Lab. Code, § 1773.9

(a) The Director of Industrial Relations shall use the methodology set forth in subdivision (b) to determine the general prevailing rate of per diem wages in the locality in which the public work is to be performed.

(b) The general prevailing rate of per diem wages includes all of the following:

(1) The basic hourly wage rate being paid to a majority of workers engaged in the particular craft, classification, or type of work within the locality and in the nearest labor market area, if a majority of the workers is paid at a single rate. If no single rate is being paid to a majority of the workers, then the single rate being paid to the greatest number of workers, or modal rate, is prevailing. If a modal rate cannot be determined, then the director shall establish an alternative rate, consistent with the methodology for determining the modal rate, by considering the appropriate collective bargaining agreements, federal rates, rates in the nearest labor market area, or other data such as wage survey data.

(2) Other employer payments included in per diem wages pursuant to Section 1773.1 and as included as part of the total hourly wage rate from which the basic hourly wage rate was derived. In the event the total hourly wage rate does not include any employer payments, the director shall establish a prevailing employer payment rate by the same procedure set forth in paragraph (1).

(3) The rate for holiday and overtime work shall be those rates specified in the collective bargaining agreement when the basic hourly rate is based on a collective bargaining agreement rate. In the event the basic hourly rate is not based on a collective bargaining agreement, the rate for holidays and overtime work, if any, included with the prevailing basic hourly rate of pay shall be prevailing.

(c) (1) If the director determines that the general prevailing rate of per diem wages is the rate established by a collective bargaining agreement, and that the collective bargaining agreement contains definite and predetermined changes during its term that will affect the rate adopted, the director shall incorporate those changes into the determination. Predetermined changes that are rescinded prior to their effective date shall not be enforced.

(2) When the director determines that there is a definite and predetermined change in the general prevailing rate of per diem wages as described in paragraph (1), but has not published, at the time of the effective date of the predetermined change, the allocation of the predetermined change as between the basic hourly wage and other employer payments included in per diem wages pursuant to Section 1773.1, a contractor or subcontractor may allocate payments of not less than the amount of the definite and predetermined change to either the basic hourly wage or other employer payments included in per diem wages for up to 60 days following the director’s publication of the specific allocation of the predetermined change.

(3) When the director determines that there is a definite and predetermined change in the general prevailing rate of per diem wages as described in paragraph (1), but the allocation of that predetermined change as between the basic hourly wage and other employer payments included in per diem wages pursuant to Section 1773.1 is subsequently altered by the parties to a collective bargaining agreement described in paragraph (1), a contractor or subcontractor may allocate payments of not less than the amount of the definite and predetermined change in accordance with either the originally published allocation or the allocation as altered in the collective bargaining agreement.