Austin launches final year of program to combat toxic algae

Austin will undertake the fifth and final year of its pilot program to combat harmful blue-green algae in Lady Bird Lake on Monday. The city has dealt with toxic algae blooms every year since 2019, which have resulted in the death of six dogs and pose health risks to humans, including nausea and headaches. City officials first identified signs of potentially toxic algae in April and plan to apply lanthanum-modified bentonite at three lake sites to reduce phosphorus levels, a key nutrient for algae growth. Brent Bellinger, conservation program supervisor, indicated that while results have been mixed, Red Bud Isle has seen a significant drop in phosphorus levels, potentially limiting algal growth. The program costs $300,000 annually and is funded through utility drainage charges.

The lanthanum-modified clay binds to phosphorus, making it unavailable to algae, which may help reduce its food sources. Residents can further assist by limiting fertilizer use and cleaning up after pets. Researchers will collect data next year to gauge the effectiveness of the sediment response without new lanthanum applications.