(a) The board may provide for an extension or improvement to a utility system.
(b) The board may not provide for the extension of service to an area within the boundaries or extraterritorial jurisdiction of a municipality or within a conservation and reclamation district created under Section 59, Article XVI, Texas Constitution, without the consent of the governing body of the municipality or district.
(c) The service area of the board may not include territory that on June 6, 1993, was served by another utility under a certificate of public convenience and necessity unless the certificate ceases to be effective.