Region
Texas
25
Trinity River Watershed
11
Richland-Chambers Reservoir (Tex.)
2
San Antonio
2
Trinity River Watershed (Tex.)
2
Dallas Region
1
Edwards Aquifer
1
Edwards Aquifer (Tex.)
1
Edwards Plateau
1
El Paso Region
1
Guadalupe River Watershed
1
High Plains Aquifer
1
Mesilla Valley
1
Nebraska
1
New Mexico
1
Nueces River Watershed
1
Rio Grande Valley (Colo.-Mexico and Tex.)
1
San Antonio River Watershed
1
Texas Panhandle
1
Trinity Aquifer (Tex.)
1