A common supply of water may be acquired and developed (including acquisition or construction of all facilities necessary for distribution of water in bulk) by all of the contracting municipalities acting jointly or by the individual action of one of the contracting municipalities, acting for all of the contracting municipalities, as such municipalities may provide in the contract, or, pursuant to contract therewith, by a public authority which possesses express reciprocal powers of contract. Regardless of the method agreed upon, title to all real or personal property acquired or constructed shall be held jointly in the names of all of the contracting municipalities subject to such provisions for disposition as the contract between such municipalities may contain. Rider I. Such water authority shall be deemed the agent of the county or counties which are a party or parties to such contract. If such contract shall authorize the water authority to purchase supplies or equipment or to construct public works, such authority shall be subject to all provisions of law to which a county would be subject in relation to advertising and awarding any such contracts for supplies, equipment or public works.