In this chapter:
(1) "District" means a municipal utility district operating under this chapter.
(2) "Board" means the board of directors of a district.
(3) "Director" means a member of the board of directors of a district.
(4) "Commission" means the Texas Commission on Environmental Quality.
(5) "Executive director" means the executive director of the Texas Commission on Environmental Quality.
(6) "Public agency" means any city, the United States, the State of Texas, and any district or authority created under Article XVI, Section 59, or Article III, Section 52, of the Texas Constitution, including any river authority, or any other political subdivision or governmental agency of the United States or the State of Texas.
(7) "City" means any incorporated city, town, or village of the State of Texas whether operating under general law or under its home-rule charter.
(8) "Extraterritorial jurisdiction" means the extraterritorial jurisdiction of a city as defined in Article I, Chapter 160, Acts of the 58th Legislature, 1963, as amended (Article 970a, Vernon's Texas Civil Statutes).
(9) "Sole expense" means the actual cost of the relocation, raising, rerouting, or changing grade or alteration of construction and providing comparable replacement without enhancing the facilities after deducting from it the net salvage value derived from the old facility.