06/17/2025
Precautionary harmful algae advisories have been issued by Oregon Health Authority for Lost Creek Lake in Jackson County (where a dog was reported to have died), Prineville Reservoir in Crook County and Devil's Lake in Lincoln County. (Precautionary status means a bloom has been sighted and water sampling is unavailable within 1 business day due to limited resources.)
UPDATE: Since this post, additional warnings have been issued for: Lake Billy Chinook in Jefferson County (cyanotoxins are above recreational use values for human exposure which means they are too high for animal exposure as well) and Fern Ridge Reservoir in Lane County. The decision to issue the advisory for Fern Ridge is based on a report of a toxigenic bloom from a partner agency. Results of testing in the days to come will either confirm the advisory or allow it to be lifted.
Additionally, an advisory was issued by Washington for the Columbia River shoreline at Cottonwood Beach in Washougal. This advisory is for benthic algae mats, which are often attached to the bottom of waterways in mats, blobs or spires, or detached and floating in clumps. They can occur anywhere in a fast or slow-moving water body, do not affect water clarity, and can feel slimy, gelatinous or slippery.
Read more about benthic algae mats and harmful algae blooms in the PNW: https://www.aaha.org/trends-magazine/publications/how-to-keep-pets-safe-from-harmful-algal-blooms/
When in doubt, stay out!
