(1) Public bodies may enter into agreements with service providers for the furnishing of service in connection with water pollution control facilities pursuant to the process set forth in RCW 70A.140.040. The agreements may provide that a public body pay a minimum periodic fee in consideration of the service actually available without regard to the amount of service actually used during all or any part of the contractual period. Agreements may be for a term not to exceed forty years or the life of the facility, whichever is longer, and may be renewable.

(2) The source of funds to meet periodic payment obligations assumed by a public body pursuant to an agreement permitted under this section may be paid from taxes, or solely from user fees, charges, or other revenues pledged to the payment of the periodic obligations, or any of these sources.