AUSTIN (KXAN) — The City of Austin has detected blue-green algae toxins in Barton Creek at Sculpture Falls and is warning visitors the water isn’t safe for humans or animals.

Samples were taken on Sept. 9 after a report of human illness. Those results came back Wednesday. The toxin levels found are above U.S Environmental Protection Agency guidance for recreational use, according to the city.

City officials are advising that people and pets shouldn’t ingest or swim in the water. Signs will be posted at access points to the Barton Creek Greenbelt near Sculpture Falls to alert visitors.

The city said the type of toxin found at this site is called cylindrospermopsin. Officials point out it has different health effects compared to other toxins found in the past. Even further, the toxins were found in water samples rather than in the algae, which the city said increases the risk of exposure, especially in this popular swimming hole.

Cylindrospermopsin may cause liver and kidney damage, the city said. Health effects to humans and animals include:

  • Fever
  • Headache
  • Vomiting
  • Bloody diarrhea

The city asks you to seek medical help as soon as possible if you’ve been exposed. You can call 311 to report possible illness in people or pets from harmful algae.

Learn more about how to avoid toxic algae on the city’s website.