JACK SHARP AND THE AQUIFERS OF CENTRAL TEXAS

Since John M. (Jack) Sharp Jr. arrived at The University of Texas at Austin 35 years ago to teach hydrogeology, he has taught and supervised thousands of students. Some of these students stayed in central Texas to work as professional hydrogeologists, and they continue to seek out his advice on hydrogeology. As busy as Jack is with his teaching and supervising duties, world travel, and family commitments, he has always been willing to listen and offer advice to ex-students that track him down in his office.

Jack has guided numerous models of the Edwards Aquifer and insists that verification testing of the models be done after a few years of post-model data are collected. He has guided studies that incorporate complex models into decision support systems that even regulators and politicians can use. These models now inform us of how to determine the sustainable, or consensus, yield of an aquifer. He has shown us how the karst of the Edwards Aquifer is overlain by an urban karst system of leaky pipes and gravel backfill. Jack and his students have discovered that asphalt and concrete surfaces are not impermeable, but can be direct contributors of contaminants into our aquifers. After conducting several studies of the saline portion of the Edwards Aquifer, Jack concluded that the “bad-water” zone is not so bad, especially when the demand for water in central Texas is high and there are technologies for making the water good.

Jack continues to act as a mentor and advisor to previous students, and to many others that never set foot in his classroom. His contribution to the knowledge of the aquifers in central Texas is significant and long lasting. We hope that even in retirement, Jack will send out the monthly hydro newsletters and will round up UT alumni at conferences for those group shots that will undoubtedly end up in next month’s newsletter.