119 Recent Investigations of the Hydrogeology Edwards (Balcones Fault Zone) Aquifer, the Trinity (Hill Country) Aquifer, and Their Interactions, South-Central Texas

Recent research into the hydrogeological characteristics of the Edwards (Balcones Fault Zone) and/or Trinity (Hill Country) aquifers, south-central Texas, including their inter-aquifer connections, vulnerability, and prospects for long-term sustainability given changes in population, land use, and climate of the region.

Monday, 20 October 2025
1:30 PM - 5:30 PM
HBGCC, 209

Participants

• Chair F. Paul Bertetti
• Chair Yongli Gao
• Chair Brian Smith
• Chair Allan Clark

Presentations

• 1:35 PM
  Geologic Framework and Hydrostratigraphy of the Edwards and Trinity Aquifers Within Parts of Bandera and Kendall Counties, Texas
  Allan Clark, San Antonio, San Antonio, Texas
  412698 (Technical Sessions)
• 1:50 PM
  Importance of Allogenic versus Autogenic Recharge to the Karstic Edwards and Hill Country Trinity Aquifer System, Texas
  Ronald Green, Southwest Research Institute, San Antonio, Texas and F. Paul Bertetti, Edwards Aquifer Authority, San Antonio, Texas and John Sharp, The University of Texas, Austin, TX and Brian Hunt, Bureau of Economic Geology, Austin, Texas
  412680 (Technical Sessions)
• 2:10 PM
  New Insights on the Karstic Barton Springs Complex from Multiport Well Data, Austin, Texas.
  Jeffery Watson, BSEACD, Austin, Texas and Justin Camp, BSEACD, Austin, TX and Jacob Newton, BSEACD, AUSTIN, TX and Samuel McKinney, The City of Austin, Watershed Protection Department, Austin, TX
  414482 (Technical Sessions)
• 2:25 PM
  Quantifying Recharge Basin Contributions to Springflow in a Karst Aquifer Using Solute Transport Modeling
  Changbing Yang, Edwards Aquifer Authority, San Antonio, TX and F. Bertetti, Edwards Aquifer Authority, San Antonio, TX and Hakan Başağaoğlu, Edwards Aquifer Authority, San Antonio, TX
  413133 (Technical Sessions)
• 2:40 PM
  Mapping the geology, structure, hydrostratigraphy, and potential habitat of Streptanthus bracteatus (bracted twistflower )
  Chris Best, Austin, Austin, Texas and Allan Clark, San Antonio, San Antonio, Texas
  412752 (Technical Sessions)
• 2:55 PM
  Revisiting Puente 1978: Interpreting the foundational Edwards Aquifer recharge dataset in light of contemporary understanding of Edwards-Trinity interactions
  Logan Schmidt, The Edwards Aquifer Authority, San Antonio, TX and Changbing Yang, The Edwards Aquifer Authority, San Antonio, TX and F. Paul Bertetti, Edwards Aquifer Authority, San Antonio, Texas
  414031 (Technical Sessions)
• 3:25 PM
  The Edwards -Trinity Connection: What We Believed, What We Know, and What Gaps Remain
  George Veni, George Veni and Associates, Carlsbad, New Mexico
  414198 (Technical Sessions)
• 3:45 PM
  Hydraulic Characterization of the Lower Trinity Hosston Aquifer in Central Texas Using Available Municipal Data, Well Hydraulics and Water Level Monitoring
  Connor Weatherly, Baylor University, Waco, Texas and Joe Yelderman, Baylor University, Waco, Texas and Wayne Hamilton, Baylor University, Waco, Texas
  413676 (Technical Sessions)
• 4:00 PM
  Assessing the vulnerability of the Edwards and Trinity aquifers in areas where they are hydraulically connected
  Jessica Quintanilla, Edwards Aquifer Authority, San Antonio, Texas and Karen Mendiondo, Edwards Aquifer Authority, San Antonio, Texas and Brennan Romero, Edwards Aquifer Authority, San Antonio, Texas and Gizelle Luevano, Edwards Aquifer Authority, San Antonio, Texas and Brent Doty, Edwards Aquifer Authority, San Antonio, Texas and F. Bertetti, Edwards Aquifer Authority, San Antonio, Texas
  414024 (Technical Sessions)
• 4:15 PM
  Multi-Isotope Characterization of Edwards and Trinity Aquifer Interactions along the Balcones Fault Zone and the Hill Country
  Michael Weathers, University of Texas at San Antonio, San Antonio, TX and Yongli Gao, University of Texas at San Antonio, San Antonio, TX and F. Paul Bertetti, Edwards Aquifer Authority, San Antonio, TX and Rebecca Nunu, Edwards Aquifer Authority, San Antonio, tX and Jessica Quintanilla, Edwards Aquifer Authority, San Antonio, TX and Lin Ma, University of Texas at El Paso, Dept of Geological Sciences, El Paso, TX and Richard Edwards, University of Minnesota, Geology & Geophysics, Minneapolis, MN
  414007 (Technical Sessions)
• 4:30 PM
  PFAS and Water Quality Indicators of Aquifer Vulnerability in the Edwards–Trinity System
  Stephen Hernandez, The University of Texas at San Antonio, San Antonio, TX and Claire Ong, The University of Houston, Houston, TX and Amna Afzal, The University of Houston, Houston, TX and Michael Weathers, The University of Texas at San Antonio, San Antonio, TX and F. Paul Bertetti, Edwards Aquifer Authority, San Antonio, TX and Qi Fu, The University of Houston, Houston, TX and Yongli Gao, The University of Texas at San Antonio, San Antonio, TX
  413674 (Technical Sessions)
• 4:45 PM
  Impacts of the current drought on the Edwards and Trinity aquifer systems: Are there implications for the future?
  F. Paul Bertetti, Edwards Aquifer Authority, San Antonio, Texas and Rebecca Nunu, Edwards Aquifer Authority, San Antonio, Texas
  414268 (Technical Sessions)
• 5:00 PM
  Assessing Long-Term Changes in Spring Water Chemistry Using Weighted Regression on Time, Discharge, and Season (WRTDS) at Barton Springs, Edwards Aquifer (1995–2025)
  Michael Markowski, City of Austin, Austin, Texas and Joaquina Guevara, City of Austin, Austin, Texas and Tyson McKinney, City of Austin, Austin, Texas and Meghan Slocombe, City of Austin, Austin, Texas and Lindsey Sydow, Watershed Protection Department, Austin, Texas and Dana Thomas, City of Austin, Austin, Texas
  413500 (Technical Sessions)