Texas Health and Safety Code - HEALTH & SAFETY § 366.036. County Map

(a) If the commission designates a local governmental entity as its authorized agent and if the entity intends to apply to the Texas Water Development Board for financial assistance under a program for economically distressed areas, the commissioners court of the county in which the entity is located shall prepare a map of the county area outside the limits of municipalities. The entity shall give to the commissioners court a written notice of the entity's intention to apply for the assistance. The map must show the parts of the area in which the different types of on-site sewage disposal systems may be appropriately located and the parts in which the different types of systems may not be appropriately located.

(b) The commissioners court shall file the map in the office of the county clerk.

(c) The commissioners court, at least every five years, shall review the map and make changes to it as necessary to keep the map accurate.