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Recreational use health advisory for Dorena Reservoir lifted June 22


Recreational use health advisory for Dorena Reservoir lifted June 22

Reduced cyanobacteria, cyanotoxin levels confirmed

The Oregon Health Authority has lifted the recreational use health advisory issued June 13 for Dorena Reservoir, located six miles east of Cottage Grove in Lane County, due to the presence of a cyanobacteria (harmful algae) bloom.

Water monitoring has confirmed that the level of cyanotoxins (harmful algae toxins) in the reservoir are below recreational guideline values for human exposure. However, OHA officials advise recreational visitors to always be alert to signs of a cyanobacteria (harmful algae) blooms in all Oregon waters, because blooms can develop and disappear throughout the season. Only a fraction of the many lakes and waterways in Oregon are monitored for cyanobacteria by state, federal and local agencies, therefore, you are your own best advocate when it comes to keeping you and your family safe while recreating.

People and especially small children and pets should avoid recreating in areas where the water is foamy, scummy, thick like paint, pea-green, blue-green or brownish red in color, if a thick mat of blue-green algae is visible in the water, or bright green cells are suspended in the water column. If you observe these signs in the water you are encouraged to avoid activities that cause you to swallow water or inhale droplets, such as swimming or high-speed water activities.

For health information or to report an illness, contact the Oregon Health Authority (OHA) at 971-673-0440.

For information about recreational advisories issued or lifted for the season, contact the Oregon Public Health toll-free information line at 1-877-290-6767 or visit the Harmful Algae Blooms website at and select “Algae Bloom Advisories.”

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 Media contact

Delia Hernández

OHA External Relations


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