San Mateo County: lake and river algae advisories
17 waters in San Mateo County appear in the state's harmful algal bloom records. Waters whose latest record is an advisory come first.
| Water | Latest record |
|---|---|
| Alpine Pond | Caution advisory, last posted Aug 29, 2025. No all-clear recorded. |
| Foster City Marina Lagoon | Caution advisory, last posted Jun 26, 2026. No all-clear recorded. |
| Leslie Creek | Caution advisory, last posted Nov 8, 2024. No all-clear recorded. |
| Quarry Pond | Visual observation, last posted Aug 29, 2025. No all-clear recorded. |
| Redwood Creek | Caution advisory, last posted Aug 29, 2022. No all-clear recorded. |
| San Francisco Bay, Lower | Caution advisory, last posted Aug 25, 2022. No all-clear recorded. |
| San Mateo Marina Lagoon | Caution advisory, last posted Jun 26, 2026. No all-clear recorded. |
| Seal Slough | Caution advisory, last posted Jul 1, 2021. No all-clear recorded. |
| Windy Hill Open Space Preserve | Caution advisory, last posted Sep 9, 2024. No all-clear recorded. |
| Butano Creek | The state's latest record, from May 29, 2024, recommends no advisory. |
| Central Lake | The state's latest record, from Aug 30, 2022, recommends no advisory. |
| O'Neill Slough | The state's latest record, from Nov 13, 2017, recommends no advisory. |
| Pescadero Creek | The state's latest record, from Aug 30, 2022, recommends no advisory. |
| Pilarcitos Creek | The state's latest record, from Nov 27, 2018, recommends no advisory. |
| San Gregorio Creek | The state recorded an end date of Dec 31, 2022. |
| San Pedro Creek | The state's latest record, from Jun 6, 2022, recommends no advisory. |
| Sausal Pond | The state's latest record, from Aug 29, 2025, recommends no advisory. |