Barton Springs
Barton Springs are four natural water springs on the grounds of Zilker Park in Austin, Texas, formed by water flowing from the Edwards Aquifer. Main Barton Spring (also known as Parthenia, “the mother spring”), Austin’s main spring, gives water to Barton Springs Pool, a popular recreational attraction. The smaller springs are nearby, and two of them have man-made structures to contain and direct their flow. The springs are the only known home of the endangered Barton Springs Salamander.
In 1985, the National Archeological and Historic District of Barton Creek was established.
Geology
Barton Springs serves as the principal discharge point for the Edwards Aquifer of Texas, a well-known karst aquifer. The aquifer is formed of Cretaceous limestone that is around 100 million years old. In this limestone, fractures, fissures, conduits, and caves have formed. These gaps have been increased by both physical factors, such as faulting, and chemical forces, such as limestone disintegration by intruding water. As a result, a limestone karst aquifer with enormous vacuum spaces forms. Water then seeps into the aquifer, filling the gaps.
Rainfall is the source of all water spilling from Barton Springs. Some of this rain falls directly on the recharge zone, which is an area of land where the aquifer limestone rock is exposed. Other rainwater infiltrates the limestone bedrock via creeks that pass the recharging zone. Water enters the aquifer and flows along the gradients formed by hydraulic pressure differences into the area of lowest hydraulic pressure. Barton Springs is the hydraulic pressure’s lowest point.
Main spring
The most famous, but least visible, of the four springs is Main Barton Spring/Parthenia, which is fully submerged by pool water. The spring’s flow is not constantly visible at the surface of Barton Springs Pool’s diving board.
The main spring has an average daily flow of around 31 million US gallons (120,000 m3). During the 1950s drought, the lowest flow was 9 million US gallons (34,000 m3) per day, and the largest discharge was 85 million US gallons (320,000 m3) per day during the December 1991 floods. In example, a normal household swimming pool stores approximately 50,000 US gallons (190 m3), while the City of Austin, with a population of approximately 1 million people, uses approximately 120 million US gallons (450,000 m3) each day for its public water delivery system.
Other springs
Eliza, Old Mill, and Upper Barton Spring are the additional springs linked with Barton Springs. Each is much smaller than Main Barton Spring, with a daily discharge of 3 million US gallons (11,000 m3). These springs can sometimes dry up completely.
Eliza Spring, also known as Concession Spring, is located 300 feet (100m) east of the children’s playscape, near the north entrance to Barton Springs Pool. An amphitheater-style swimming area was constructed around the spring in the early twentieth century. Because of safety concerns and the fact that Eliza Spring has become a sensitive habitat area for the endangered Barton Springs Salamander, this structure is no longer open to the public.
On the south side of Barton Springs Pool, you’ll find Old Mill Spring, sometimes known as Sunken Gardens Spring or Zenobia Spring. The early twentieth-century structure built around Eliza Spring, like Eliza Spring, is currently closed to the public owing to safety and endangered species habitat concerns. Despite being less than a half-mile (800 m) away, the water at Old Mill Spring has a somewhat different chemical from that of Main Barton Spring and Eliza Spring, according to scientific investigation.
Upper Barton Spring is roughly a half mile (800 m) upstream or west of Barton Springs Pool in the creek bed of Barton Creek. Upper Barton Spring is frequently dry, but during floods it is completely covered by Barton Creek. Upper Barton Spring’s water likewise has a distinct chemical from the other springs.
The area surrounding Barton Springs is plagued with faults from the Balcones Fault Zone and is home to additional, smaller springs. An intermittent spring, for example, fills a popular natural swimming hole approximately a mile (2 km) upstream of Upper Barton Spring. Several more minor springs drain straight into the Barton Creek bypass tunnel, which runs alongside Barton Springs Pool.
Fauna
Barton Springs is home to two salamander species: the Barton Springs salamander and the Austin blind salamander.
Barton Springs salamander
The Barton Springs salamander (Eurycea sosorum) is a lungless salamander that is critically threatened. It is only found in Texas, the United States. It was discovered at Austin’s Barton Springs, but it is now also known from other locations in Travis and Hays Counties. Barton Springs is located in Zilker Park in Austin, Texas, on the Edwards Aquifer. Eliza Springs, which is a part of Barton Springs, features one of the most diverse populations of Barton Springs salamanders.
Austin blind salamander
The Austin blind salamander (Eurycea waterlooensis) is an endangered salamander in the Plethodontidae family that is only found in Barton Springs in Austin, Texas. It takes its name from Waterloo, Austin’s original name.
Austin blind salamanders, most of which are youngsters, have been spotted near spring exits. Its total number is unclear, however it appears to be significantly less abundant than the sympatric Barton Springs salamander (E. sosorum).
It is a paedomorphic, completely aquatic species (does not metamorphose).
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