<PAGE>

                                                                  Exhibit 10.1.a

                              GRANITE CONSTRUCTION

                          EMPLOYEE STOCK OWNERSHIP PLAN

                  Amendment No. 1 to Amended and Restated Plan

        WHEREAS, Granite Construction Incorporated (the "Company") maintains the
Granite Construction Employee Stock Ownership Plan (the "Plan") for the benefit
of eligible Employees; and


        WHEREAS, it is desirable to clarify certain Plan provisions to reflect
the requirements of the Internal Revenue Code of 1986, as amended by the Small
Business Job Protection Act of 1996, the Taxpayer Relief Act of 1997, the
Internal Revenue Service Restructuring and Reform Act of 1998, and the Economic
Growth and Tax Relief Reconciliation Act of 2001.

        NOW, THEREFORE, the Plan is hereby amended as follows:

        1. Section 2 is amended by restating the definition of "Compensation" to
read as follows, effective as of January 1, 2002:

<TABLE>
  <S>                                          <C>

  Compensation .............................    The Statutory Compensation paid to an
                                                Employee by his Employer, but excluding
                                                (1) reimbursements or other expense
                                                allowances (including travel expense
                                                allowances), (2) fringe benefits (cash and
                                                noncash), (3) moving expenses, (4) welfare
                                                benefits, (5) any amount in excess of
                                                $200,000 (as adjusted periodically after
                                                2002 for increases in the cost of living
                                                pursuant to Section 401(a)(17) of the
                                                Code) and (6) any amount paid to an
                                                Employee

</TABLE>
<PAGE>


pursuant to the terms of a collective bargaining agreement.

        2. Section 2 is further amended by restating the definition of
"Employee" to read as follows, effective as of January 1, 1997:


<TABLE>
  <S>                                          <C>

  Employee .................................    Any individual who is treated by an
                                                Employer as a common-law employee;
                                                provided, however, that an independent
                                                contractor (or other individual) who is
                                                reclassified as a common-law employee on a
                                                retroactive basis shall not be treated as
                                                having been an Employee for purposes of
                                                the Plan for any period prior to the date
                                                that he is so reclassified. A leased
                                                employee is not an Employee for purposes
                                                of the Plan. For this purpose, a "leased
                                                employee," as described in Section 414(n)
                                                of the Code, is any individual who is not
                                                treated as a common-law employee by the
                                                Company or an Affiliate and who provides
                                                services to the Company or an Affiliate if
                                                (A) such services are provided pursuant to
                                                an agreement between the Company or an
                                                Affiliate and a leasing organization, (B)
                                                such individual has performed services for
                                                the Company or an Affiliate on a
                                                substantially full-time basis for a period
                                                of at least one year, and (C) such
                                                services are performed under the primary
                                                direction or control of the Company or an
                                                Affiliate.
</TABLE>


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<PAGE>

        3. Section 7 is amended by restating the first paragraph thereof to read
as follows, effective as of January 1, 2002:

           The Annual Additions for each Plan Year with respect to any
        Participant may not exceed the lesser of:

                (1) 100% of his Statutory Compensation; or

                (2) $40,000, as may be adjusted for increases in the cost of
                    living pursuant to Section 415(d)(l)(C) of the Code.

        For this purpose, "Annual Additions" shall be the total of the Employer
        Contributions and Forfeitures (including any income attributable to
        Forfeitures) allocated to the Accounts of a Participant for the Plan
        Year, excluding any Employer Contributions which are used by the Trust
        (not later than the due date, including extensions, for filing the
        Company's Federal income tax return for that Plan Year) to pay interest
        on a Loan and any Financed Shares which are allocated as Forfeitures,
        plus any employer contributions (including 401(k) contributions) and
        forfeitures allocated to him under the Profit Sharing Plan for the Plan
        Year. In determining such Annual Additions, Forfeitures of Stock shall
        be included at the Fair Market Value as of the Allocation Date and
        Employer Contributions in the form of Stock shall be included at the
        Fair Market Value as of the date such shares are issued to the Trust.


                                      -3-
<PAGE>

        4. Section 9(b) is restated to read as follows, effective as of January
1, 1999:

           (b) Summary Annual Report - Within two months after the due date for
        filing the annual return/report (Form 5500) for the Plan with the U.S.
        Department of Labor, each Participant shall be furnished with the
        summary annual report of the Plan required by Section 104(b)(3) of
        ERISA, in the form prescribed in regulations of the U.S. Department of
        Labor.

