CARBON COUNTY, Utah -- The Southeastern Utah Public Health Department has issued a no swimming warning for Scofield Reservoir.
That's because toxic algae has bloomed in the popular fishing and boating spot in Carbon County.
Cyano bacteria has given the reservoir what looks like an oil slick on the top of the water.
The bacteria occurs when phosphorous and nitrogen come together and the sun warms it up.
"When that cyanobacteria gets out of control it kind of overwhelms the lake," Jared Mendenhall with the Utah Department of Environmental Quality said. "It starts to produce toxins and other things that are harmful to humans."
People can be sickened with a variety of skin, respiratory, neurological and abdominal symptoms.
For wildlife, livestock and pets, exposure to the toxic algae can be fatal.
"You`re going to want to keep pets and livestock away from the reservoir," Mendenhall said.
There's no timeline on how long the algal bloom will be present. Factors like heat and wind can either break it up, or make it worse.
"You just have to let it run its course,” according to Mendenhall.
Besides not going in the water, you're advised to wash all fish caught there before cooking, as well as any other food items that may have come in contact with the water.