Austin lakes ranked in top 10 worst places for toxic algae: study

Lady Bird Lake ranked on toxic algae list

Lady Bird Lake and Lake Austin were both ranked in a new study naming the top 10 places with the worst toxic algae blooms in the world.

AUSTIN, Texas - When it's a bit warmer outside, Lady Bird Lake is one of most well known spots to go kayaking and paddleboarding, but according to a new report, you might want to think twice next time you set sail.

"I would personally not swim in a bloom or paddle board in a bloom," said Jan Spin, the president of BlueGreen Water Technologies.

A bluish-green foamy gross mess often floated on top of Lady Bird Lake this summer.

"It is an important part of the environment, but sometimes it can go rogue and unchecked, and when it does that it will then dominate the ecosystem that it's in, and that's when it becomes a problem," said Spin.

Spin is with BlueGreen Water Technologies, a company that said it's focused on improving and preserving water quality.

Toxic algae detected in Lakes LBJ and Inks

The Lower Colorado River Authority says they have detected toxic algae at levels that could pose a danger to dogs and people in Lakes LBJ and Inks. The toxicity was detected only in the algae, not in the lake water.

This year, "Lady Bird Lake" and "Lake Austin" ranked eighth on its top ten list for the worst toxic algae blooms in the world.

"We look at the percentage of the infection, let's say, we look at the proliferation of the bloom," said Spin. "Is this something that's growing year on year? We also look at if the community is taking an active approach to addressing it and Austin is taking an active approach to try to address the matter."

Since 2021, Austin has been treating the water, trying to reduce the amount of phosphorus available to help the toxic algae grow.

But, Spin said warmer temperatures, high levels of CO2, and nitrogen, which acts like a fertilizer, may make stopping the bloom more challenging.

"Those three elements combined together creates the perfect environment for the algae to thrive," said Spin.

The algae can be harmful, including to people and their pets.

In past years, there has even been multiple reports of dogs who died after jumping in the water.

"We would like to encourage everyone to be alert, to take precautions," said Spin. "Note your local listing, and also at the end of the day these harmful algae blooms are not just an Austin issue. It's a global issue."

In the meantime, spin recommends staying away from areas of the lake where you see toxic algae and to report it.

Austin’s Watershed Protection Department sent Fox 7 the following statement:

"It is not clear to us what metrics or data were used in creating this list. Unlike many places, Austin has not had to close our lakes to recreation due to harmful algae, and we’re not aware of any illnesses associated with harmful algae on our lakes this year. It is true that mats of harmful algae have been present in the Austin area since at least 2019, with initial testing done on Lady Bird Lake.

It is difficult to compare Austin’s experience with other places since the type of algal growth form is different. In Austin, the algae mats begin on the bottom of the lake and float to the top, making their distribution very patchy. In other places, algae tends to take the form of individual cells spread throughout the water body, called a planktonic bloom. A planktonic bloom poses a greater risk to people and pets.

Not much is known about the mats of harmful algae that we’ve been experiencing. The City of Austin has been expanding our monitoring of the lakes, springs, and creeks; partnering with other agencies to share data and knowledge; and conducting studies to learn more about the extent of the algae and the conditions where it is likely to thrive and pose the most risk."