Southern Portion of the Carrizo-Wilcox Aquifer Groundwater Availability Model (GAM)
In 2019, the Texas Water Development Board (TWDB) contracted with GSI Environmental, Inc. to update the groundwater availability model of the southern part of the Carrizo-Wilcox, Queen City, and Sparta aquifers in Texas. The final report and model were released in April 2023.
Groundwater Management Area 13 contracted with Dr. Bill Hutchison (independent groundwater modeling consultant) to update v3.01 of the southern portion of the Carrizo-Wilcox, Queen City, and Sparta aquifers groundwater availability model. This updated model (v3.1) was released in January 2026.
Model Files and Associated Data
Please see the GAM files download page for the current model files and associated data.
Aquifer data is only available as a package for the entire model area and requires GIS software for processing. Please see the GAM files download page for aquifer data.
Stakeholder Advisory Forums (SAF)
Send us an email if you would like to receive SAF notifications.
| ID | Date | Location |
|---|---|---|
| SAF 1 | 8/2/2019 | Pleasanton, Texas | SAF 2 | 3/4/2021 | Online meeting (video) | SAF 3 | 7/22/2022 | Pleasanton, Texas |
Model Report (2004, v. 2.01)
"Groundwater Availability Models for the Queen City and Sparta Aquifers."
"TWDB Response to Stakeholder Comments and Questions."
Model Report (2003)
We are listing the 2003 report above as a resource on the conceptual analysis and data for the Carrizo-Wilcox Aquifer, an aspect that was not addressed by the 2004 GAM report.
Other Resources
Please see the Carrizo-Wilcox, Sparta, and Queen City aquifer pages for other reports and publications.
For model runs see the GMA 13 page.