The algae is a type of bacteria commonly found in Colorado, but it can make humans and animals sick when it grows rapidly and results in a toxic "bloom." It's also been identified in Bear Creek Reservoir.
Personal paddle craft devices and rentals of paddleboats, canoes and kayaks from Rocky Mountain Paddleboard will still be allowed on the lake, but paddlers must limit contact with the water and rinse their boards immediately after contact, the city said.
Dogs and other animals should stay away from the water.
It wasn't known when Big Soda Lake, which is at the southwest side of Bear Creek Lake Park, will reopen to swimming.
The swim beach will remain open for shoreline use only.
Big Soda Lake is open daily from 8 a.m. to 8 p.m. through Labor Day.
The Colorado Department of Public Health and Environment recommends the following when you encounter an algae bloom:
- Stay out of the water.
- Don't drink the water.
- Keep pets and livestock away from the water.
- Avoid boating near or through algae blooms.
- Clean fish well with clean water and properly discard the guts.
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