South-Central Section–40th Annual Meeting (6–7 March 2006)

Paper No. 12
Presentation Time: 8:20 AM-12:00 PM

HYDROGEOLOGIC MAPS OF UVALDE COUNTY, TEXAS


MOEDE, Ian H., Department of Geological Sciences, The University of Texas, 1 University Station-C1100, Austin, TX 78712-0254, ianmoede@mail.utexas.edu

This set of maps depicts geological and anthropogenic features that are important to understanding the hydrogeology of Uvalde County, Texas. Included are maps of geology, aquifer outcrop, precipitation, topography, temporal head changes, spring locations, and man-made features. Uvalde County has no surface water storage or conveyances of potable water into the county. Consequently, groundwater availability and quality are very important to long term sustainability. Maps were created from pre-existing databases or georeferenced using GIS software. Maps of water-table levels were derived from these databases and divided into 10-year groups to ascertain whether head has changed temporally. The maps show that head levels fluctuate over time but do not display long-term trends. Groundwater flow directions have changed due to pumping, but do not appear to have affected the water in storage or the quality of water in the county. Water demand for Uvalde County is projected to decrease due to a decline in irrigation and a relatively slowly growing population.