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                                                                    EXHIBIT 3.11

                                     BYLAWS

                                       OF

                        WILLIAMS BROS. CONSTRUCTION, INC.

1)   SHAREHOLDERS' MEETINGS

     .01  ANNUAL MEETINGS

               The annual meeting of the shareholders of this Corporation, for
          the purpose of election of Directors and for such other business as
          may come before it, shall be held at the registered office of the
          Corporation, or such other places, either within or without the State
          of Washington, as may be designated by the notice of the meeting, on
          the FIRST DAY of AUGUST of each and every year, but in case such day
          shall be a legal holiday, the meeting shall be held at the same hour
          and place on the next succeeding day not a holiday.

     .02  SPECIAL MEETINGS

               Special meetings of the shareholders of this Corporation may be
          called at any time by the holders of ten percent (10%) of the voting
          shares of the Corporation, or by the president, or by the Board of
          Directors or a majority thereof. No business shall be transacted at
          any special meeting of shareholders except as is specified in the
          notice calling for said meeting. The Board of Directors may designate
          any place, either within or without the State of Washington, as the
          place of any special meeting called by the president or the Board of
          Directors, and special meetings called at the request of shareholders
          shall be held at such place in Spokane County, Washington, as may be
          determined by the Board of Directors and placed in the notice of such
          meeting.

     .03  NOTICE OF MEETINGS

               Written notice of annual or special meetings of shareholders
          stating the place, day, and hour of the meeting and, in the case of a
          special meeting, the purpose or purposes for which the meeting is
          called shall be given by the secretary or persons authorized to call
          the meeting to each shareholder of record

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          entitled to vote at the meeting. Such notice shall be given not less
          than ten (10) nor more than sixty (60) days prior to the date of the
          meeting, either personally or by mail. If mailed, such notice shall be
          deemed to be delivered when deposited in the United States mail
          addressed to the shareholder at his/her address as it appears on the
          stock transfer books of the Corporation.

     .04  WAIVER OF NOTICE

               Notice of the time, place, and purpose of any meeting may be
          waived in writing and will be waived by any shareholder by his/her
          attendance thereat in person or by proxy. Any shareholder so waiving
          shall be bound by the proceedings of any such meeting in all respects
          as if due notice thereof had been given.

     .05  QUORUM AND ADJOURNED MEETINGS

               A majority of the outstanding shares of the Corporation entitled
          to vote, represented in person or by proxy, shall constitute a quorum
          at a meeting of shareholders. A majority of the shares represented at
          a meeting, even if less than a quorum, may adjourn the meeting from
          time to time without further notice. At such adjourned meeting at
          which a quorum shall be present or represented, any business may be
          transacted which might have been transacted at the meeting as
          originally notified. The shareholders present at a duly organized
          meeting may continue to transact business until adjournment,
          notwithstanding the withdrawal of enough shareholders to leave less
          than a quorum.

     .06  PROXIES

               At all meetings of shareholders, a shareholder may vote by proxy
          executed in writing by the shareholder or by his/her duly authorized
          attorney in fact. Such proxy shall be filed with the secretary of the
          Corporation before or at the time of the meeting. No proxy shall be
          valid after eleven (11) months from the date of its execution, unless
          otherwise provided in the proxy.

     .07  VOTING OF SHARES

               Except as otherwise provided in the Articles of Incorporation or
          in these Bylaws, every shareholder of record shall have the right at
          every shareholders'

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          meeting to one (1) vote for every share standing in his/her name on
          the books of the Corporation, and the affirmative vote of a majority
          of the shares represented at a meeting and entitled to vote thereat
          shall be necessary for the adoption of a motion or for the
          determination of all questions and business which shall come before
          the meeting.

2)   DIRECTORS

     .01  GENERAL POWERS

               The business and affairs of the Corporation shall be managed by
          its Board of Directors.

