Oregon
Toxic algae in Baker County lakes
4 lakes and waterways in Baker County have harmful algal bloom reports in Oregon's official data. The most recent entry is for Thief Valley Reservoir: Oregon issued a health advisory for Thief Valley Reservoir in 2025, listed on 23 December 2025. Brownlee Reservoir and Hells Canyon Reservoir have had blooms in three or more years.
Lakes with bloom history
Newest report first. Each lake has its own page with the full history and what the results mean.
Other waterbodies with a report
These have one or two reports in a single year, which isn't enough history for a page of their own yet.
- Unity Reservoir 2025
Source: Oregon Health Authority (OHA), official data, checked 24 October 2026. For today's conditions see the OHA current advisories page. No report doesn't mean a lake is safe: most water is only tested occasionally.