As temperatures heat up, a familiar and potentially dangerous sight of summer is returning to Brownlee Reservoir.
The bright blue-green blooms of cyanobacteria have put on dazzling shows in satellite images of Lake Erie and other parts of the world.
But the algae is toxic to humans and animals.
Idaho Department of Environmental Quality officials say they’ve found high concentrations of the algae in a 15-mile stretch of the Snake River in Brownlee Reservoir.
They’ve issued a health advisory from Swede’s Landing to Woodhead Park.
These blooms aren’t uncommon when the weather gets warmer and oxygen levels within the water drop.
Until the blooms subside, health officials warn people and animals to avoid swimming, drinking or coming in contact with the water at all. Boiling or cooking with the water can increase your risk of exposure.
Toxins from the algae can build up in fish that swim in the affected waters. Fishermen should immediately wash their hands after touching a fish caught in this stretch of river.
If you intend to eat the fish, health officials say to fillet them, remove any skin or fat and immediately throw away any organs.
Symptoms of exposure include rashes, hives and vomiting. More severe symptoms affecting the liver and nervous system can develop from drinking the water.
The City of Boise has faced similar problems with cyanobacteria at Quinn's Pond and other parks in recent years. They've tried to keep the water temperature cooler and aerate more oxygen to help halt algae growth.
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