     .02  NUMBER, TENURE, AND QUALIFICATIONS

               The initial number of Directors of the Corporation shall be three
          (3). However, if the corporation is to have less or more than three
          Directors, the number of Directors to be elected at any annual meeting
          of the shareholders shall be fixed by the shareholders. Each Director
          shall hold office until the next annual meeting of shareholders and
          until his/her successor shall have been elected and qualified.
          Directors need not be residents of the State of Washington or
          shareholders of the Corporation.

     .03  ELECTION

               The Directors shall be elected by the shareholders at their
          annual meeting each year; and if, for any cause, the Directors shall
          not have been elected at an annual meeting, they may be elected at a
          special meeting of shareholders called for that purpose in the manner
          provided by these Bylaws.

     .04  VACANCIES

               In case of any vacancy in the Board of Directors, the remaining
          directors, whether constituting a quorum or not, may elect a successor
          to hold office for the unexpired portion of the term of the Director
          whose place shall be vacant, and until his/her successor shall have
          been duly elected and qualified.

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     .05  RESIGNATION

               Any Director may resign at any time by delivering written notice
          to the secretary of the Corporation.

     .06  MEETINGS

               At any annual, special or regular meeting of the Board of
          Directors, any business may be transacted, and the Board may exercise
          all of its powers. Any such annual, special or regular meeting of the
          Board of Directors of the Corporation may be held outside of the State
          of Washington, and any member or members of the Board of Directors of
          the Corporation may participate in any such meeting by means of a
          conference telephone or similar communications equipment by means of
          which all persons participating in the meeting can hear each other at
          the same time, and participation by such means shall constitute
          presence in person at such meeting.

          A.   ANNUAL MEETINGS OF DIRECTORS

                    Annual meetings of the Board of Directors shall be held
               immediately after the annual shareholders' meeting or at such
               time and place as may be determined by the Directors. No notice
               of the annual meeting of the Board of Directors shall be
               necessary.

          B.   SPECIAL MEETINGS

                    Special meetings of the Directors shall be called at any
               time and place upon the call of the president or any Director.
               Notice of the time and place of each special meeting shall be
               given by the secretary, or the persons calling the meeting, by
               mail, radio, telegram, or by personal communication by telephone
               or otherwise at least three (3) days in advance of the time of
               the meeting. The purpose of the meeting need not be given in the
               notice. Notice of any special meeting may be waived in writing or
               by telegram (either before or after such meeting) and will be
               waived by any Director in attendance at such meeting.

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          C.   REGULAR MEETINGS OF DIRECTORS

                    Regular meetings of the Board of Directors shall be held at
               such place and on such day and hour as shall from time to time be
               fixed by resolution of the Board of Directors. No notice of
               regular meetings of the Board of Directors shall be necessary.

     .07  QUORUM AND VOTING

               A majority of the Directors presently in office shall constitute
          a quorum for all purposes, but a lesser number may adjourn any
          meeting, and the meeting may be held as adjourned without further
          notice. At each meeting of the Board at which a quorum is present, the
          act of a majority of the Directors present at the meeting shall be the
          act of the Board of Directors. The Directors present at a duly
          organized meeting may continue to transact business until adjournment,
          notwithstanding the withdrawal of enough Directors to leave less than
          a quorum.

     .08  COMPENSATION

               By resolution of the Board of Directors, the Directors may be
          paid their expenses if any, of attendance at each meeting of the Board
          of Directors and may be paid a fixed sum for attendance at each
          meeting of the Board of Directors or a stated salary as Director. No
          such payment shall preclude any Director from serving the Corporation
          in any other capacity and receiving compensation therefor.

     .09  PRESUMPTION OF ASSENT

               A Director of the Corporation who is present at a meeting of the
          Board of Directors at which action on any corporate matter is taken
          shall be presumed to have assented to the action taken unless his/her
          dissent shall be entered in the minutes of the meeting or unless
          he/she shall file his/her written dissent to such action with the
          person acting as the secretary of the meeting before the adjournment
          thereof or shall forward such dissent by registered mail to the
          secretary of the Corporation immediately after the adjournment of the
          meeting. Such right to dissent shall not apply to a Director who voted
          in favor of such action.

