ICOSA
Aquifer Development Horse Has Left Barn
RECEIVED Tue., Jan. 3, 2006
Dear Editor,
Recent Chronicle issues (“Back to the Trenches,” News, Dec. 16; “Saying ‘No’ to AMD,” News, Dec. 23, and “AMD Sets Its Site on Lantana,” News, Dec. 23; and “Blame It on Grandpa,” News, Dec. 30) seem to predict the imminent demise of the Edwards Aquifer should AMD proceed. Examination of satellite imagery and geologic maps shows that most of the land in the local Edwards Aquifer direct recharge zone has already been extensively developed. This includes the south MoPac corridor, Barton Hills neighborhood, Barton Creek Mall, Travis Country subdivisions, the huge malls in Sunset Valley, and the sprawling residential subdivisions south of 290. All of these lie directly atop the Edwards Aquifer, which regionally flows northward to Barton Springs. The Edwards Aquifer contributing zone is similarly developed, particularly along highways 290 and 71. Assuming these existing high-density developments have not already ruined the aquifer and Barton Springs, I doubt that development of the AMD tract (especially as proposed) and the few remaining parcels in the vicinity will have significant additional impact. Dye-tracer studies have shown that surface runoff from Lantana will likely re-emerge at Cold Springs on Town Lake, thereby bypassing Barton Springs entirely. Hence, notional arguments of ruinous follow-on secondary development and pollution appear to be specious. Further, Freescale Semiconductor’s large (1.5 million-square-foot) headquarters with 2,700 employees directly adjacent to the Lantana tract would seem to set a precedent for such development. In short, the proverbial horse has already long left the barn in terms of discouraging development directly on the aquifer and in the contributing zone. It seems that an opportunity has presented itself to use the AMD approach to create a model, an expected standard, perhaps even a mandated requirement, for future sustainable developments.
Recent Chronicle issues (“Back to the Trenches,” News, Dec. 16; “Saying ‘No’ to AMD,” News, Dec. 23, and “AMD Sets Its Site on Lantana,” News, Dec. 23; and “Blame It on Grandpa,” News, Dec. 30) seem to predict the imminent demise of the Edwards Aquifer should AMD proceed. Examination of satellite imagery and geologic maps shows that most of the land in the local Edwards Aquifer direct recharge zone has already been extensively developed. This includes the south MoPac corridor, Barton Hills neighborhood, Barton Creek Mall, Travis Country subdivisions, the huge malls in Sunset Valley, and the sprawling residential subdivisions south of 290. All of these lie directly atop the Edwards Aquifer, which regionally flows northward to Barton Springs. The Edwards Aquifer contributing zone is similarly developed, particularly along highways 290 and 71. Assuming these existing high-density developments have not already ruined the aquifer and Barton Springs, I doubt that development of the AMD tract (especially as proposed) and the few remaining parcels in the vicinity will have significant additional impact. Dye-tracer studies have shown that surface runoff from Lantana will likely re-emerge at Cold Springs on Town Lake, thereby bypassing Barton Springs entirely. Hence, notional arguments of ruinous follow-on secondary development and pollution appear to be specious. Further, Freescale Semiconductor’s large (1.5 million-square-foot) headquarters with 2,700 employees directly adjacent to the Lantana tract would seem to set a precedent for such development. In short, the proverbial horse has already long left the barn in terms of discouraging development directly on the aquifer and in the contributing zone. It seems that an opportunity has presented itself to use the AMD approach to create a model, an expected standard, perhaps even a mandated requirement, for future sustainable developments.
Douglas Watkins
Exploration geologist
Exploration geologist
