(a) The principal of and interest on revenue bonds issued under this subchapter and the redemption price of the bonds must be secured by and payable solely from a pledge of all or any part of designated revenue resulting from the operations of the authority's water system.
(b) The board additionally may secure revenue bonds issued under this subchapter by a deed of trust or mortgage lien on all or part of the physical facilities of the authority as provided by Section 54.504, Water Code.
(c) The holders of revenue bonds issued under this subchapter may not demand payment from money raised or to be raised from taxation.