California
Toxic algae in Santa Cruz County lakes
13 lakes and waterways in Santa Cruz County have harmful algal bloom reports in California's official data. The most recent entry is for Corcoran Lagoon: There are no bloom reports for Corcoran Lagoon in the last 30 days of California's data. The most recent was a bloom report on 28 May 2025 at Santa Cruz. Pinto Lake 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.
- College Lake 2025
- Drew Lake 2025
- Kelley Lake 2016
- Kelly Lake 2025
- Moran Lagoon 2025
- Pine Lake 2017
- San Lorenzo River Estuary 2015
- Santa Cruz Harbor 2020
- Schwan Lake 2025
- Tynan Lake 2020
- Valencia Creek 2024
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.