40 U.S.C. chapter 31, subchapter IV, Wage Rate Requirements (Construction), formerly known as the Davis-Bacon Act, provides that contracts in excess of $2,000 to which the United States or the District of Columbia is a party for construction, alteration, or repair (including painting and decorating) of public buildings or public works within the United States, shall contain a clause (see 52.222-6) that no laborer or mechanic employed directly upon the site of the work shall receive less than the prevailing wage rates as determined by the Secretary of Labor.
48 C.F.R. §§22.403-1