        5. Section 9(d) is amended by restating the first sentence thereof to
read as follows, effective as of January 1, 1999:

        The Company shall make available for examination by any Participant
        copies of the Plan, the Trust Agreement and the latest annual
        return/report of the Plan filed (on Form 5500) with the U.S. Department
        of Labor.

        6. Section 11(b) is amended by deleting the third paragraph thereof in
its entirety, effective as of January 1, 1998.


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<PAGE>

        7. Section 12(a) is amended by restating the second sentence thereof to
read as follows, effective as of January 1, 1998:

        If the value of a Participant's Capital Accumulation exceeds $5,000, no
        portion of his Capital Accumulation may be distributed to him before he
        attains age 65 without his written consent.

        8. Section 12(e) is amended by restating the third sentence thereof to
read as follows, effective as of January 1, 1998:

        If the value of a Participant's Capital Accumulation exceeds $5,000, no
        portion of such Capital Accumulation may be distributed to his former
        spouse or other alternate payee, without the written consent of such
        former spouse or other alternate payee.

        9. Section 14(e) is restated to read as follows, effective as of January
1, 1999:

               (e) If a distribution of a Participant's Capital Accumulation is
        neither the minimum amount required to be distributed pursuant to the
        second and third sentences of Section 12(c) nor a hardship distribution
        (including withdrawals described in Section 13(c) and, prior to January
        1, 2002, a hardship distribution of "elective deferrals" as described in
        Section 401(k)(2)(IV) of the Code only), the Committee shall notify the
        Participant (or any spouse or former spouse who is his alternate payee
        under a "qualified domestic relations order" (as defined in Section
        414(p) of the Code)) of his right to elect to have the "eligible
        rollover distribution" paid directly to an "eligible retirement plan"


                                      -5-
<PAGE>

        (within the meaning of Section 401 (a)(31) of the Code) that is an
        individual retirement account described in Section 408(a) of the Code,
        an individual retirement annuity described in Section 408(b) of the
        Code, a qualified trust described in Section 401(a) of the Code or a
        qualified annuity plan described in Section 403(a) of the Code (and for
        transfers or distributions after December 31, 2001, an annuity contract
        described in Section 403(b) or an eligible plan described in 457(b) of
        the Code which is maintained by a state, political subdivision of a
        state, or any agency or instrumentality of a state or political
        subdivision of a state) that accepts "eligible rollover distributions."
        For distributions made prior to January 1, 2002, if such an "eligible
        rollover distribution" is to be made to the Participant's surviving
        spouse, the Committee shall notify the surviving spouse of his right to
        elect to have the distribution paid directly only to an "eligible
        retirement plan" that is either an individual retirement account
        described in Section 408(a) of the Code or an individual retirement
        annuity described in Section 408(b) of the Code. Any election under this
        Section 14(e) shall be made and effected in accordance with such rules
        and procedures as may be established from time to time by the Committee
        in order to comply with Section 401(a)(31) of the Code.

        10. Section 15 is restated to read as follows, effective for judgments,
orders, and decrees issued, and settlement agreements entered into, on or after
August 5, 1997:

               A Participant's Capital Accumulation may not be anticipated,
        assigned (either at law or in equity), alienated or subject to
        attachment, garnishment, levy, execution or other legal or equitable
        process, except in accordance with (i) a "qualified domestic relations
        order" (as defined in Section 414(p) of the Code); (ii) a federal tax
        levy or


                                      -6-
<PAGE>

        collection by the Internal Revenue Service on a judgment resulting from
        an unpaid tax assessment; or (iii) a judgment or settlement described in
        Section 401(a)(13)(C) of the Code.

        To record the adoption of this Amendment No. 1 to the Plan, the Company
has caused it to be executed this 11th day of February, 2002.



                                   GRANITE CONSTRUCTION
                                   INCORPORATED

                                   By  /s/ WILLIAM G. DOREY
                                     -----------------------------------
                                       William G. Dorey
                                   Its Executive Vice President,
                                       Chief Operating Officer



                                   By  /s/  MICHAEL FUTCH
                                     -----------------------------------
                                       Michael Futch
                                   Its Vice President,
                                       Secretary

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