Detroit Lake under another algae health alert

The Oregon Health Authority issued another recreational health advisory Thursday for Detroit Lake, located 46 miles southeast of Salem. The lake spans both Linn and Marion counties.

Water monitoring has confirmed the presence of cyanotoxins at levels above Oregon Health Authority recreational guideline values. Cyanotoxins can be produced by colonies of cyanobacteria commonly referred to as harmful algae blooms. At measured levels, cyanotoxins can be harmful to humans and animals.

Oregon health officials advise recreational visitors to always be alert to signs of cyanobacteria (harmful algae) and avoid areas with visible scum that looks foamy, thick like paint, pea-green, blue-green or brownish-red, or where small bright-green clumps are floating in the water.

According to new protocol announced Monday, a recreational use health advisory at Detroit Lake can be lifted when test results show cyanotoxin levels in water samples taken from the lake on three consecutive days are below recreational guideline levels, and that City of Salem visual assessments near sampling locations find the algae bloom has subsided.

People should avoid swimming and high-speed water activities, such as water skiing or power boating, in areas where blooms are identified. Although toxins are not absorbed through the skin, people who have skin sensitivities may experience a puffy red rash at the affected area.

People who draw in-home water directly from the affected area are advised to use an alternative water source because private treatment systems are not proven effective for removing cyanotoxins. However, public drinking water systems can reduce these toxins through proper filtration, disinfection and other treatment. The Santiam River downstream of Detroit Lake is the source of drinking water for several cities, including the City of Salem. The City of Salem’s drinking water advisory is still in place for vulnerable populations. For more information about the city’s water advisory, visit www.cityofsalem.net.

Exposure to cyanotoxins can produce a variety of symptoms including numbness, tingling and dizziness that can lead to difficulty breathing or heart problems and require immediate medical attention. Symptoms of skin irritation, weakness, diarrhea, nausea, cramps and fainting should also receive medical attention if they persist or worsen. Children and pets are at increased risk for exposure because of their size and level of activity. People who bring their pets to Detroit Lake for recreation activities should take special precautions to keep them from drinking from or swimming in the lake.

Drinking water directly from Detroit Lake at this time is especially dangerous. OHA Public Health Division officials advise campers and other recreational visitors that cyanotoxins cannot be removed by boiling, filtering or treating water with camping-style filters. If community members have questions about water available at nearby campgrounds, they should contact campground management.

Oregon health officials recommend that those who choose to eat fish from waters where cyanobacterial blooms are present remove all fat, skin and organs before cooking, as cyanotoxins are more likely to collect in these tissues. Fillets should also be rinsed with clean water.

Public health officials also advise people to not eat freshwater clams or mussels from Detroit Lake and that Oregon Department of Fish and Wildlife regulations do not allow the harvest of these shellfish from freshwater sources. Crayfish muscle can be eaten, but internal organs and liquid fat should be discarded.

With proper precautions to avoid activities during which water can be ingested, people are encouraged to visit Detroit Lake and enjoy activities such as canoeing, fishing, camping, hiking, biking, picnicking, and bird watching. Boating is safe as long as speeds do not create excessive water spray. Although inhalation risk is much lower than ingestion, it can present a risk.

For health information or to report an illness, contact OHA at 971-673-0400. For campground or lake information, call the local management agency.

OHA maintains an updated list of all health advisories on its website. To learn if an advisory has been issued or lifted for a specific water body, visit the Harmful Algae Blooms website at http://www.healthoregon.org/hab and select “algae bloom advisories,” or call the Oregon Public Health Division toll-free information line at 877-290-6767.