Summary document (Fact Sheet 08-2017) of the major categories of District scientific studies and their implications for aquifer management. Compiled in honor of the District’s 30 year anniversary since it was created in 1987.

Recent groundwater studies reveal complex surface and groundwater interactions within the streams that link the Trinity and Edwards Aquifers of the Hill Country and Balcones Fault Zone. Current numerical models do not adequately account for these interactions. The purpose of this paper is to summarize recent studies within the Blanco…

Hydraulic conductivity is one of the defining characteristics of hydrostratigraphic units. Detailed and quantified permeability information from the units comprising the Edwards and Trinity Groups is lacking in central Texas. These rock groups comprise important karstic and fractured carbonate aquifers. To better manage water resources and understand fate and transport…

Onion Creek is an important hydrologic link between two major aquifers in Central Texas. Multiple small springs discharging from the Trinity Aquifers sustain base flow in Onion Creek, which in turn recharges the Edwards Aquifer, ultimately discharging at Barton and San Marcos Springs. The creek generally contains clear, low nutrient…

An overview of the District, water planning, available groundwater, groundwater resources, permitting, recharge, history of droughts and floods, and contact information.

The Cretaceous-age Edwards and Middle Trinity Aquifers of central Texas are critical groundwater resources for human and ecological needs. These two major karst aquifers are stratigraphically stacked (Edwards over Trinity) and structurally juxtaposed (normal faulting) in the Balcones Fault Zone. Studies have long recognized the importance of faulting on the…

Detailed geologic maps are the foundation for any geologic, hydrogeologic, and engineering studies. However, consistent, seamless, detailed geologic maps are lacking for central Texas. In order to manage its groundwater resources with the best available data the District has embarked on a long-term project to produce a digital seamless Geographic…

Pleasant Valley Spring (PVS) and Jacob’s Well Spring (JWS) are large karst springs providing perennial baseflow to the Blanco River and Cypress Creek, respectively, which eventually recharges the Edwards Aquifer. In order to better understand groundwater flow and sources of recharge to these springs (springsheds), we created a potentiometric map…

Leaking petroleum storage tanks from gas stations are one of the most common sources of contamination of groundwater in the U.S. and Texas. In 1992 a 2,900 gallon gasoline and diesel release occurred at the Big Wheel Truck Stop located on the highly sensitive Edwards Aquifer in Austin, Texas. The…

Pleasant Valley Spring (PVS) and Jacob’s Well Spring (JWS) are large karst springs providing perennial baseflow to the Blanco River and Cypress Creek, respectively, which eventually recharges the Edwards Aquifer. JWS flow has become intermittent in recent years due to drought and increased pumping driven by nearby population growth within…