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     .10  EXECUTIVE AND OTHER COMMITTEES

               The Board of Directors, by resolution adopted by a majority of
          the full Board of Directors, may designate from among its members an
          executive committee and one or more other committees, each of which,
          to the extent provided in such resolution, shall have and may exercise
          all the authority of the Board of Directors, but no such committee
          shall have the authority of the Board of Directors in reference to
          amending the Articles of Incorporation, adopting a plan of merger or
          consolidation, recommending to the shareholders the sale, lease,
          exchange, or other disposition of all or substantially all the
          property and assets of the Corporation otherwise than in the usual and
          regular course of its business, recommending to the shareholders a
          voluntary dissolution of the Corporation or a revocation thereof, or
          amending the Bylaws of the Corporation. The designation of any such
          committee and the delegation thereto of authority shall not operate to
          relieve any member of the Board of Directors of any responsibility
          imposed by law.

     .11  CHAIRMAN OF BOARD OF DIRECTORS

               The Board of Directors may, in its discretion, elect a chairman
          of the Board of Directors from its members and, if a chairman has been
          elected, he/she shall, when present, preside at all meetings of the
          Board of Directors and shareholders and shall have such other powers
          as the Board may prescribe.

3)   ACTIONS BY WRITTEN CONSENT

          Any corporate action required by the Articles of Incorporation,
     Bylaws, or the laws under which this Corporation is formed, to be voted
     upon or approved at a duly called meeting of the Directors and/or
     shareholders may be accomplished without a meeting if unanimous written
     consent of the respective Directors and/or shareholders, setting forth the
     action so taken, shall be signed before taking such action by all the
     Directors and/or shareholders, as the case may be.

4)   OFFICERS

     .01  OFFICERS DESIGNATED

               The Corporation shall designate a president, one or more vice
          presidents (the number thereof to be determined by the Board of
          Directors), and may have a

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          secretary, and a treasurer, each of whom shall be elected by the Board
          of Directors. Such other officers and assistant officers as may be
          deemed necessary may be elected or appointed by the Board of
          Directors. Any two or more offices may be held by the same person,
          except that in the event that the Corporation shall have more than one
          stockholder, the offices of president and secretary shall be held by
          different individuals.

     .02  ELECTION QUALIFICATION, AND TERM OF OFFICE

               Each of the officers shall be elected by the Board of Directors.
          None of said officers, except the president, need be a Director but a
          vice president who is not a Director cannot succeed to or fill the
          office of president. The officers shall be elected by the Board of
          Directors at each annual meeting of the Board of Directors. Except as
          hereinafter provided, each of said officers shall hold office from the
          date of his/her election until the next annual meeting of the Board of
          Directors and until his/her successor shall have been duly elected and
          qualified.

     .03  POWERS AND DUTIES

               The powers and duties of the respective corporate officers shall
          be as follows:

          A.   PRESIDENT

                    The president shall be the chief executive officer of the
               Corporation and, subject to the direction and control of the
               Board of Directors, shall have general charge and supervision
               over its property, business, and affairs. He/she shall, unless a
               chairman of the Board of Directors has been elected and is
               present, preside at meetings of the shareholders and the Board of
               Directors.

          B.   VICE PRESIDENT

                    In the absence of the president or his/her inability to act,
               the senior vice president shall act in his/her place and stead
               and shall have all the powers and authority of the president,
               except as limited by resolution of the Board of Directors.

