Several units of local government in Texas were authorized to engage in water programs. Counties, cities, and other kinds of water districts were authorized by statute to undertake certain projects. The extent to which the units actually exercised their authority, however, varied considerably. Early in the state's development, counties were relied upon to undertake certain water functions. They were authorized to clear and improve streams for navigation and to make drainage and flood-control improvements on petition of property owners. These programs were limited, however, because constitutional provisions permitted only a special assessment tax to finance such improvements. The county remained the only unit of local government authorized to perform these services until 1904, when the constitution was amended to permit the establishment of special districts. After that time these new units assumed most of the duties of making the improvements. Counties, however, continued to participate in water programs as administrative areas of the state government. They were responsible for enforcing state laws, including fish and game laws and water laws pertaining to water districts. Under water law statutes, the commissioners' court of a county was empowered to create numerous kinds of water districts. The county board appointed the governing boards of drainage, navigation, and levee districts, and the boards of water control and preservation districts situated in only one county. Counties also had a certain amount of supervisory authority over general-law water districts. The county auditor had general supervision over the books and records of all the county officers, including those of the water districts.
After the constitutional amendment of 1904, which authorized the first public development of water resources, water districts became the most important unit of local government to undertake water programs. Water districts in Texas direct all the major water programs, including flood control, drainage, navigation, irrigation, domestic, commercial, and industrial water supply, sewage disposal, power supply, groundwater control, mosquito control, soil conservation, and recreation. These tasks of supplying or controlling water often involve the construction of levees, dams, lakes, and power facilities, or the channeling, clearing, and maintenance of streams and rivers. In 1949 the Texas Legislature authorized the creation of underground water districts with local voter approval. By 1966 there were more than 793 water districts in the state, counting all districts created under both general and special laws. The types of general-law water districts were water control and improvement, water improvement, fresh water supply, underground water conservation, irrigation, levee improvement, drainage, and navigation districts, as well as conservation and reclamation, water control and preservation, water power control, water supply, and municipal water districts. There was little control over water districts by either state agencies or the public, and this caused a great deal of criticism. The rapid multiplication of disparate, often overlapping water districts made it impossible for even the most conscientious citizen to understand their problems and activities. As a result, in 1961 the state legislature enacted a provision which provided that no districts except water control and improvement districts and underground water conservation districts could thereafter be established. The legislature also empowered the Texas Water Commission to supervise and coordinate activities of water districts. The prohibition on creating other types of districts, however, was declared unconstitutional in the case of Harris County Fresh Water Supply District, No. 55 v. Carr in 1963.
Cities had a vital concern in maintaining adequate municipal water supply. Texas cities could establish municipal water systems and issue the bonds required to construct them if such construction and bonding were approved in popular elections. Cities were also authorized to construct sewer systems and sewage disposal plants, most of which had to be financed by means of voter-approved bond issues. Flood-protection measures were also undertaken by cities, since many cities were located on or near streams subject to overflow. Home rule cities that had the power to improve any river or stream within the city and to levy a special assessment on the property owners especially benefited. They could also establish improvement districts to undertake such projects. Texas cities located on navigable streams could acquire land for the purpose of establishing and maintaining wharves, docks, railway terminals, and other aids to navigation. They could also deed this property to the federal government for the improvement of navigation. Any city situated within the territorial limits of a navigation district and having a deepwater port could purchase, construct, own, and maintain dikes, spillways, seawalls, and breakwaters to protect the city. Furthermore, the city could elevate and reclaim submerged or low lands along the waterfront, dredge channels, and build and operate dry docks, piers, wharves, and boat basins. To finance these improvements for their harbors, coastal cities could issue bonds. Texas cities could also generate, purchase, and distribute hydroelectric power, own and operate municipal electric plants, and contract with other generating agencies for electrical energy. In 1987 more than 5,000 local agencies and corporations were involved in supplying water for municipal, industrial, and agricultural use. Local water suppliers mainly included municipal utility districts, cities, water supply corporations, and private water suppliers. There were more than 1,000 municipal utility districts that, through voter approved bond elections, could develop water resources by building reservoirs, drilling wells, or constructing treatment plants among other options. Twelve underground water districts in existence in 1987 worked to improve conservation and recharge and conducted educational campaigns on waste prevention.