Algae Covers 20 to 25% of Lake’s Surface at Red Bud

In early September, the situation appeared to be improving with the amount of algae declining and test results showing no toxins, but as of late September, algae is covering one-fourth of Red Bud’s surface at Lady Bird Lake.

A harmful algal bloom containing neurotoxins has been detected in some algae on Lady Bird Lake.

AUSTIN, TX—Cyanobacteria is also called blue-green algae and is common in Austin. There are many types of blue-green algae and some can produce harmful toxins called algal bloom. Some produce dangerous toxins in fresh or marine water but even nontoxic blooms hurt the environment and local economies.

Blue-green algae tends to be more prevalent in late summer and early fall. It thrives when temperatures are hot, nutrients are high and flow is low. Zebra mussels, flooding during the fall and climate change are potential contributing factors.

In July, the city confirmed an algal bloom on Lady Bird Lake, where neurotoxins have been detected in some algae. Austin Water regularly looks at algae levels on Lake Austin and Lake Travis, and has not detected levels of concern for drinking water. Currently, Austin Water does not use Lady Bird Lake as a source for drinking water.

The city initially tested water samples and algae from eight locations on Lady Bird Lake. Additional samples were taken at the Walsh Boat Ramp on Lake Austin and downstream of Longhorn Dam. The city is currently testing water and algae at three locations on a weekly basis.

After the initial testing, toxins were also detected in algae at Red Bud Isle, Auditorium Shores and Barton Creek. Specifically, on September 24, testers noted a sudden increase in algae at Red Bud Isle but lower levels of toxins in this new batch of algae. Earlier in September, the situation appeared to be improving with the amount of algae declining and test results from September 9 showing no toxins. However, as of late September, algae is covering about 20 to 25% of the water surface at Red Bud.

This second wave of algae is not unexpected given the unrelenting heat, less flow through the lakes and the natural life cycle of algae. The city says it has not identified an effective and safe way to treat or remove the algae but says it will naturally die off when cooler temperatures and higher flows return in the fall.

City officials warn that the lake is not safe for pets at this time. There have been reports of five dogs that have died after swimming in Lady Bird Lake this summer. The city cautions it is not safe for pets to drink from or swim in Lady Bird Lake or parts of Barton Creek near the lake.

Other warnings: Do not handle the algae and generally, minimize contact with the water in Lady Bird Lake. Remember that swimming is prohibited in Lady Bird Lake (ord. 640611-C).

Avoid creeks and lakes where the water is warm and stagnant or where there is a lot of algae present. Boating and paddle boarding are allowed at each person’s own risk. City officials recommend that people and dogs rinse off if they are in contact with the water. If symptoms occur, seek immediate medical attention.

Toxic algae expert Eyal Harel is the CEO and co-founder of BlueGreen Water Technologies Ltd. and an authority on the root causes of the toxic algae epidemic. He recently shared his perspectives on the impact on surrounding real estate.

“Algal blooms release toxins and change the water chemistry until in extreme cases, they render the water a ‘dead aquatic zone’,” Harel tells GlobeSt.com. “Under bloom conditions, the use of the water is prohibited for drinking and recreation, and the produce of the water, i.e., fish, should also be considered as toxic. If not treated, blooms will continue to intensify on an annual basis. This will have dire consequences on the entire economical eco-system that depends on the water. More importantly, as toxins become airborne, they directly endanger the health of adjunct communities.”

Harel says this means that fewer people would be likely to engage in commercial activity in and around an infected lake.

“While at the same time, fewer people desire to buy a property that can prove to be a health hazard if located too close to such a lake,” he tells GlobeSt.com. “As a single, rather small example, the losses in real estate value next to Buckeye Lake on 3,173 acres in Ohio in the last five years are estimated at $100 million.”

Young children, older adults and those with medical conditions are more vulnerable to the possible health effects as a result of algae exposure. City officials advise these populations to take extra precautions and pay attention to possible signs of harmful algae bloom-associated illness.

Symptoms include rash, irritation, swelling or sores; gastrointestinal signs or symptoms, respiratory signs or symptoms, fever, headache, neurologic signs or symptoms, ear symptoms and eye irritation. Austin Public Health routinely tracks emergency department visits and has not reported any increases in unusual conditions that may be related to exposure to the water.