The pool is open to the public every day except Thursday from 5 a.m. to 10 p.m. From mid-March through October, an entry fee ($2 to $5 for Austin residents, $4 to $9 for non-residents) is required from 8 a.m. until 9 p.m. Summer passes, valid from Memorial Day to Labor Day, are also available. Admission to the pool is free from November through mid-March. Lifeguards are on duty beginning at 8 a.m., and other hours are "swim at your own risk".
Prohibited items include • Alcohol • Food • Pets • Coolers, ice chests, or thermal bags • Glass • Frisbees, footballs, soccer balls or other hard balls • Portable speakers • Tobacco – smoking of any kind is not allowed Anyone seen smoking or with an open container of alcohol will be asked to leave or denied entry. Flotation devices are permitted at either end of the pool, but not in the middle section. When open for swimming, the floodgates on the pool's
dam are closed, and
Main Barton Spring fills the pool to a maximum depth of about 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. On Thursdays, the pool is closed for cleaning from 9 a.m. until 7 p.m. 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. The pool is closed for several weeks once a year 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). == Environmental issues ==