Health officials have issued a lakewide warning advisory for Utah Lake after finding harmful algal blooms, or HABs, with toxicity levels above the safe recreational threshold.

The warning advisory, issued by the Utah County Health Department on Friday, states that samples taken from the open lake water on July 13 show toxigenic cyanobacteria cell counts at 1.8 million cells per milliliter, significantly above the Utah Division of Water Quality and Utah Department of Health’s recommended warning advisory threshold of 100,000 cells per mL.

The lakewide warning advisory comes just days after health officials issued a warning advisory for American Fork Beach and kept advisories in place at Lincoln Beach and Provo Bay due to HABs above the safe recreational threshold.

On July 7, a DWQ toxic algae monitoring team visited Utah Lake and observed algal blooms “at American Fork Beach, American Fork Marina near the boat ramp, Saratoga Springs Marina boat ramp and picnic area, Lindon Beach, south of Lindon Marina, and the beach north of the Lindon Marina,” the DWQ wrote in a blog post.

Marinas will remain open for boat traffic to access Utah Lake, but water recreation within the Provo Bay, Lincoln Beach and the American Fork Marina “should be avoided,” according to the county health department.

HABS, which the DEQ notes develop “when naturally occurring cyanobacteria in the water multiply very quickly to form green or blue-green water, scum, or mats” and “can produce potent cyanotoxins that pose serious health risks to humans, pets, and livestock,” have been an issue at Utah Lake and other water bodies for years.

Also on Friday, the Southeast Health Department issued a danger advisory for the Scofield Reservoir, which “indicates a potential for acute poisoning and long-term illness from harmful algal bloom exposure,” and advised visitors to not swim, water-ski or boat in the reservoir.

On June 1, health officials downgraded a danger advisory at the North Fork Virgin River in southern Utah to a warning advisory “based on May 2021 sampling results,” but still advised visitors “to avoid submerging their heads in the water.”

Symptoms of human exposure to HABs include rashes, hives or blisters from skin contact, a runny nose, sore throat and asthma, while symptoms of animal exposure include weakness, staggering, difficulty breathing, vomiting and convulsions.

To stay safe, health and water officials recommend avoiding swallowing water when swimming, washing hands with clean water before preparing or eating food, cleaning fish well and discarding of guts, keeping animals away from the water and recognizing the signs of algal blooms.

For concerns about possible human or animal exposure, call the Utah Poison Control Center at (800) 222-1222, or report a bloom by calling the 24-hour Utah Department of Environmental Quality incident line at (801) 536-4123.

Connor Richards covers government, the environment and south Utah County for the Daily Herald. He can be reached at and 801-344-2599.

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