(a) If any area in which water rights of record in the office of the commission have not been adjudicated, the claimants of the rights and the commission may enter into a written agreement for their administration.
(b) An agreement made under authority of this section shall provide:
(1) the basis and manner of distribution of the water to which the agreement relates;
(2) the services of a special watermaster, and assistants if necessary, to carry out the agreement; and
(3) the allocation, collection, and payment of the annual costs of administration.
(c) An agreement to administer unadjudicated water rights shall be recorded in the offices of the commission and of the county clerk of each county in which any of the works or lands affected by the agreement are located.
(d) The administration of water rights by agreement is governed by the provisions of this subchapter except as regards allocation and payment of the expenses of the administration.
(e) No agreement authorized by this section impairs any vested right to the use of water or creates any additional rights to the use of water.