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Regulatory History of the Edwards Aquifer

Explains the history of State regulations to protect the Edwards Aquifer.

This page outlines only the key events in the history of the Edwards Aquifer Protection Program. For a comprehensive understanding of our TCEQ regulations protecting the Edwards Aquifer, we recommend you review the current rules. We also have several TCEQ publications to assist you and program staff are always available to answer your questions.

Legislative History

The Edwards Aquifer is one of the most valuable water resources in the central Texas area. This aquifer provides water for municipal, industrial, and agricultural uses. A number of cities rely on the aquifer as their only source of drinking water. In the past, the Aquifer has proved to be a reliable source of water through severe droughts. In fact, the Aquifer is the primary source of drinking water for over 1.7 million people in Central Texas. It covers 4,350 square miles in parts of 11 counties.

Over wide areas, the aquifer produces large volumes of water from several layers of highly permeable and porous honeycombed rock. Because the aquifer is highly permeable, and has rapid recharge and discharge, the aquifer produces large quantities of water. However, these same properties make the aquifer highly vulnerable to contamination where it is exposed at the surface in the aquifer recharge zone. Pollutants on and near the surface can directly enter the aquifer with little natural attenuation and travel long distances in a relatively short period of time.

In 1959, the Texas Legislature created the Edwards Underground Water District. The district supplied maps that were previously unavailable, and assisted licensing authorities. The importance of protecting the quality of the water in the Edwards Aquifer was not recognized until 1970, when the Texas Water Quality Board issued the first regulations for the protection of the aquifer recharge and buffer zones.

The first counties affected were Kinney, Uvalde, Medina, Bexar, Comal, and Hays. Sources of pollution such as underground storage tanks, above-ground storage tanks, and sewer lines were regulated.

Water-pollution abatement plans were first required in 1974. By 1984, the plans were required for regulated developments including residential, commercial, and industrial. A geologic assessment was required for housing developments with 100 or more family living units, and non-residential developments greater than 5 acres. Also in 1984, ongoing testing requirements for sewer lines were established.

Beginning in 1977, the installation of new underground storage tank sites had to be approved prior to construction. The sites were required to have double walled tanks and piping as well as a method of leak detection. These standards were in advance of the statewide regulations on underground storage tank systems that first went into effect in 1989.

In 1988, fees were assessed for all types of development. As a result of legislation, the schedule of fees was increased in 1997. These one-time fees cover the review of the protection plans as well as inspections during and after construction is complete. The money is used to support program efforts.

Upon petition by local government, construction activities in portions of Williamson County became regulated in 1986. Then in 1990, construction in portions of Travis County was first regulated.

Also in 1990, geologic assessment requirements for residential developments were decreased to 25 or more units, plus notification of recharge features was made mandatory. Today, a geologic assessment is required for all new, regulated developments except residential sites less than 10 acres.

Significant rules changes went into effect in 1999. The changes included a design performance standard for permanent best management practices. The standard applies to water quality systems used for stormwater treatment. Examples include sand filtration basins, extended detention basins, and retention ponds with irrigation systems. The rules also require engineers to certify the construction of the systems and to ensure maintenance of these systems.

The 1999 rules changes brought the contributing zone into regulation. Regulated activities are those that have the potential for polluting surface streams that will cross the recharge zone, including large construction projects and installation of petroleum storage tanks.

In 2001, the agency began distributing contributing-zone plans to affected municipalities, counties, or groundwater conservation districts according to House Bill 2912 (71st regular legislative session), which added Texas Water Code 26.137, mandating a 30-day public comment period for the applications. Also as a result of this House Bill, TWC §26.051 was added requiring the Texas Commission on Environmental Quality (TCEQ) to prepare reports of annual expenditures of funds related to the Edwards Aquifer Protection Program. Senate Bill 59 repealed TWC §26.051, effective September 1, 2013.

For More Information

You may also speak directly with TCEQ staff by calling our offices in Austin (Region 11) or San Antonio (Region 13).