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                                                                    EXHIBIT 10.2

                       CONSENT AND AGREEMENT OF GUARANTORS

            Reference is made to that Credit Agreement dated as of June 27, 2003
among Granite Construction Incorporated, Bank of America, N.A., as
Administrative Agent, and the Lenders party thereto (as amended, the "Credit
Agreement"). Each of the undersigned, in its capacity as a Guarantor
(hereinafter defined), acknowledges that its consent to the foregoing First
Amendment Agreement to the Credit Agreement dated as of September 15, 2004 (the
"Amendment") is not required, but each Guarantor nevertheless does hereby
consent to the foregoing Amendment and to the documents and agreements referred
to therein. Nothing herein shall in any way limit any of the terms or provisions
of that Continuing Guaranty Agreement dated as of June 27, 2003, (the
"Guaranty") made by Granite Construction Company, a California corporation,
Granite Land Company, a California corporation, Intermountain Slurry Seal, Inc.,
a Wyoming corporation, Pozzolan Products Company, a Utah corporation, GILC, L.P.
a California limited partnership, Granite Halmar Construction Company, Inc., a
New York corporation (each a "Guarantor" and collectively, the "Guarantors"), in
favor of each Guaranteed Party or any other Loan Document executed by a
Guarantor (as the same may be amended from time to time), all of which are
hereby ratified and affirmed in all respects.

                  Each Guarantor further agrees that its respective Guaranty
shall be amended as follows:

            (a) Section 3.1 is amended by deleting such section in its entirety
and replacing it with the following:

                  "Section 3.1 Nature and Application of Payments. Each
            Guarantor shall make all payments hereunder in immediately available
            lawful money in the Obligation Currency (as hereinafter defined) or,
            if required by the Administrative Agent, in lawful money of the
            United States, in each case, in immediately available funds without
            deduction or withholding (whether for taxes (whether income, excise,
            or otherwise) or offset). Without regard to the form in which
            received, the Guaranteed Parties may apply any payment with respect
            to the Guaranteed Obligations or any other amounts due hereunder in
            such order as the Guaranteed Parties shall in their sole and
            absolute discretion determine, irrespective of any contrary
            instructions received from any other Person."

            (b) Article IX is amended by adding the following Section 9.4 and
Section 9.5 immediately after Section 9.3 thereof:

                  "Section 9.4 Foreign Currency. If any claim arising under or
            related to this Guaranty is reduced to judgment denominated in a
            currency (the "Judgment Currency") other than the currencies in
            which the Guaranteed Obligations are denominated (collectively, the
            "Obligation Currency"), the judgment shall be for the equivalent in
            the Judgment Currency of the amount of the claim denominated in the
            Obligations Currency included in the judgment, determined as of the
            date of judgment. The equivalent of any Obligations Currency amount
            in any Judgment Currency shall be calculated at the spot rate for
            the purchase of the Obligations Currency with the Judgment Currency
            quoted by the Administrative Agent in the

                                       1
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            place of the Administrative Agent's choice at or about 8:00 a.m.
            (San Francisco time) on the date for determination specified above.
            The Guarantor shall indemnify and hold the Guaranteed Parties
            harmless from and against all loss or damage resulting from any
            change in exchange rates between the date any claim is reduced to
            judgment and the date of payment thereof by the Guarantor. If the
            Guaranteed Parties so notify the Guarantor in writing, at the
            Administrative Agent's sole and absolute discretion, payments under
            this Guaranty shall be the U.S. Dollar equivalent of the Guaranteed
            Obligations or any portion thereof, determined as of the date
            payment is made."

                  "Section 9.5 USA PATRIOT Act Notice. Each Lender that is
            subject to the Act (as hereinafter defined) and the Administrative
            Agent (for itself and not on behalf of any Lender) hereby notifies
            each Guarantor that pursuant to the requirements of the USA Patriot
            Act (Title III of Pub. L. 107-56 (signed into law on October 26,
            2001)) (the "Act"), it is required to obtain, verify and record
            information that identifies each Guarantor, which information
            includes the name and address of each Guarantor and other
            information that will allow such Lender or the Administrative Agent,
            as applicable, to identify each Guarantor in accordance with the
            Act."

            Each capitalized term used but not otherwise defined in the Guaranty
or herein, shall have the meanings assigned to them in the Credit Agreement (as
amended by the Amendment).

      [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK. SIGNATURE PAGES FOLLOW]

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            This Consent and Agreement of Guarantors shall constitute a Loan
Document under the Credit Agreement and may be executed in any number of
counterparts, each of which shall be deemed an original, but all such
counterparts together shall constitute but one instrument.

                                       GRANITE CONSTRUCTION COMPANY,
                                       a California corporation

                                       By: /s/ William G. Dorey
                                          -------------------------------------
                                           William G. Dorey
                                           President & Chief Executive Officer

                                       By: /s/ William E. Barton
                                          -------------------------------------
                                           William E. Barton
                                           Chief Financial Officer

                                       GRANITE LAND COMPANY,
                                       a California corporation

                                       By: /s/ Mark E. Boitano
                                          -------------------------------------
                                           Mark E. Boitano
                                           Executive Vice President, Granite
                                           Construction Incorporated

                                       By: /s/ William E. Barton
                                          -------------------------------------
                                           William E. Barton
                                           Chief Financial Officer, Granite
                                           Construction Incorporated

                                       INTERMOUNTAIN SLURRY SEAL, INC.,
                                       a Wyoming corporation

                                       By: /s/ Michael L. Thomas
                                          -------------------------------------
                                           Michael L. Thomas
                                           President

                                       By: /s/ David J. Brunton
                                          -------------------------------------
                                           David J. Brunton
                                           Chief Financial Officer

            [SIGNATURE PAGE 1 TO CONSENT AND AGREEMENT OF GUARANTORS]

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                                       POZZOLAN PRODUCTS COMPANY (P.P.C.),
                                       a Utah corporation

                                       By: /s/ Michael L. Thomas
                                          -------------------------------------
                                           Michael L. Thomas
                                           President

                                       By: /s/ David J. Brunton
                                          -------------------------------------
                                           David J. Brunton
                                           Chief Financial Officer

                                       GILC, L.P.,
                                       a California Limited Partnership

                                       By: GILC Incorporated
                                       its General Partner

                                       By: /s/ William E. Barton
                                          -------------------------------------
                                           William E. Barton
                                           President & Chief Executive Officer

                                       By: /s/ Roxane C. Allbritton
                                          -------------------------------------
                                           Roxane C. Allbritton
                                           Chief Financial Officer

                                       GRANITE HALMAR CONSTRUCTION COMPANY,
                                       INC., a New York corporation

                                       By: /s/ William G. Dorey
                                          -------------------------------------
                                           William G. Dorey
                                           President & Chief Executive Officer

                                       By: /s/ William E. Barton
                                          -------------------------------------
                                           William E. Barton
                                           Chief Financial Officer

            [SIGNATURE PAGE 2 TO CONSENT AND AGREEMENT OF GUARANTORS]

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DATED September 15, 2004
Accepted:

BANK OF AMERICA, N.A., as Administrative Agent

By:  /s/ Suzie Anna Wan
   -----------------------------------
     Suzie Anna Wan
     AVP

            [SIGNATURE PAGE 3 TO CONSENT AND AGREEMENT OF GUARANTORS]