Arastradero Lake: toxic algae advisories
Arastradero Lake, Santa Clara County. See all Santa Clara County waters.
What the state's records say
Danger advisory, last posted Apr 2, 2025. No all-clear recorded.
2 reported spots here have an advisory with no all-clear recorded.
Reporting is voluntary, so the state may not have recorded an end even if conditions changed. Check posted signs and the official map.
What this level asks: Toxins may be at levels that can seriously harm people and animals. Stay out of the water and keep children and pets away from the water and the shore.
Before you go, check the state's official algae page and any signs posted at the water.
Dogs at Arastradero Lake
The state has an advisory on file for Arastradero Lake (Danger advisory), last posted Apr 2, 2025, and no all-clear recorded. Keep your dog out of the water and away from scum on the shore until the state records an end.
Reported spots
The state records each report at a spot, such as a beach or a boat ramp. Each spot's latest deciding record:
| Spot | Status |
|---|---|
| Enid Pearson-Arastradero Reserve pumping station. | General awareness, last posted Apr 2, 2025. No all-clear recorded. |
| Pearson-Arastradero Preserve | Danger advisory, last posted Aug 23, 2024. No all-clear recorded. |
Advisory history
Every advisory record the state has published for Arastradero Lake, newest first. "None" is the state's record that no advisory was recommended on that date. "NA" records do not change a status.
| Date | Spot | State's level | Notes |
|---|---|---|---|
| Apr 2, 2025 | Enid Pearson-Arastradero Reserve pumping station. | General awareness | Suspected bloom, investigation ongoing |
| Aug 23, 2024 | Pearson-Arastradero Preserve | Danger |
Source
Advisory data: California State Water Resources Control Board, Freshwater Harmful Algal Bloom Program, via data.ca.gov (public domain). Advisories are recommendations; reporting is voluntary and incomplete. The state's data. An advisory ends only when the state records a later "None" (no advisory recommended) at the same spot, or an end date. A blank end date is unknown.