Any public agency entering into an agreement pursuant to this act may appropriate funds and may sell, lease, give, or otherwise supply to the district created such personnel or services for the operation of such district as may be within its legal power to furnish. Any public agency, whether or not a party to an agreement pursuant to Kan. Stat. Ann. § 19-3547, and any publicly or privately owned water distribution company may enter into contracts with any district created pursuant to the public wholesale water supply district act for the purchase of water from such district or the sale of water to the district, the treatment of water by either party and/or the distribution or transmission of water by either party and any such district may enter into such contracts. Any such contract may include an agreement for the purchase of water not actually received. No such contract shall be made for a period in excess of forty (40) years, but renewal options in favor of the purchasing entity may be included therein. The obligations of any public agency under any such contract shall be payable solely from the revenues produced from such public agency’s water system and shall not be payable from any funds raised by taxation.