Toxic algae in Marin County, California
18 lakes and waterways have harmful algal bloom reports in California's official data.
Lakes with bloom history
| Lake | Years with reports | Most recent |
|---|---|---|
| Richardson Bay | 3 | 2023 |
| Marin Civic Center Lagoon | 3 | 2025 |
| Scottsdale Pond | 2 | 2025 |
| Stafford Lake | 2 | 2026 |
| Tomales Bay | 2 | 2024 |
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)
- Corte Madera Creek (2025)
- Drakes Bay (2023)
- Lagunitas Creek (2022)
- Miller Creek (2025)
- Muddy Hollow Creek (2026)
- Nicasio Reservoir (2021)
- Novato Creek (2024)
- Pine Gulch Creek (2026)
- Rush Creek Marsh Wildlife Area (2026)
- San Geronimo Creek (2023)
- San Rafael Canal (2023)
- San Rafael Creek (2019)
Source: California State Water Resources Control Board, official data. For current conditions see the California HABs Portal map.