockholder authorizes and agrees to permit Parent and Purchaser to
          publish and disclose in the Proxy




          Statement/Prospectus and related filings under the securities laws
          such Stockholder's identity and ownership of Shares and the nature of
          his, her or its commitments, arrangements and understandings under
          this Agreement and any other information required by applicable Law.

     6.   TERMINATION. The obligations of the Stockholders under this Agreement
          shall terminate upon the earlier of (i) the Effective Time and (ii)
          upon the termination of the Merger Agreement. Nothing in this Section
          7 shall relieve any party of liability for any breach of this
          Agreement occurring prior to the time of such termination.

     7.   MISCELLANEOUS. Notwithstanding anything to the contrary contained
          herein, no action of a Stockholder in his, her or its capacity as a
          director or executive officer of the Company shall constitute a breach
          of this Agreement. Except as otherwise provided herein, all costs and
          expenses incurred in connection with this Agreement and the
          transactions contemplated hereby shall be paid by the party incurring
          such costs and expenses, whether or not the transactions contemplated
          hereby are consummated; all notices, requests, claims, demands and
          other communications hereunder shall be in writing and shall be given
          (and shall be deemed to have been duly given upon receipt) by delivery
          in person, by telecopy, e-mail or by registered or certified mail
          (postage prepaid, return receipt requested) to the respective parties
          at their addresses as specified on the signature page(s) of this
          Agreement; if any term or other provision of this Agreement is
          invalid, illegal or incapable of being enforced by any rule of law or
          public policy, all other conditions and provisions of this Agreement
          shall nevertheless remain in full force and effect so long as the
          economic or legal substance of the transactions contemplated hereby is
          not affected in any manner materially adverse to any party; this
          Agreement and the Merger Agreement constitute the entire agreement
          among the parties with respect to the subject matter hereof and
          supersede all prior agreements and undertakings, both written and
          oral, among the parties, or any of them, with respect to the subject
          matter hereof; this Agreement shall not be assigned (whether pursuant
          to a merger, by operation of law or otherwise), except that Parent may
          assign all or any of its rights and obligations hereunder to any
          affiliate of Parent, PROVIDED, HOWEVER, that no such assignment shall
          relieve the assigning party of its obligations hereunder if such
          assignee does not perform such obligations; this Agreement shall be
          binding upon and inure solely to the benefit of each party hereto, and
          nothing in this Agreement, express or implied, is intended to or shall
          confer upon any other person any right, benefit or remedy of any
          nature whatsoever under or by reason of this Agreement; the parties
          hereto agree that irreparable damage would occur in the event any
          provision of this Agreement was not performed in accordance with the
          terms hereof and that the parties shall be entitled to specific
          performance of the terms hereof, in addition to any other remedy at
          law or in equity; this Agreement shall be governed by, and construed
          in accordance with, the laws of the State of California applicable to
          contracts executed in and to be performed in that State; this
          Agreement may be executed and delivered (including by facsimile
          transmission) in one or more counterparts, and by the different
          parties hereto in separate counterparts, each of which when executed
          shall be deemed to be an original but all of which taken together
          shall constitute one and the same agreement; from time to time, at the
          request of Parent, in the case of any Stockholder, or at the request
          of the Stockholders, in the case of Parent and Purchaser, and without
          further consideration, each party shall execute and deliver or cause
          to be executed and delivered such additional documents and instruments
          and take all such further action as may be reasonably necessary or
          desirable to give effect to the rights, duties and obligations of the
          parties set forth in this Agreement; EACH OF THE PARTIES HERETO HEREBY
          WAIVES TO THE FULLEST EXTENT PERMITTED BY APPLICABLE LAW ANY RIGHT IT
          MAY HAVE TO A TRIAL BY JURY WITH RESPECT TO ANY LITIGATION DIRECTLY OR
          INDIRECTLY ARISING OUT OF, UNDER OR IN CONNECTION WITH THIS AGREEMENT.




     IN WITNESS WHEREOF, the parties have executed this Agreement as of the date
first written above.


                    STANTEC INC.



                    By /s/  Anthony P. Franceschini
                       -----------------------------------------------
                       Name:  Anthony P. Franceschini
                       Title: President & CEO



                    By /s/ Jeffrey S. Lloyd
                       -----------------------------------------------
                       Name:  Jeffrey S. Lloyd
                       Title: Vice President, Secretary &
                              General Counsel



                    STANTEC CONSULTING CALIFORNIA INC.



                    By /s/ Anthony P. Franceschini
                       -----------------------------------------------
                       Name:  Anthony P. Franceschini
                       Title: President



                    By /s/ Michael J. Slocombe
                       -----------------------------------------------
                       Name:  Michael J. Slocombe
                       Title: Secretary



                    ARAM H. KEITH AND MARGIE R. KEITH
                    REVOCABLE TRUST


                    By /s/ Aram H. Keith
                       -----------------------------------------------
                       Name:  Aram H. Keith, as Trustee



                    By: /s/ Margie R. Keith, as Trustee
                        ----------------------------------------------
                        Margie R. Keith, as Trustee



                        /s/ Aram H. Keith
                        ----------------------------------------------
                        Aram H. Keith



                        /s/ Margie R. Keith
                        ----------------------------------------------
                        Margie R. Keith








                                    EXHIBIT A

                              LIST OF STOCKHOLDERS


                                                     Number of Shares of Company
                                                          Common Stock Owned
             NAME OF STOCKHOLDER                     BENEFICIALLY AND OF RECORD
             -------------------                     ---------------------------
ARAM H. KEITH AND MARGIE R. KEITH REVOCABLE
TRUST DATED OCTOBER 23, 1989................                  1,366,217

ARAM H. KEITH...............................                  1,366,217

MARGIE R. KEITH.............................                  1,366,217