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          C.   SECRETARY

                    The secretary shall:

               (1)  Keep the minutes of the shareholders' and of the Board of
                    Directors' meetings in one or more books provided for that
                    purpose;

               (2)  See that all notices are duly given in accordance with the
                    provisions of these Bylaws or as required by law;

               (3)  Be custodian of the corporate records and of the seal of the
                    Corporation and affix the seal of the Corporation to all
                    documents as may be required;

               (4)  At all times keep a current record at the registered office
                    or principal place of business of the names and addresses of
                    all shareholders and the number and class of the shares held
                    by each;

               (5)  Sign with the president, or a vice president, certificates
                    for shares of the Corporation, the issuance of which shall
                    have been authorized by resolution of the Board of
                    Directors;

               (6)  Have general charge of the stock transfer books of the
                    Corporation; and

               (7)  In general, to perform all duties incident to the office of
                    secretary and such other duties as from time to time may be
                    assigned to him/her by the president or by the Board of
                    Directors.

          D.   TREASURER

                    Subject to the direction and control of the Board of
               Directors, the treasurer shall have the custody, control, and
               disposition of the funds and securities of the Corporation and
               shall account for the same and, at the expiration of his/her term
               of office, he/she shall turn over to his/her successor all
               property of the Corporation in his/her possession.

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          E.   ASSISTANT SECRETARIES AND ASSISTANT TREASURERS

                    The assistant secretaries, when authorized by the Board of
               Directors, may sign with the president or a vice president
               certificates for shares of the Corporation the issuance of which
               shall have been authorized by a resolution of the Board of
               Directors. The assistant treasurers shall, respectively, if
               required by the Board of Directors, give bonds for the faithful
               discharge of their duties in such sums and with such sureties as
               the Board of Directors shall determine. The assistant secretaries
               and assistant treasurers, in general, shall perform such duties
               as shall be assigned to them by the secretary or the treasurer,
               respectively, or by the president or the Board of Directors.

     .04  REMOVAL

               The Board of Directors shall have the right to remove any officer
          whenever in its judgment the best interest of the Corporation will be
          served thereby.

     .05  VACANCIES

               The Board of Directors shall fill any office which becomes vacant
          with a successor who shall hold office for the unexpired term and
          until his/her successor shall have been duly elected and qualified.

     .06  SALARIES

               The salaries of all officers of the Corporation shall be fixed by
          the Board of Directors.

5)   SHARE CERTIFICATES

     .01  FORM AND EXECUTION OF CERTIFICATES

               Certificates for shares of the Corporation shall be in such form
          as is consistent with the provisions of the Corporation laws of the
          State of Washington. They shall be signed by the president and by the
          secretary, and the seal of the Corporation shall be affixed thereto.
          Certificates may be issued for fractional shares.

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     .02  TRANSFERS

               Shares may be transferred by delivery of the certificates
          therefor, accompanied either by an assignment in writing on the back
          of the certificates or by a written power of attorney to assign and
          transfer the same signed by the record holder of the certificate.
          Except as otherwise specifically provided in these Bylaws, no shares
          shall be transferred on the books of the Corporation until the
          outstanding certificate therefor has been surrendered to the
          Corporation.

     .03  LOSS OR DESTRUCTION OF CERTIFICATES

               In case of loss or destruction of any certificate of shares,
          another may be issued in its place upon proof of such loss or
          destruction, i.e., a sworn affidavit attesting to such loss. A new
          certificate may be issued without requiring a bond of indemnity, when
          in the judgment of the Board of Directors it is proper to do so.

6)   BOOKS AND RECORDS

     .01  BOOKS OF ACCOUNTS, MINUTES, AND SHARE REGISTER

               The Corporation shall keep complete books and records of accounts
          and minutes of the proceedings of the Board of Directors and
          shareholders and shall keep at its registered office, principal place
          of business, or at the office of its transfer agent or registrar a
          share register giving the names of the shareholders in alphabetical
          order and showing their respective addresses and the number and class
          of shares held by each.

     .02  COPIES OF RESOLUTIONS

               Any person dealing with the Corporation may rely upon a copy of
          any of the records of the proceedings, resolutions, or votes of the
          Board of Directors or shareholders, when certified by the president or
          secretary.

