(a) It is declared that water and wastewater treatment authorities created pursuant to this part shall be public and governmental bodies acting as agencies and instrumentalities of the creating and participating governmental entities; and that the acquisition, operation and finance of water and wastewater treatment works by such authorities is declared to be for a public and governmental purpose and a matter of public necessity.
(b) The property and revenues of the authority, or any interest therein, are exempt from all state, county and municipal taxation.