Southern Portion of the Carrizo-Wilcox Aquifer Groundwater Availability Model (GAM)

This map shows the extent and location of the southern portion of the Carrizo-Wilcox Aquifer 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. A final report and model will be released in late 2023.

Draft Numerical Model Report

The Draft Final Numerical Model report and model files for the Southern Carrizo-Wilcox, Queen City, and Sparta Groundwater Availability Model update are available for Stakeholder review. Please submit written comments to Jean Perez before Monday, October 31, 2022.

General Use Disclaimer: The following model files were developed for regional scale use only and should not be used for local scale or individual site locations. The file sets are currently intended only for public review prior to the new DRAFT Groundwater Availability Model for the Southern Portion of the Carrizo-Wilcox, Queen City, and Sparta Aquifers being released as an official GAM. Furthermore, the files are released on condition that neither the TWDB nor the State of Texas shall be held liable for any damages resulting from its authorized or unauthorized use.

Draft Conceptual Model Report

Draft Conceptual Model Report: Update to the Groundwater Availability Model for Southern Portion of the Carrizo-Wilcox, Queen City, and Sparta Aquifers.

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 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.

Model Report (2003)

"Groundwater Availability Model for the Southern Part of the Carrizo-Wilcox Aquifer in Texas (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.