Mill Creek: toxic algae advisories
Mill Creek, San Bernardino County. See all San Bernardino County waters.
What the state's records say
General awareness, last posted Jul 1, 2026. 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: The state recorded an advisory of a type outside the Caution, Warning and Danger levels. Read the sign posted at the water.
Before you go, check the state's official algae page and any signs posted at the water.
Dogs at Mill Creek
The state has an advisory on file for Mill Creek (General awareness), last posted Jul 1, 2026, 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 |
|---|---|
| Mill Creek Random Olsen Site 370 | General awareness, last posted Jul 1, 2026. No all-clear recorded. |
| Hwy 38 and Mentone | The state's latest record, from Aug 16, 2023, recommends no advisory. |
| Mill Creek, Forest Falls | Algal mat alert sign, last posted Jul 7, 2022. No all-clear recorded. |
Advisory history
Every advisory record the state has published for Mill Creek, 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 |
|---|---|---|---|
| Jul 1, 2026 | Mill Creek Random Olsen Site 370 | General awareness | Advisory based on visual and toxins; Rec algal mat general awareness |
| Aug 28, 2025 | Mill Creek Random Olsen Site 370 | None | Advisory based on visual and toxins |
| Dec 5, 2024 | Mill Creek Random Olsen Site 370 | Algal mat alert sign | Advisory based on visual and toxins |
| Aug 26, 2024 | Mill Creek Random Olsen Site 370 | None | Advisory based on visual and toxins |
| Jun 28, 2024 | Mill Creek Random Olsen Site 370 | None | Advisory based on visual and toxins |
| Jun 28, 2024 | Mill Creek Random Olsen Site 370 | None | Advisory based on visual and toxins |
| Aug 24, 2023 | Mill Creek Random Olsen Site 370 | Algal mat general awareness sign | Advisory based on visual and toxins |
| Aug 16, 2023 | Hwy 38 and Mentone | None | Advisory based on visual and toxins |
| Aug 9, 2023 | Hwy 38 and Mentone | Algal mat general awareness sign | Suspected illness reported; Under investigation |
| Jun 20, 2023 | Mill Creek Random Olsen Site 370 | None | Advisory based on visual and toxins |
| May 24, 2023 | Mill Creek Random Olsen Site 370 | None | Bottom/benthic bloom observed |
| Jul 7, 2022 | Mill Creek, Forest Falls | Algal mat alert sign | Advisory based on visual and toxins |
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.