Cities of the second class and villages may cooperate with the United States Government in protecting against floods and enter into agreements with such government for that purpose. Such cities and villages may, in order to obtain federal funds for protecting against floods, consent to requirements of the Congress of the United States that such city or village (1) provide without cost to the United States all lands, easements, and rights-of-way necessary for the construction of flood control projects, (2) hold and save the United States free and harmless from damages due to the construction works, and (3) maintain and operate all the flood control works after completion in accordance with regulations prescribed by the Secretary of the Army of the United States.