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7)   CORPORATE SEAL

          The following is an impression of the corporate seal of this
     Corporation:


8)   LOANS

          No loans shall be made by the Corporation to its officers or
     Directors, unless first approved by the holders of two-thirds of the voting
     shares or the Board of Directors determines that the loan benefits the
     corporation and thereby approves the loan. No loans shall be made by the
     Corporation secured by its shares.

9)   INDEMNIFICATION OF DIRECTORS AND OFFICERS

          Each Director or officer now or hereafter serving the Corporation, and
     each person who at the request of or on behalf of the Corporation is now
     serving or hereafter serves as Director or officer of any other corporation
     and the respective heirs, executors, and administrators of each of them
     shall be indemnified by the Corporation to the fullest extent provided by
     law against all costs, expenses, judgments, and liabilities, including
     attorneys' fees, reasonably incurred by or imposed upon him in connection
     with or resulting from any claim, action, suit, or proceeding, civil or
     criminal, in which he/she is or may be made a party by reason of his/her
     being or having been such Director or officer by reason of any action
     alleged to have been taken or omitted by him/her as such Director or
     officer, whether or not he/she is a Director or officer at the time of
     incurring such costs, expenses, judgments, and liabilities, provided that
     he/she acted in good faith and in a manner he/she reasonably believed to be
     in or not opposed to the best interests of the Corporation. The termination
     of any action, suit, or proceeding by judgment, order, settlement, or
     conviction or upon a plea of nolo contendere or its equivalent shall not,
     of itself, create a presumption that the person did not act in good faith
     and in a manner which he reasonably believed to be in or not opposed to the
     best interests of the Corporation. The foregoing right of indemnification

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     shall not be exclusive of other rights to which such Director or officer
     may be entitled as a matter of law. The Board of Directors may obtain
     insurance on behalf of any person who is or was a director, officer,
     employee, or agent against any liability arising out of his/her status as
     such, whether or not the Corporation would have power to indemnify him/her
     against such liability.

10)  AMENDMENT OF BYLAWS

     .01  BY THE SHAREHOLDERS

               These Bylaws may be amended, altered, or repealed at any regular
          or special meeting of the shareholders if notice of the proposed
          alteration or amendment is contained in the notice of the meeting.

     .02  BY THE BOARD OF DIRECTORS

               These Bylaws may be amended, altered, or repealed by the
          affirmative vote of a majority of the whole Board of Directors at any
          regular or special meeting of the Board.

11)  FISCAL YEAR

          The fiscal year of the Corporation shall be set by resolution of the
     Board of Directors.

12)  RULES OF ORDER

          The rules contained in the most recent edition of Robert's Rules of
     Order, Newly Revised, shall govern all meetings of shareholders and
     Directors where those rules are not inconsistent with the Articles of
     Incorporation, Bylaws, or special rules of order of the Corporation.

13)  REIMBURSEMENT OF DISALLOWED EXPENSES

          If any salary, payment, reimbursement, employee fringe benefit,
     expense allowance payments, or other expense incurred by the Corporation
     for the benefit of an employee is disallowed in whole or in part as a
     deductible expense of the Corporation for Federal Income Tax purposes, the
     employee shall reimburse the Corporation, upon notice and demand, to the
     full extent of the disallowance. This legally enforceable obligation is in
     accordance with the provisions of Revenue Ruling 69-115, 1969-1 C.B. 50,
     and is for the purpose of entitling such employee to a business expense
     deduction for the taxable year in which the repayment is made to the
     Corporation.

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     In this manner, the Corporation shall be protected from having to bear the
     entire burden of any disallowed expense item.

                            C E R T I F I C A T I O N

     The undersigned secretary for WILLIAMS BROS. CONSTRUCTION, INC., a
Washington corporation, hereby certifies that on the _________ day of June,
1992, the attached Bylaws consisting of 13 pages were presented and adopted by
the Corporation at the First Meeting of the Board of Directors.

                                         /s/ Gerald R. Williams
                                         ---------------------------------------
                                         Secretary

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