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Exhibit 10.5

FOURTH AMENDMENT TO CREDIT AGREEMENT

        THIS AMENDMENT TO CREDIT AGREEMENT (this "Amendment") is entered into as
of March 30, 2009, by and between WILLDAN GROUP, INC., a Delaware corporation
("Borrower"), and WELLS FARGO BANK, NATIONAL ASSOCIATION ("Bank").

RECITALS

        A.    Borrower is currently indebted to Bank pursuant to the terms and
conditions of that certain Credit Agreement between Borrower and Bank dated as
of December 28, 2007, as amended from time to time ("Credit Agreement").

        B.    Pursuant to Section 4.9 (b) of the Credit Agreement, Borrower and
its Subsidiaries were required to maintain, on a consolidated basis, net losses
before taxes of not more than $1,000,000.00 on an annual basis as of the fiscal
year ending January 2, 2009. Borrower and its Subsidiaries sustained net losses
before taxes of more than $1,000,000.00 in the fiscal year ending January 2,
2009, resulting in a violation of this covenant and an Event of Default under
the Credit Agreement (the "Existing Default").

        C.    Borrower has requested that Bank waive the Existing Default and
Bank has agreed to do so, subject to the terms and conditions set forth herein.
In addition, Bank and Borrower have agreed to certain changes in the terms and
conditions set forth in the Credit Agreement and have agreed to amend the Credit
Agreement to reflect said changes.

        NOW, THEREFORE, for valuable consideration, the receipt and sufficiency
of which are hereby acknowledged, the parties hereto agree that the Credit
Agreement shall be amended as follows:

        1.     The Line of Credit Note dated December 28, 2007 referred to
Section 1.1 (a) of the Credit Agreement shall be replaced with a promissory note
dated as of March 30, 2009, (which promissory note shall be deemed the Line of
Credit Note defined in and made pursuant to the Credit Agreement).

        2.     Section 1.2 (c) is hereby deleted in its entirety, and the
following substituted therefor:

        "(c)    Unused Commitment Fee.    Borrower shall pay to Bank a fee equal
to thirty-five hundredths percent (0.35%) per annum (computed on the basis of a
360-day year, actual days elapsed) on the average daily unused amount of the
Line of Credit, which fee shall be calculated on a fiscal quarterly basis by
Bank and shall be due and payable by Borrower in arrears within ten (10) days
after each billing is sent by Bank."

        3.     Section 1.4 is hereby deleted in its entirety, and the following
substituted therefor:

        "SECTION 1.4.    COLLATERAL.

        As security for all indebtedness and other obligations of Borrower to
Bank subject hereto, Borrower hereby grants to Bank security interests of first
priority in all Borrower's accounts receivable and other rights to payment,
general intangibles, inventory, equipment and custody account number 13041132
held with Wells Fargo Institutional Securities, LLC.

        As security for all indebtedness and other obligations of Borrower to
Bank subject hereto, Borrower shall cause Willdan Financial Services, Willdan
Geotechnical; Willdan Engineering, Willdan Homeland Solutions, Willdan Energy
Solutions and any other Subsidiary (as defined below) to grant to Bank security
interests of first priority in all

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accounts receivable and other rights to payment, general intangibles, inventory
and equipment.

        All of the foregoing shall be evidenced by and subject to the terms of
such security agreements, financing statements, deeds or mortgages, and other
documents as Bank shall reasonably require, all in form and substance
satisfactory to Bank. Borrower shall pay to Bank immediately upon demand the
full amount of all charges, costs and expenses (to include fees paid to third
parties and all allocated costs of Bank personnel), expended or incurred by Bank
in connection with any of the foregoing security, including without limitation,
filing and recording fees and costs of appraisals, audits and title insurance."

        4.     Section 4.3 (c) is hereby deleted in its entirety, and the
following substituted therefor:

        "(c) not later then 30 days after and as of the end of each month,
brokerage statements of Borrower;"

        5.     Section 4.9 is hereby deleted in its entirety, and the following
substituted therefor:

        "SECTION 4.9.    TANGIBLE NET WORTH.    Using generally accepted
accounting principles consistently applied and used consistently with prior
practices (except to the extent modified by the definitions herein), Borrower
shall, and shall cause each Subsidiary to, maintain the Tangible Net Worth of
Borrower and its Subsidiaries, on a consolidated basis, of not less than
$18,000,000.00 at any time. As used herein, "Tangible Net Worth" is defined as
the aggregate of total stockholders' equity less any intangible assets and less
any loans or advances to, or investments in, any related entities or
individuals."

        6.     Subject to the terms and conditions set forth herein, Bank hereby
waives the Existing Default. This waiver applies only to the Existing Default.
It is not a waiver of any breach of any other provision of the Credit Agreement.
Except as expressly stated in this Amendment, Bank reserves all of the rights,
powers and remedies available to Bank under the Credit Agreement and any other
contracts or instruments signed by Borrower or any guarantor, including the
right to cease making advances to Borrower and the right to accelerate any of
Borrower's indebtedness, if any subsequent breach of any other provision of the
Credit Agreement should occur.

        7.     Except as specifically provided herein, all terms and conditions
of the Credit Agreement remain in full force and effect, without waiver or
modification. All terms defined in the Credit Agreement shall have the same
meaning when used in this Amendment. This Amendment and the Credit Agreement
shall be read together, as one document.

        8.     Borrower hereby remakes all representations and warranties
contained in the Credit Agreement and reaffirms all covenants set forth therein.
Borrower further certifies that as of the date of this Amendment there exists no
Event of Default as defined in the Credit Agreement, nor any condition, act or
event which with the giving of notice or the passage of time or both would
constitute any such Event of Default.

        IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be
executed as of the day and year first written above.

WILLDAN GROUP, INC.   WELLS FARGO BANK,
NATIONAL ASSOCIATION
By:
 
/s/ Kimberly Gant

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Kimberly Gant
 
By:
 
/s/ Randall Repp

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Randall Repp Title:   Chief Financial Officer       Vice President

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Exhibit 10.5

FOURTH AMENDMENT TO CREDIT AGREEMENT