New York
Toxic algae in Otsego County lakes
11 lakes and waterways in Otsego County have harmful algal bloom reports in New York's official data. The most recent entry is for Otsego Lake: Otsego Lake was on New York's harmful algal bloom list from 6 August 2025 to 18 September 2025, with confirmed bloom status (4 reports). Otsego Lake, Gilbert Lake and Canadarago Lake 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.
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.
- Allen Lake 2025
- Allens Pond 2016
- Arnold Lake 2022
- Buck Horn Lake 2022
- Clarke Pond 2024
- Shadow Brook 2022
- Unadilla River 2024
- Wilber Lake 2020
Source: New York State Department of Environmental Conservation (DEC), official data, checked 24 October 2026. For today's conditions see the NYHABS map. No report doesn't mean a lake is safe: most water is only tested occasionally.