Deep Glen Rose Formation in South Texas (the 'Maverick Basin' aquifer)
Image source: Railroad Commission of Texas, Groundwater Advisory Unit
Summary
The Groundwater Advisory Unit of the Railroad Commission of Texas recently identified and partially mapped a deep portion of the Glen Rose Formation in Maverick, Zavala, Dimmit, Kinney, and Uvalde counties that could be a potential source of freshwater for local communities. The aquifer currently has a working name of the Maverick Basin aquifer. Fresh groundwater is reported at depths between 5,000 and 8,000 feet below land surface.
The TWDB is working with the Railroad Commission of Texas and other entities, like the UT Bureau of Economic Geology and the Texas Water Resources Institute, who have researched this aquifer to assemble and evaluate available data on the occurence and characteristics of this possible aquifer. Additional data and information will be posted on this webpage as it becomes available.
What we currently know
- Aquifer type: confined transborder aquifer with artesian flow
- Formation: Glen Rose Formation, Trinity Group
- Depth: greater than 5,000 feet
- Area of aquifer in Texas: at least 3,000 square miles
- Recharge zone: believed to be 50 miles west of the Rio Grande in Mexico
Status update
- March 2022: TWDB BRACS staff are incorporating the Maverick Basin aquifer in their study of brackish groundwater resources in the Edwards-Trinity (Plateau) area. Currently, BRACS staff are identifying geophysical logs in the Glen Rose Formation in Maverick and surrounding counties, depth-calibrating the logs to incorporate with geologic mapping software, and interpreting stratigraphic surfaces on these logs.
Resources
- Railroad Commission of Texas news release
- Railroad Commission of Texas presentation on the Deep Glen Rose Formation
- Journal of Hydrology Article: Transboundary aquifers between Chihuahua, Coahuila, Nuevo Leon and Tamaulipas, Mexico, and Texas, USA: Identification and categorization
- Texas Groundwater Protection Committee White Paper: Transboundary Groundwater Resources along the Texas-Mexico Border
TWDB Reports
| ID | Date | Type | Description |
|---|---|---|---|
| GMR17-01 | April 2017 | Groundwater Management Report | Transborder Aquifers: A Summary of Aquifer Properties, Policies, and Planning Approaches for Texas, Surrounding States, and Mexico |
| LP-214 | February 1995 | Limited publication | Evaluation of Ground-Water Quality in Texas Counties Bordering the Rio Grande |
| 5617 | December 1956 | Bulletin | Records of Water-Level Measurements in Dimmit, Maverick, and Zavala Counties, Texas |
| 5203 | March 1952 | Bulletin | Winter Garden District Dimmit and Zavala Counties and Eastern Maverick County, Texas |
| M302 | 1940 | Historical Groundwater Report | Records of Wells, Winter Garden District, Dimmit and Zavala Counties and Eastern Maverick County, Texas |