Cal. Public Contract Code § 20221

(a) The purchase of all supplies, equipment, and materials when the expenditure required exceeds one hundred fifty thousand dollars ($150,000) shall be by contract let to the lowest responsible bidder or, in the district’s discretion, to the responsible bidder who submitted a proposal that provides the best value to the district on the basis of the factors identified in the solicitation. “Best value” means the overall combination of quality, price, and other elements of a proposal that, when considered together, provide the greatest overall benefit in response to requirements described in the solicitation documents. The construction of facilities and works when the expenditure required exceeds ten thousand dollars ($10,000) shall be by contract let to the lowest responsible bidder. Notice requesting bids shall be published at least once in a newspaper of general circulation. This publication shall be made at least 10 days before the bids are received. The board may reject any and all bids and readvertise in its discretion. (b) Whenever the expected procurement required exceeds five thousand dollars ($5,000) and, in the case of the construction of facilities and works, does not exceed ten thousand dollars ($10,000) or, in the case of the purchase of supplies, equipment, or materials, does not exceed one hundred fifty thousand dollars ($150,000), the district shall obtain a minimum of three quotations, either written or oral, that permit prices and terms to be compared. (c) Where the expenditure required by the bid price is less than one hundred thousand dollars ($100,000), the general manager may act for the board. When acting pursuant to this subdivision, the general manager shall, in each instance, promptly notify the board of the action taken.