The Edwards Aquifer: The Past, Present, and Future of a Vital Water Resource
CONTAINS OPEN ACCESS

The Edwards aquifer system is one of the great karstic aquifer systems of the world. It supplies water for more than 2 million people and for agricultural, municipal, industrial, and recreational uses. The Edwards (Balcones Fault Zone) Aquifer in the San Antonio, Texas, area was the first to be designated a sole source aquifer by the Environmental Protection Agency in 1975. The Edwards Aquifer also hosts unique groundwater, cave, and spring ecosystems. This 27-chapter memoir reviews the current state of knowledge, current and emerging challenges to wise use of the aquifer system, and some of the technologies that must be adopted to address these challenges.
The use of water from the Edwards Aquifers, Texas Available to Purchase
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Published:September 10, 2019
ABSTRACT
Both people and the environment require water. The environment in Texas depends upon water discharged from the Edwards Aquifers, including ~1.5 million megaliters per year (ML/yr) from the Edwards-Trinity (Plateau) Aquifer and ~1 million ML/yr from the Edwards (Balcones Fault Zone) Aquifer. The first people in the area used the aquifer springs as drinking water and subsequently irrigated with the springs’ flow and then began drilling and pumping wells. Well production in the Edwards (Balcones Fault Zone) Aquifer was ~120,000 ML/yr in the 1930s and steadily increased over the next three decades to ~500,000 ML/yr, which is the average use from 1970 to 2015. Production from the Edwards-Trinity (Plateau) Aquifer was ~250,000 ML/yr from 1984 through 2016, while production from the Edwards-Trinity (High Plains) Aquifer was ~25,000 ML/yr from 1984 through 2016. The Interstate 35 growth corridor, extending from Bexar County (San Antonio) through New Braunfels, San Marcos, and Austin, Texas, and up to Bell County, is expected to grow from 4.6 million people in 2020 to 8.7 million in 2070. Despite the needs of this growing population, groundwater availability and regional water planning information suggests that pumping from the Edwards (Balcones Fault Zone) Aquifer over the next 50 yr will be limited. Groundwater availability numbers suggest that pumping in the Edwards-Trinity (Plateau) Aquifer could double from current levels, although planning information currently projects a more modest increase. Unsettled groundwater law and climate change could also affect future levels of pumping.