Summer heat has brought toxic algae blooms back to Utah Lake. On June 9 the Utah Department of Environmental Quality (DEQ) issued a warning advisory for Provo Bay telling people not to swim or water ski, and to keep pets and livestock away from the water.
Last summer toxic algae occurred in Utah Lake as well as eight Utah reservoirs, the Jordan River and Ogden City 21st Street Pond.
Toxic algae blooms are caused by nitrogen and phosphorous that wash into lakes and streams from fertilizer on agricultural land and lawns as well as manure and leaking sewage systems.
In 2010 there were just three reports of toxic blooms. In 2017 there were 169 reports nationwide including one that covered 700 square miles of Lake Erie. A new report from the Environmental Working Group says that the number of toxic blooms in the U.S. is increasing as a result of global warming.
Harmful Algal Blooms (Utah DEQ)