New test results from Lake Travis indicate a significant decline in the toxicity of blue-green algae, and for the first time since the spring, only trace amounts of the toxins were present, according to a June 22 update from the Lower Colorado River Authority.
Algae samples collected June 10 from the Travis Landing region of the lake reported a low concentration of cyanotoxins, the toxins produced by cyanobacteria or blue-green algae. While cyanotoxins were still present, the LCRA said the toxicity was below quantifiable levels.
LCRA began conducting routine testing near Travis Landing in February when officials received a report that a dog died after swimming in the lake. In March, a second dog had died and five others became ill, according to a previous update. Prior to the June 10 test results, every sample taken from that region contained possible dangerous cyanotoxin levels.
Despite the improvement, the LCRA is still urging lakegoers to avoid contact with algae and to keep their dogs from ingesting or playing near aglae in the Highland Lakes. Algae species capable of producing toxins are still present in Lake Travis.
All algae species should be treated as if it may produce harmful toxins since its toxicity can only be determined through laboratory testing. Additionally, the toxicity of an algae bloom can quickly change, according to the LCRA.
“It’s good to see those toxicity levels fall, but this is no time to let your guard down,” John Hoffman, LCRA executive vice president for water, said in a press release. “Conditions can change rapidly, and blue-green algae can be harmless one day and harmful the next.”
As Texas moves into its warmer summer months, the risk of harmful algae blooms only increases. Arid weather conditions, high temperatures and stagnant water can contribute to the growth of cyanobacteria, which the LCRA said are naturally occurring species within the Highland Lakes.
As of July 1, the LCRA will expand its routine mountaineering to include 16 additional sites in Lake Buchanan, Inks Lake, Lake Lyndon B. Johnson, Lake Marble Falls and Lake Travis.