Barton Springs Pool is a man-made recreational swimming pool located on the grounds of
in Austin, Texas. The pool exists in the channel of Barton Creek and is filled by water from Main Barton Spring, the fourth largest spring in Texas.
There is improved sidewalk access along the shorelines, but the bottom of the pool and some of the walls are natural rock.
The pool is usually open to the public from 5:00am to 10:00pm, Friday through Wednesday. During this time, the floodgates on the pool's dam are closed, and Main Barton Spring fills the pool to a maximum depth of more than 18 feet. At the upper end of the pool, another dam prevents surface water from Barton Creek from entering the pool by diverting it through a tunnel under the sidewalks.
Although admission to the pool is free from November through mid March, from mid March to October a small fee ($1 to $3) is charged for entry after 8:00am. Every evening after 9:00pm during the charging season, admission is free until closing. Summer passes, valid from Memorial Day to Labor Day, are also available.
Lifeguards are usually present except before 8:00am, when swimmers are cautioned to "swim at your own risk". The pool is surrounded by grassy slopes which are ideal for sunbathing. Topless sunbathing is permitted, as in the rest of Austin. Items prohibited from entering the facility include coolers, food, non-resealable beverages other than water, glass containers, alcohol, loud speakers, pets other than service animals, and bicycles. Floatation devices are permitted at either end of the pool, but not allowed in the middle.
On Thursdays, the pool is closed for cleaning from 9:00am until 7:00pm. The floodgates are sometimes partially opened, lowering the water level in the pool by several feet. Employees then buff or blast pressured water against the limestone bottom of the pool's shallow end, as well as the steps and ramps leading into the water, in order to wash away the hazardous and slippery algae buildup. In the deep end, a fire hose is used to push debris toward the downstream dam. Overgrown vegetation is also trimmed on cleaning days. Once a year the pool is closed for several weeks for more extensive cleaning.
The pool is closed during flash flood warnings as Barton Creek may flood and overflow the diversion dam. Swimming in Barton Springs Pool is then unsafe, as it transforms into a raging creek. The pool is then closed for several days after a flood, so mud and debris that washed into the pool can be removed. Other unplanned reasons for pool closure include lightning or thunder in the area, "search and rescue" situations, serious medical emergencies, high fecal coliform count, and chemical spills (either inside the pool itself or over the Barton Springs segment of the Edwards Aquifer).