Edwards Aquifer

1 states · 10,360 sq km · karst
High Depletion Risk

About the Edwards Aquifer

The Edwards Aquifer is a highly productive karst aquifer in south-central Texas that serves as the sole source of drinking water for San Antonio and surrounding communities. Its rapid recharge and discharge make it both prolific and vulnerable.

Area
10,360 km²
Depth Range
400–1,000 ft
States
1
Rock Type
Limestone (karst)

Key Facts

  • Sole source of drinking water for San Antonio (until recent diversification)
  • Comanche Springs and San Marcos Springs are among the largest in Texas
  • Designated a 'sole source aquifer' by the EPA
  • Subject to strict withdrawal limits during drought
  • Home to several federally protected endangered species

States Overlying the Edwards Aquifer

Explore Water Assets Over the Edwards Aquifer

See every tracked spring, well, and water right that draws from this aquifer on our interactive map.

Open Map Explorer

Other Major Aquifers