Austin warns swimmers and dogs as blue-green algae returns to Red Bud Isle
Austin TX – City officials say blue-green algae mats are back at Red Bud Isle and Walsh Boat Landing, prompting renewed caution for pets and swimmers.
Austin Watershed Protection is warning residents after thick mats of blue-green algae were observed near Red Bud Isle on Lady Bird Lake and at Walsh Boat Landing on Lake Austin. Officials say the caution is aimed especially at swimmers, shoreline users, and dog owners who may encounter visible algae.
City staff collected samples at six monitoring sites. The warning is a reminder that visible mats can turn up in more than one spot, and residents should treat what they see on the water or along the shore with caution.
What residents should do
The city advises people to avoid visible algae, keep dogs away from it, and rinse skin and pet fur after any contact with the water. Residents should also contact a medical provider or veterinarian if a person or pet develops sudden, unexplained illness after water exposure.
Why the 2026 response matters
Austin says 2026 is a control year in its algae pilot program, so there is no lanthanum-modified clay treatment this season. That makes this summer’s warning a useful update for lake users watching how the city handles algae without the treatment in place.
For anyone spending time on Lady Bird Lake or Lake Austin, the practical takeaway is simple: avoid visible mats, keep dogs out of them, and pay close attention to city guidance as summer heat pushes more people toward the water.
