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                                                                    EXHIBIT 10.1

                             PITT-DES MOINES, INC.
                              LONG TERM INCENTIVE
                               STOCK PLAN OF 1997
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     Section 1.  Purpose.  This plan is to be known as the Pitt-Des Moines, Inc.
Long Term Incentive Stock Plan of 1997 (the "Plan").  The purpose of the Plan is
to promote the long-term growth and profitability of Pitt-Des Moines, Inc. (the
"Company") and its Subsidiaries by: (a) providing certain officers and key
employees of the Company and its Subsidiaries with incentives to maximize
stockholder value and otherwise contribute to the success of the Company; and
(b) enabling the Company to attract, retain and reward the best available
persons for positions of substantial responsibility.  Grants of nonqualified
stock options and restricted stock may be made under the Plan.

     Section 2.  Administration.  The Plan is to be administered by a committee
(hereinafter the "Committee") of not less than three directors of the Company
who will be appointed by, and serve at the pleasure of, the Board of Directors.
A majority of the Committee constitutes a quorum and the acts of a majority of
the members present at any meeting at which a quorum is present, or acts
approved in writing by a majority of the Committee, are deemed to be acts of the
Committee.  Subject to the provisions of the Plan and to policies determined by
the Board of Directors, the Committee is authorized to interpret the Plan, adopt
rules and regulations and to take any action it deems proper in the
administration of the Plan.

     Section 3.  Shares Available for the Plan.  Subject to adjustments as
provided in Section 10, an aggregate of 700,000 shares of the Company's common
stock ("Shares") may be issued pursuant to the Plan.  Shares may be in whole or
in part authorized and unissued, or Shares which have been reacquired by the
Company and Shares held as treasury shares.  If any grant under the Plan expires
or terminates unexercised, becomes unexercisable or is forfeited as to any
Shares, such unpurchased or forfeited Shares shall be available for further
grants under the Plan.  There shall also be added to the Shares available for
grant under the Plan any Shares delivered to or withheld by the Company in
payment of the exercise price or for taxes, and any Shares acquired in the open
market specifically for use in the Plan.

     Section 4.  Participation.  Participation in the Plan shall be limited to
those officers and key employees of the Company and its Subsidiaries as may be
selected by the Committee.  Nothing in the Plan or in any grant thereunder shall
confer any right on a participant to continue in the employ of the Company.
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     Section 5.  Nonqualified Stock Options.  The Committee may from time to
time grant to eligible participants Nonqualified Stock Options.  The options
granted shall take such form as the Committee shall determine, subject to the
following terms and conditions.

     (a)  Price. The price per Share deliverable upon the exercise of each
          option ("Exercise Price") shall be the Fair Market Value of a Share on
          the relevant date as determined by the Committee.

     (b)  Payment.

          (i)  Options may be exercised, in whole or in part, upon payment of 
               the Exercise Price of the Shares to be acquired. Unless otherwise
               determined by the Committee, payment shall be made: (A) in cash;
               (B) by delivery of outstanding Shares with a Fair Market Value on
               the date of exercise equal to the aggregate exercise price
               payable with respect to the option(s) being exercised; (C) by
               delivering to the Company a notice of exercise along with
               irrevocable instructions to a broker, registered under the
               Securities Exchange Act of 1934, as amended (the "Exchange Act")
               and reasonably acceptable to the Company, to sell a sufficient
               number of Shares to pay the Exercise Price of the Shares acquired
               and to remit the proceeds directly to the Company; (D) by
               authorizing the Company to withhold from issuance a number of
               Shares issuable upon exercise of the options which, when
               multiplied by the Fair Market Value of a Share on the date of
               exercise, is equal to the aggregate exercise price payable with
               respect to the options so exercised; or (E) by any combination of
               the foregoing.

