GRANBY, Colo. (KDVR) – Officials closed the Willow Creek Reservoir for water activities on Saturday, warning that there is a potential toxic blue-green algae bloom.
Willow Creek Reservoir is west of Highway 34 between Granby and Grand Lake and is normally open to non-motorized recreation only.
Forest officials say they are working in close coordination with Grand County, Colorado Parks and Wildlife, Bureau of Reclamation, Northern Water, and others to ensure the appropriate steps are taken to keep the public safe and assess when the area can reopen.
Officials say algae are an important part of aquatic food webs, but some types of blue-green algae can produce toxins that may cause negative health impacts for humans and pets at elevated concentrations.
Currently there is no method to remove toxins from lakes. The Colorado Department of Public Health and Environment (CDPHE) recommends the following:
- Keep kids out
- No pets in water
- Do not drink water
- Avoid contact with algae
The Colorado Department of Public Health describes blue-green algae (also known as cyanobacteria) as a photosynthetic bacterium that is common and natural to waters found in all states, including Colorado.
When water temperatures are warmer and extra nutrients are present most commonly in sunny yet still waters, these algae can multiply to form algal blooms. Some of the algae can start producing toxic compounds called cyanotoxins.