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Current Cyanobacteria Advisories

The table below is continually updated with the most current information on recreational use health advisories issued and lifted throughout the season for monitored and sampled water bodies.

Remember: Only a fraction of all water bodies in Oregon are visually monitored or sampled due to limited physical and monetary resources. A water body with no recreational health advisory is not an indication that a bloom is not present. You are your own best advocate when ensuring your safety, and that of your family and pets. Be aware and "when in doubt, stay out."

advisory= Advisory in effect  lifted= Advisory has been lifted  permanent= Permanent advisory




Waterbody 
Status 
Link 
County 
Toxin  Data (ppb)

Lake Ewauna
advisoryAdvisory in effect
September 22, 2023
Klamath
Microcystin
       8 
Willow Creek Reservoir
advisoryAdvisory in effect
September 19, 2023
Morrow
Microcystin
     46 
Hells Canyon Reservoir 
advisoryAdvisory in effect 
August 3, 2023

Wallowa and Baker (issued by State of Idaho)
Microcystin 
    >50
Brownlee Reservoir
advisoryAdvisory in effect 
August 3, 2023
Baker (issued by State of Idaho)
Microcystin
    >50

Agency Lake
advisory Advisory in effect
July 25, 2023Klamath
Microcystin
     16
Upper Klamath Lake
advisory Advisory in effect
July 25, 2023Klamath
Microcystin
     41

Willamette River in Portland
lifted  Advisory has been lifted
September 28, 2023
Multnomah
Microcystin

Aarons Lake
lifted  Advisory has been lifted
September 14, 2023Columbia
Microcystin


Pete's Slough & Sturgeon Lake
lifted  Advisory has been lifted
August 25, 2023Columbia & Multnomah
Microcystin

Cullaby Lake
lifted  Advisory has been lifted
August 21, 2023Clatsop
Cyanobacteria
Galesville Reservoir

lifted  Advisory has been lifted
June 30, 2023
Douglas
Cyanobacteria
South Umpqua River and mainstream Umpqua River permanentPermanent Recreational Use Advisory Posted SignDouglas






Douglas County Permanent Recreational Use Advisory: South Umpqua River and mainstem Umpqua River

The advisory covers the South Umpqua River from Canyonville downstream to the confluence with the mainstem Umpqua River, and the mainstem Umpqua River downstream past Elkton to Sawyers Rapids. Pools in the bedrock along the rivers edge are known to develop cyanobacteria (blue-green algae) blooms that can be harmful to pets and people if accidental ingestion occurs. Signs have been posted at several access areas along the river.