          (ii) In the event an optionee elects to pay the exercise price 
               payable with respect to an option pursuant to clause (i)(B)
               above: only a whole number of Share(s) may be tendered in
               payment; and such grantee must present evidence acceptable to the
               Company that he or she has owned such Shares so tendered, and
               that such tendered Shares have not been subject to any
               substantial risk of forfeiture for at least six months prior to
               the date of exercise. Delivery may be made either by physical
               delivery of the certificate(s) for all such Shares tendered,
               accompanied by duly executed instruments of transfer in form
               acceptable to the Company, or by direction to the grantee's
               broker to transfer such shares to a brokerage account specified
               by the Company. When payment of the exercise price is made by
               delivery of Shares, the difference, if any, between the aggregate
               exercise price payable with respect to the option(s) being
               exercised and the Fair Market Value of the Share(s) tendered
               (plus any applicable taxes) shall be paid in cash. No optionee
               may tender Shares having 
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               a Fair Market Value exceeding the aggregate exercise price (plus
               any applicable taxes) payable with respect to the option being
               exercised.

         (iii) In the event an optionee elects to pay the exercise price payable
               pursuant to clause (i)(D) above: only a whole number of Share(s)
               may be withheld; and optionee must present evidence acceptable to
               the Company that he or she has owned a number of Shares at least
               equal to the number of Shares to be withheld, and that such
               Shares have not been subject to any substantial risk of
               forfeiture for at least six months prior to the date of exercise.
               When payment of the exercise price is made by withholding of
               Shares, the difference, if any, between the aggregate exercise
               price payable with respect to the option being exercised and the
               Fair Market Value of the Share(s) withheld in payment (plus any
               applicable taxes) shall be paid in cash. No optionee may
               authorize the withholding of Shares having a Fair Market Value
               exceeding the aggregate exercise price (plus any applicable
               taxes) payable with respect to the option being exercised. Any
               withheld Shares shall no longer be issuable under any option.

          (iv) In the event of a Change in Control, in lieu of any payment 
               election pursuant to clause (i) above, an optionee shall have the
               right, upon exercise, to surrender the right to receive that
               number of Shares which are subject to the option being exercised,
               in exchange for the Company's payment in cash of the difference
               between the Fair Market Value of the Shares so surrendered on the
               date the option is exercised and the Exercise Price, less any
               withholding elected or required pursuant to Section 13 of the
               Plan.

     (c)  Terms of Options.  The term during which each option may be exercised
          shall be determined by the Committee, but in no event shall an option
          be exercisable in whole or in part more than ten years from the date
          it is granted. All rights to purchase Shares pursuant to an option
          shall, unless sooner terminated, expire at the date designed by the
          Committee. The Committee shall determine the date on which each option
          shall become exercisable and may provide that an option shall become
          exercisable in installments.

     Section 6.  Exercise and Conditions of Options.

     (a)  During the lifetime of the optionee, options under the Plan may be
          exercised only by the optionee, by his or her guardian or legal
          representative or pursuant to a valid and enforceable qualified
          domestic relations order. Options shall not be transferrable otherwise
          than by will or by the laws of descent and distribution, except that
          the Committee may permit transfer upon the optionee's death to
          beneficiaries designated 
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          by the optionee in a form and manner authorized by the Company,
          provided that the Company determines that such exercise and such
          transfer are consonant with any requirements for exemption from
          Section 16(b) of the Exchange Act, the Securities Act of 1933 as
          amended (the "Securities Act") and any other applicable law.

     (b)  An option may be exercised within such period or periods or on such
          specific date or dates as may be determined by the Committee and set
          forth in the stock option agreement provided that:

          (i)  if the optionee ceases to be employed by the Company or any of 
               its Subsidiaries for any reason other than Deferred Retirement,
               Normal Retirement, Early Retirement, death or disability, the
               option may be exercised only within ninety (90) days after the
               termination of the optionee's employment, unless such termination
               is for Cause as defined in Section 15 hereof or constitutes a
               breach by the employee of his or her obligation to remain in the
               employ of the Company or a Subsidiary, in which case the option
               shall terminate immediately upon such termination;

          (ii) if the optionee dies or becomes disabled, the option may be 
               exercised within one (1) year from the date of death or
               disability;

        (iii)  if the optionee takes Early Retirement, the option may be 
               exercised within one (1) year from the optionee's Early
               Retirement Date; and

          (iv) if the optionee takes Deferred Retirement or Normal Retirement,
               the option may be exercised within three (3) years from the
               optionee's Deferred Retirement Date or Normal Retirement Date, as
               applicable.

