Austin’s toxic algae pilot continues this summer

With warmer temperatures firmly in place, worries about toxic algae are, once again, on the minds of dog owners across the city. These concerns are shared by the city, which will continue its $300,000, five-year pilot that aims to reduce the dangerous algae blooms on Lady Bird Lake. The pilot uses lanthanum-modified clay, which binds to phosphorus in the lake, making it an unusable source of nutrients for the algae – depriving it of a primary food source. According to a press release from the city, the first application of the clay will take place in June, with additional applications in July and August. A contractor will be treating areas near Red Bud Isle, the north-shore boat ramp just west of Interstate 35 and the north shore of the lake between I-35 and the Festival Beach Boat Ramp (roughly).

Also according to the press release, the results of the first three years of the pilot have been “mixed.” It continues, “At Red Bud Isle, there has been a reduction in the amount of harmful algae after each application in June. The July and August applications appear to hold the line without achieving any further reduction of the algae. By the time following June and the first application of the year rolls around, the algae has generally returned. This year, the City of Austin observed a recurrence early in the spring, but the rains over the past two months have reduced its presence. There was not much present on the lakes in mid-May. East of I-35, the lanthanum-modified clay does not appear to be having any effect. This may be because new sediments from upstream areas are covering up the clay and bringing in more nutrients.” The press release notes that reducing the amount of nutrients that enter the lake “would likely be the most effective solution” and that Austin residents can help by avoiding or limiting fertilizers and landscaping with native vegetation, as opposed to lawns.