California Code, Water Code - WAT § 60602

(a) An expenditure for the erection, construction, alteration, repair, or improvement of a public structure or building of twenty-five thousand dollars ($25,000) or more shall be let by contract by formal bidding procedure, consistent with the applicable provisions of the Public Contract Code.

(b) The district shall adopt policies and procedures, including formal and informal bidding requirements, governing contracts for professional services, materials, supplies, and equipment, provided that private architectural, landscape architectural, engineering, environmental, land surveying, or construction project management firms shall be selected pursuant to Chapter 10 (commencing with Section 4525) of Division 5 of Title 1 of the Government Code.

(c) This section shall remain in effect only until January 1, 2028, and as of that date is repealed.