     (c)  In the event there is a Change in Control of the Company, all of a
          participant's options previously granted under the Plan shall vest and
          become immediately exercisable effective upon the date of such Change
          in Control.

     (d)  Options may be exercised only by written request to the Secretary of
          the Company at the principal office of the Company, prior to the
          expiration of the option, accompanied by payment as described in
          Section 5(b) above. The certificate for the Shares purchased by such
          exercise shall be issued and delivered to the person entitled thereto
          at the principal office of the Company.

     (e)  In consideration for the granting of each option, the optionee shall
          agree to remain in the employ of the Company or any of its
          Subsidiaries, at the pleasure of the Company or such Subsidiaries, for
          at least one year from the date of grant of such option at his
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          or her salary rate in effect at the time of the grant of the option or
          at such increased rate as may be fixed from time to time by the
          Company or its Subsidiaries. At the discretion of the Committee, this
          requirement may be waived in the case of any optionee who during the
          said one-year period enters the active services of the military forces
          of the United States or other United States government service
          connected with national defense activities.


     Section 7.  Restricted Stock.  The Committee may at any time and from time
to time grant Shares of restricted stock under the Plan to such participants and
in such amounts as it determines.  Each grant of restricted stock shall specify
the applicable restrictions on such Shares, the duration of such restrictions
and the time or times at which such restrictions shall lapse with respect to all
or a specified number of Shares that are part of the grant, provided, however,
that in no event shall any grant of restricted stock vest more than ten years
from the date of its issuance.  The participant will not be required to pay the
Company any consideration upon the initial issuance of any Shares of restricted
stock under the Plan.   The Shares will be held by the Company on the
participant's behalf during any period of restriction thereon and will bear an
appropriate legend specifying the applicable restrictions.  Except as otherwise
provided by the Committee, during such period of restriction the participant
shall have all of the rights of a holder of Shares, including but not limited to
the rights to receive dividends (or amounts equivalent to dividends) and to
vote.  Any stock received as a dividend or distribution with respect to a
participant's restricted stock shall be subject to the same restrictions as then
in effect for the restricted stock.

     Section 8.  Vesting and Conditions of Grants and Company's Repurchases of
Restricted Stock.

     (a)  During the lifetime of the grantee of restricted stock under the Plan,
          Shares so granted shall vest in accordance with the terms of any grant
          pursuant to Section 7 and, prior to vesting, such Shares shall not be
          transferable.

     (b)  If a participant holds restricted stock under the Plan which has not
          vested on the date he or she ceases to be employed by the Company for
          any reason, such restricted stock shall revert to the Company on the
          date of such termination of employment.

     (c)  In the event there is a Change in Control of the Company, all of a
          participant's restricted stock previously issued, but not then vested,
          shall vest immediately, effective upon the date of such Change in
          Control.
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     (d)  The Company may, in any agreement with a participant entered into
          pursuant to this Plan, agree to purchase any shares of restricted
          stock previously issued to such participant, effective with any Change
          in Control.

     Section 9.  Authority of Committee.  Subject to the provisions of the Plan,
the Committee shall have full and final authority to determine the persons to
whom options and restricted stock may be awarded and the number of shares to be
covered by each grant or option.  The Committee may include such other terms and
conditions not inconsistent with the foregoing as the Committee shall determine
for any or all stock option agreements and agreements granting restricted stock,
including conditions based on the performance of the Company or a portion of the
Company, conditions based on the performance of the participant, or conditions
based on a combination thereof.  The Committee's determinations under the Plan,
including without limitation determination of the persons to receive restricted
stock or options, the terms and provisions of such grants and options and the
agreements evidencing all of same, need not be uniform and may be made
selectively among persons who receive, or are eligible to receive, restricted
stock or options under the Plan, whether or not such persons are similarly
situated.  The Committee, in its sole discretion, may permit an optionee
voluntarily to surrender for cancellation an option granted under the Plan, such
surrender to be conditioned upon the granting of such optionee of a new option
under the Plan for the same or a different number of shares as the option
surrendered, or may require such voluntary surrender as a condition precedent to
the grant of a new option to such optionee.

     Section 10.  Adjustment of Number and Price of Shares.

