If not the Edwards, then what?

Brian Smith, Brian Hunt, and W. F. (Kirk) Holland
Barton Springs/Edwards Aquifer Conservation District, Austin, Texas 78748

The Edwards Aquifer of Central Texas has been considered a vast source of inexpensive, high-quality drinking water for many years. However, restrictions have been placed on production from the Edwards in recent years. These restrictions are in recognition of the potential impacts of over-pumping on water-supply wells, water quality, springflow, and endangered species. Water suppliers have diversified their sources of water, but demand has increased faster than provision of other sources. With such longterm reliance on the Edwards Aquifer, other potential sources typically have been ignored. Potential sources within the boundaries of the Barton Springs/Edwards Aquifer Conservation District that are being minimally used, if at all, include the Middle and Lower Trinity aquifers, and the brackish portion of the Edwards. About a dozen Middle and Lower Trinity wells are used on a regular basis within the District. Yields from these wells are small compared to the Edwards, and water quality can be marginal or poor enough that treatment or blending is needed. The District has installed two multiport monitor wells to study the Edwards, Upper Trinity, and Middle Trinity aquifers. A multiport monitor well is now being planned to be installed in the brackish portion of the Edwards Aquifer. With a large quantity of brackish water in the eastern portion of the District, there is potential for desalination of this water with injection of the resulting concentrate in a deeper formation. Aquifer storage and recovery in the brackish Edwards is another option to be tested with these wells.

AAPG Search and Discovery Article #90158©2012 GCAGS and GC-SEPM 6nd Annual Convention, Austin, Texas, 21-24 October 2012