The South-Central Public Health District (SCPHD) and the Idaho Department of Environmental Quality (DEQ) are issuing a public health advisory today for Mormon Reservoir. Results from recent DEQ water testing show the concentration of microcystins (a type of toxin produced by cyanobacteria) in the reservoir are now at unhealthy levels because of a current cyanobacteria harmful algal bloom (HAB). This is the second health advisory issued for a reservoir in south-central Idaho. The first was issued on July 8th for Salmon Falls Creek Reservoir, and is ongoing.

The public is advised to take the following steps to protect their health in both reservoirs:

Avoid exposure to water in reservoirs under a HAB health advisory. Make sure children, pets, and livestock are not exposed to the water.

Do not drink water with a HAB advisory. Boiling and disinfecting DO NOT remove toxins from water.

Do not allow pets to eat dried algae

If fishing in HAB water, remove all fat, skin, and organs before cooking. Toxins are more likely to collect in those tissues. Wash hands after handling.

“These toxins aren’t safe for humans or animals,” said Craig Paul, SCPHD Environmental Health Division Director.  “Eye, ear, and skin irritations are most common in people who touch the water but it can be much more serious for animals.”

HABs are not unusual in warm summer months and typically shrink quickly as the water temperature drops in mid to late fall. SCPHD will issue another press release when DEQ tests show Mormon Reservoir and Salmon Falls Creek Reservoir are at safe cyanotoxin levels again.

“You can help by reporting suspicious looking water to DEQ by phone, email, or with the bloomWatch app,” said Brian Reese, DEQ Water Quality Standards Analyst.

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