     (a)  In the event that a dividend is declared upon Shares and is payable in
          Shares, the number of Shares covered by each outstanding option, the
          number of Shares of previously issued restricted stock and the number
          of Shares available for issuance pursuant to the Plan but not yet
          covered by an option or issued as restricted stock shall be adjusted
          by adding thereto the number of Shares which would have been
          distributable thereon if such Shares had been outstanding on the date
          fixed for determining the shareholders entitled to receive the stock
          dividend.

     (b)  In the event that the outstanding Shares are changed into or exchanged
          for a different number or kind of shares of stock or other securities
          of the Company or of another company, whether through reorganization,
          recapitalization, stock split-up, combination of shares, merger or
          consolidation, there shall be substituted for the Shares covered by
          each outstanding option, the shares issued as restricted stock and for
          the Shares available for issuance pursuant to the Plan but not yet
          covered by an option or issued as restricted stock, the number and
          kind of shares of stock or other securities which would have been
          substituted therefore if such Shares had been 
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          outstanding on the date fixed for determining the shareholders
          entitled to receive such changed or substituted stock or other
          securities.

     (c)  In the event there is any change, other than specified above in
          Section 10(a) or (b), in the number and kind of outstanding Shares or
          of any stock or other securities into which such Shares shall be
          changed or for which it shall have been exchanged and such change
          equitably requires adjustment in the number or kind of Shares covered
          by outstanding options, the Shares issued as restricted stock or which
          are available for issuance pursuant to the Plan, such adjustment shall
          be made by the Committee and shall be effective and binding for all
          purposes of the Plan and on each outstanding stock option agreement
          and each agreement concerning restricted stock.

     (d)  In the case of any adjustment or substitution provided for in this
          Section 10, the option price per Share in each stock option agreement
          shall be equitably adjusted to reflect the greater or lesser number of
          shares of stock or other securities into which the stock covered by
          the option may have been changed or which may have been substituted
          therefore.

     (e)  No adjustment or substitution provided for in this Section 10 shall
          require the Company to issue or to sell a fractional share and the
          total adjustment or substitution shall be limited accordingly.

     Section 11.  Amendment and Discontinuance.  Subject to applicable law and
the rules, regulations and requirements of any exchange or market on which the
Shares are listed or traded, the Board of Directors may alter, amend, suspend or
discontinue the Plan, provided that no such action shall deprive any person,
without such person's consent, of any rights previously granted pursuant hereto.

     Section 12.  Compliance with Governmental Regulations.  Notwithstanding any
provision of the Plan or the terms of any agreement issued under the Plan, the
Company shall not be required to issue any shares hereunder prior to
registration of the shares subject to the Plan under the Securities Act, the
Exchange Act and any qualification or listing of the Shares with any exchange or
market on which the Shares are listed or traded, if such registration shall be
necessary, or before compliance by the Company or any participant with any other
provisions of either of those acts or of regulations or rulings of the
Securities and Exchange Commission thereunder, or before compliance with all
other applicable Federal and State laws and regulations and rulings thereunder.
After the approval of this Plan by the stockholders of the Company pursuant to
Section 14, the Company shall use its best efforts to effect such registrations
and to comply with such laws, regulations and rulings forthwith upon advice by
its counsel that any such registration or compliance is necessary.
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     Section 13.  Withholding.
 
     (a)  Whenever Shares are to be issued or become vested under the Plan, the
          Company shall have the right to require the participant to remit to
          the Company an amount sufficient to satisfy any Federal, State and
          local tax withholding requirements.

     (b)  In the event that any withholding is required pursuant to Section
          13(a), or is to be made at the participant's election upon issuance or
          vesting of Shares under the Plan, the Company may agree to withhold
          such number of Shares to be issued or become vested with a Fair Market
          Value equal to or less than the amount to be withheld and remit in
          cash the Fair Market Value of Shares so withheld to satisfy any such
          tax withholding requirements.

     Section 14.  Effective Date, Term of Plan.  This Plan shall become
effective as of November 6, 1997, contingent upon the Plan being approved by
vote of the stockholders of the Company on or before October 31, 1998.  In the
event that said approval is not obtained, this Plan, and any agreement entered
into pursuant thereto, shall become void and of no effect.  This Plan shall
terminate in any event on November 1, 2007.

