Toxic algae in Santa Clara County, California
13 lakes and waterways have harmful algal bloom reports in California's official data.
Lakes with bloom history
| Lake | Years with reports | Most recent |
|---|---|---|
| Almaden Reservoir | 5 | 2021 |
| Lake Cunningham | 3 | 2018 |
| Shoreline Lake | 3 | 2026 |
| Arastradero Lake | 2 | 2025 |
| Lake Almaden | 2 | 2024 |
| Upper Lake | 2 | 2025 |
Other waterbodies with a report
These have one or two reports in a single year, so there isn't enough history for a page of their own yet.
- Arroyo Hondo Creek (2026)
- Boronda Lake (2024)
- Calaveras Creek (2018)
- Llagas Creek (2026)
- Stevens Creek Reservoir (2025)
- Swanson Creek (2023)
- Uvas Creek (2026)
Source: California State Water Resources Control Board, official data. For current conditions see the California HABs Portal map.