text: The environmental conditions of the springs gave birth to a local political movement called the Save Our Springs Alliance (SOS).  SOS became a force in Austin municipal politics, leading to many "green" initiatives involving environmental issues in addition to those of the springs.
  Robert Redford, who first learned to swim at Barton Springs Pool, has also been an outspoken ally. In 2007 he and Terrence Malick co-produced The Unforeseen, a documentary highlighting environmental impact to the Edwards aquifer from the surrounding real estate subdivision.
  Another environmental issue involving the springs and the pool emerged with the discovery of the Barton Springs salamander, a federally listed endangered or threatened species which only exists in the pool and a few surrounding environs. After some debate, and studies by the city of Austin, Texas state agencies, and the U.S. Fish and Wildlife Service, it was determined that swimmers and salamanders could co-exist (as they had probably been doing for some time).
  The pool was also closed in 2003 after a cover story in a local paper claimed that the waters were toxic. After closing the pool for 90 days, officials from the CDC, USEPA, State of Texas and the City of Austin deemed it safe for swimmers. Ironically the source of the chemicals entering the pool were from a pavement sealer used on a nearby local parking lot. This discovery led to the nation's first ban of coal tar pavement sealers in 2005.