California
Toxic algae in El Dorado County lakes
27 lakes and waterways in El Dorado County have harmful algal bloom reports in California's official data. The most recent entry is for Trout Creek: A bloom was reported at Trout Creek on 19 October 2026 at Lake Tahoe Community College. Lake Tahoe, Upper Truckee River and Tahoe Keys Lagoon and 3 more 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.
- Trout Creek Bloom reported
- Meeks Creek Bloom reported
- Sly Park Creek Bloom reported
- Lake Tahoe Bloom reported
- Upper Truckee River Bloom reported
- Taylor Creek Awareness sign
- Tahoe Keys Lagoon Bloom reported
- General Creek Awareness sign
- Lake Baron Bloom reported
- Big Meadow Creek Bloom reported
- Silver Fork American River Bloom reported
- Star Lake Bloom reported
- Round Lake Bloom reported
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.
- American River South Fork 2020
- Big Silver Creek 2025
- Canyon Lake 2019
- Cascade Creek 2022
- Cat Creek 2024
- Dardanelles Lake 2019
- Grass Lake Creek 2024
- Heavenly Valley Creek 2025
- Ice House Reservoir 2023
- South Lake Tahoe 2026
- Taboose Creek 2022
- Tallac Creek 2023
- Taylor Creek Meadow Marsh 2023
- Wrights Lake 2018
Source: California State Water Resources Control Board, official data, checked 24 October 2026. For today's conditions see the California HABs Portal map. No report doesn't mean a lake is safe: most water is only tested occasionally.