Is Clear Lake safe? Toxic algae status
Lake County, California. Harmful algal bloom (blue-green algae) reports from the California State Water Resources Control Board.
Data checked 24 October 2026. California data is updated daily.
233
bloom reports since 2016
11 of 11
years with a bloom reported (2016–2026)
74
advisories recommended: 57 Caution, 12 Warning, 5 Danger
Year by year
Each box shows bloom reports logged that year, coloured by the highest advisory recommended.
Reports at Clear Lake are most often logged in January, June and July.
Recent reports
| Date | Location | Result |
|---|---|---|
| 6 July 2026 | Buckingham Park | Caution |
| 6 July 2026 | north drive | Caution |
| 4 July 2026 | Horseshoe Cove | Bloom reported |
| 3 July 2026 | Soda Bay | Caution |
| 3 July 2026 | Monitor Point | Caution |
| 2 July 2026 | Soda Bay | Caution |
| 26 June 2026 | Multiple Locations (KEELING PARK,, Keys, maybe more) | Bloom reported |
| 7 September 2025 | Soda Bay | Caution |
| 4 September 2025 | Jones bay | Caution |
| 31 July 2025 | Jago Bay | Caution |
| 24 July 2025 | Wheeler Point, Kelseyville | Bloom reported |
| 26 June 2025 | Clear Lake Keys near Ketch Court | Caution |
What the results mean
Algae may be present. Stay away from scum and discoloured water, and keep pets and livestock from drinking it.
Toxins at higher levels. No swimming, and keep pets and children well away from the water.
High toxin levels. Stay out of the water and off the shoreline.
Dogs and toxic algae
Dogs face the greatest risk because they swallow water and lick algae off their fur. If a bloom has been reported, keep dogs out of the water and away from scum on the shore. If your dog swims in water that might have algae, rinse it with clean water straight away and call a vet if it seems unwell.
Common questions
Is Clear Lake safe to swim in?
The most recent entry in California's published data is from 6 July 2026: caution (Buckingham Park). Blooms have been recorded at Clear Lake in 11 different years, so treat green, scummy or discoloured water with caution. For current conditions, check the California HABs Portal map and posted signs.
When does Clear Lake get algae blooms?
In the state's records, reports are most often logged in January, June and July. Blooms are most likely in warm, calm weather, but they can appear at other times of year.
Source: California State Water Resources Control Board, official data. This page is independent and not affiliated with the State of California.