Health advisory upgraded for Prineville Reservoir following toxic algae findings

PRINEVILLE, Ore. (KTVZ) -- The Oregon Health Authority (OHA) issued a recreational use health advisory today for Prineville Reservoir after laboratory results from recently collected water samples showed cyanotoxins above the recreational use value (RUV).

This health advisory upgrades a recreational use health precaution that has been in place for Prineville Reservoir since July 24 due to the presence of a visible harmful algae bloom. The elevated cyanotoxin levels detected in the water samples prompted the OHA's updated warning.

People should avoid swimming and other water activities that carry a high risk of swallowing water or inhaling water droplets in areas of the lake where blooms are present. This season, the bloom has primarily affected the portion of the reservoir to the east of Big Bend Island. However, caution should be taken in all portions of the reservoir.

Ingestion or inhalation of water is the exposure route of concern for cyanotoxins. The toxins are not absorbed through the skin. However, individuals with skin sensitivities may develop a puffy red rash.

OHA's RUVs are designed to protect the most vulnerable populations, such as children, who typically have higher activity levels and are more likely to swallow water while recreating.

Despite the advisory, OHA encourages visitors to Prineville Reservoir to enjoy activities such as fishing, camping, hiking, biking, picnicking, bird watching, canoeing and kayaking. Boating is considered safe as long as speeds do not create excessive water spray, which could lead to the risk of inhaling cyanotoxins.

Drinking water directly from areas of the lake affected by a bloom is especially dangerous. Boiling, filtering or treating water with camping-style filters cannot remove cyanotoxins. Individuals with questions about water available at nearby campgrounds or day use areas should contact campground management or the local health department.

Not all private treatment systems are effective at removing cyanotoxins. People who do not use a well or public water system and draw in-home water directly from an affected area are advised to use an alternative water source for drinking and cooking.

Children and pets face an increased risk of exposure due to their size, activity levels and higher likelihood of swallowing water.

For people, exposure to cyanotoxins can cause serious symptoms. These may include gastrointestinal issues similar to food poisoning, such as stomach cramps, diarrhea, nausea and vomiting. More severe symptoms like numbness, tingling, dizziness and shortness of breath may also occur and could require medical attention.

Dogs can become extremely ill and potentially die within minutes to hours of exposure. This can happen from drinking the water, licking their fur or eating toxins from floating mats or dried crusts along the shore. Symptoms in dogs can include difficulty walking, seizures, lethargy and loss of appetite. Veterinary treatment should be sought as quickly as possible if a dog exhibits these symptoms. OHA recommends keeping dogs on leashes and away from affected water and mat material to help reduce the chance of exposure.

Fish caught from areas with cyanobacteria blooms may pose unknown health risks. OHA recommends against eating fish from these areas. For those who choose to consume the fish, it is advised to remove fat, skin and organs, where toxins are more likely to accumulate, before cooking or freezing. Fillets should also be rinsed with clean water.

For health information or to report an illness, individuals can contact OHA at 971-673-0482 or visit OHA's Cyanobacteria (Harmful Algae) Blooms website.