3 days ago
City of Austin continues to treat toxic blue-green algae in Lady Bird Lake
The Brief
Toxic blue-green algae is back in Lady Bird Lake
The City of Austin is still treating the algae that blooms in parts of Lady Bird Lake
The harmful algae was first documented in 2019 and has happened every year since then
AUSTIN, Texas - If you noticed the water in Lady Bird Lake looks a bit cloudy on Monday evening, that's because the city is treating toxic blue-green algae.
That algae, called cyanobacteria, has killed several dogs over the past few years.
The backstory
"We don't want [our dog] in the water. In the wintertime, he got in the water over here and loving it. We can't do that anymore," Tracy Bruce, who was at Red Bud Isle, said.
"We've changed how we walk. There's a couple of places up there where there's fish that he likes to get into and drink water, and so we are skipping that part of the trail," Mark Davis said.
The Austin Watershed Department is in the last year of a five-year pilot program to treat toxic blue-green algae blooms on parts of Lady Bird Lake.
The pilot program involves spraying lanthanum-modified clay in parts of the lake. The lanthanum molecule added to the clay binds to phosphorus, a key source of nutrients for the algae.
"The hope is that it'll reduce their growth and toxicity," Brent Bellinger, conservation program supervisor with the Watershed Protection Department, said.
The treatment has been helpful in Red Bud Isle.
"We've seen good changes in the phosphorus dynamics," Bellinger said. "The hope is that you can push the system back to what it was before the toxigenic algae were present."
However, downriver, changes have been smaller.
The pilot program costs $300,000 a year and is funded through a drainage charge on utility bills.
Experts collect data on toxicity, water quality, and more to decide what to do next.
"We'll put all of this together and look at and try to make some determinations about the overall efficacy of the product of this treatment. We'll weigh that against the costs. Then we'll look at other strategies," Bellinger said.
Why you should care
The harmful algae was first documented in 2019 and has happened every year since then.
Austinites can do their part to reduce toxic algae by using less fertilizer and picking up after their pets. However, there are also upstream contributors, like fertilizers, leaking septic takes, and treated wastewater effluent.
Make sure your dogs rinse off if they get in water. Toxins are more likely if the water is warm and stagnant.
"I'm really not worried about the blue-green algae so much, especially because we have more of a tendency to go to areas that have flowing water," dog owner Kwesi Coleman said.
There will be two more treatments in July and August.
If a person has sudden, unexplained symptoms after swimming, they should contact their medical provider or the Texas Poison Control Center at 1-800-222-1222. For a pet, they should contact their veterinarian. Please also let the city know by completing this reporting form, found at
The Source
Information from interviews conducted by FOX 7 Austin's Angela Shen