     Section 15.  Definitions.  For purposes of this Plan and any stock options
or restricted stock granted hereunder, or any agreements relating thereto, the
following capitalized terms shall have the meanings ascribed below:

     (a)  Cause shall mean:

          (i)    any act or omission by the optionee which constitutes a felony
                 or misdemeanor, or involves dishonesty or serious disloyalty;

          (ii)   any act or omission which is an intentional violation of the
                 written policies of the Company;

          (iii)  any act or omission which constitutes failure by the optionee
                 to perform diligently and competently optionee's duties; or

          (iv)   any willful or grossly negligent act or omission which has a
                 material adverse effect on the Company's reputation, business
                 affairs or goodwill.

     (b)  Change in Control shall mean
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          (i)    the acquisition by any person, entity or group (within the
                 meaning of Section 13(d)(3) or 14(d)(2) of the Securities
                 Exchange Act of 1934, as amended (the "Exchange Act")) (a
                 "Person"), other than the Company, any of its Subsidiaries or
                 any employee benefit plan of the Company or its Subsidiaries,
                 of beneficial ownership (within the meaning of Rule 13d-3
                 promulgated under the Exchange Act) of 40% or more of either
                 the then outstanding shares of common stock or the combined
                 voting power of the Company's then outstanding voting
                 securities entitled to vote generally in the election of
                 directors ("Voting Securities");

          (ii)   Any change or changes in the composition of the Board for
                 reasons other than the death, disability, normal retirement or
                 unsolicited resignation of directors which change or changes
                 occur during any 24 month period and result in the individuals
                 who constituted the Board at the beginning of the applicable 24
                 month period ceasing to constitute a majority of the Board;

          (iii)  A merger or consolidation to which the Company is a party;
                 provided, however, that such a merger or consolidation shall
                 not be deemed to be a Change in Control if after giving effect
                 to such merger or consolidation, (A) the persons who were the
                 shareholders of the Company immediately prior to such
                 transaction are, immediately thereafter, the owners of more
                 than 50% of the combined voting power entitled to vote
                 generally in the election of directors of the merged or
                 consolidated company's then outstanding securities and (B) no
                 Person (other than any Person beneficially owning, immediately
                 prior to such merger or consolidation, 20% or more of the
                 Voting Securities of the Company and whose ownership interest
                 in the merged or consolidated company's securities was derived
                 solely by virtue of the exchange or conversion of such Voting
                 Securities) owns more than 20% of the combined voting power
                 entitled to vote generally in the election of directors of the
                 merged or consolidated company's then outstanding securities.

          (iv)   The sale of all or Substantially All of the assets of the
                 Company; or
                 
          (v)    The liquidation or dissolution of the Company.

     (c)  Deferred Retirement and Deferred Retirement Date shall mean a
          participant's election to take deferred retirement pursuant to the
          provisions of the Retirement Plan for Salaried Employees of Pitt-Des
          Moines, Inc. and the Deferred Retirement Date as defined in such plan.
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     (d)  Early Retirement and Early Retirement Date shall mean a participant's
          election to take early retirement pursuant to the provisions of the
          Retirement Plan for Salaried Employees of Pitt-Des Moines, Inc. and
          the Early Retirement Date as defined in such plan.

     (e)  Fair Market Value of any Share shall mean the mean average of the high
          and low sales prices per Share as reported on the stock exchange or
          market on which such stock is traded or quoted on the trading day
          immediately preceding the relevant date under the Plan and if not so
          reported on said date, on the closest preceding day on which there
          were sales so reported.

     (f)  Non Qualified Stock Option shall mean any option to purchase a share
          of common stock of the Company granted pursuant to the Plan, which
          options do not qualify for treatment as incentive stock options under
          the Internal Revenue Code.

     (g)  Normal Retirement and Normal Retirement Date shall mean a
          participant's election to take normal retirement pursuant to the
          provisions of the Retirement Plan for Salaried such plan.

     (h)  Subsidiary or Subsidiaries shall mean any entity of which the Company,
          directly or indirectly, owns or controls 50% or more of the combined
          voting power.

     (i)  Substantially All shall mean more than 50% of the Fair Market Value of
          the total assets of the Company as of the end of its most recent
          fiscal quarter ending prior to the date such determination is made.