Cal. PCC § 20521

The city council shall make all contracts and all necessary provisions for the furnishing of the maintenance and operation finally determined upon for the lighting systems which are to be maintained and operated from funds of the district. Such contracts shall be made in the same manner and after the same notice and by the same persons as other city contracts for such items of maintenance and operation are made unless such contracts of the city are not required to be made after competitive bidding. In that case the contracts for the district shall be let only after competitive bidding and the officer whose duty it is to let contracts for such items for the city shall give or cause to be given a notice inviting sealed bids on the items to be purchased and fix a time and place at which the bids will be opened and declared in public. The contract shall be awarded to the lowest responsible bidder, or if necessary for the public good any and all bids may be rejected and in such case readvertisement shall be had in the same manner as before. The notice inviting bids shall be published at least twice and the first publication shall be at least 10 days before the time set for opening the sealed bids.