The Edwards Aquifer is one of the major groundwater systems in Texas.  It has been a source of water for people in south central Texas for more than 12,000 years.  Today, it is the primary source of water for approximately 1.7 million people.

The Edwards Aquifer is one of the world's unique groundwater resources, extending 180 miles from Brackettville in Kinney County to Kyle in Hays County. While it is our primary source of water, it is the sole-source of water for a unique system of aquatic life, including several threatened and endangered species. Cities, towns, rural communities, and farm and ranch lands all depend on the aquifer's water for household, agricultural, industrial and recreational purposes. The diversity of uses illustrates the importance of the aquifer to the lives and livelihoods of residents in the Edwards Aquifer region.

For years, it was thought the Edwards Aquifer was a never-ending supply of fresh drinkable water. In 1940, the region was pumping 120,000 acre-feet of water or 39 billion gallons, a year. But in the 1950s, a seven-year drought drastically lowered water levels in the aquifer. In the 1980s and 1990s, droughts of shorter duration occurred, requiring heavy pumping from wells. Also, average pumping from Edwards wells has increased dramatically in the last five decades because of population growth and demand. In San Antonio alone, population has increased from about 200,000 people in 1940, an estimated 17 million in 2000. Populations of other communities in the region, such as Uvalde, Hondo, New Braunfels, and San Marcos have also grown. In 1989, regional pumping reached a maximum of 542,000 acre-feet of water per year - more than 175 billion gallons. In the 1990s, the amount of aquifer water pumped ranged from 327,000 acre-feet in 1992, to 493,000 acre-feet in 1996. Median springflow discharge from 1934 to 2004 is 383,900 acre-feet a year.

Water resource planners project by the year 2020 demand for water in the Edwards Aquifer region could be 863,000 acre-feet per year or more than 275 billion gallons. Median recharge recorded from 1934 to 2004 at 560,900 acre-feet per year will not keep up with this demand. Recharge is entirely dependant on rainfall. Therefore, during drought periods less recharge is available to meet ever-increasing demand.

The Edwards Aquifer will continue to be the primary source of water for the region. Various groups and entities in the Edwards Aquifer region have undertaken the difficult task of addressing present and future water needs. The need for planning is continuous. The need for stewardship is essential. The need for management is critical.

The first known reference to the Edwards Aquifer groundwater resource was made in 1898 when geologists Robert Thomas Hill and Thomas Wayland Vaughn hypothesized that the Edwards limestone was water bearing. They also established the Edwards limestone name to define the rock from other formations in the area. Edwards limestone was first discovered in Edwards County which was named for Hayden Edwards, the "empressario of West Texas" in the 1820's. In the 1930's it was known as the groundwater resources of the Edwards limestone. The Edwards Aquifer began to formally get its identity in the late 1950's when the Texas Board of Water Engineers (now the Texas Water Development Board) called it the Edwards Underground Reservoir. Over time, the name gradually became the Edwards Aquifer.