Florida
Toxic algae in Pinellas County lakes
21 lakes and waterways in Pinellas County have harmful algal bloom reports in Florida's official data. The most recent entry is for Harbor Lake: Florida's most recent sample from Harbor Lake, on 9 December 2025 at Harbor Lake - off Norwegian Dr, found no visible bloom and no microcystin toxin was detected. Harbor Isle has 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.
- Alligator Lake 2025
- Bear Creek 2021
- Boca Ciega Bay 2022
- Broker Creek 2025
- Eagle Lake 2025
- Lake Disston 2022
- Lake Maggiore 2025
- Lake Seminole North 2019
- Lake Seminole South 2019
- Little Salt Lake 2022
- Little Salt Lake Ne 2021
- Round Lake 2021
- Safety Harbor 2019
- Woody Ibis Park Lake 2022
Source: Florida Department of Environmental Protection (DEP), official data, checked 24 October 2026. For today's conditions see the DEP Algal Bloom Dashboard. No report doesn't mean a lake is safe: most water is only tested occasionally.