Prospect Lake in Memorial Park is now open following a mandatory closure and two consecutive negative tests for an elevated concentration of blue-green algae.
The popular lake near downtown Colorado Springs closed on Wednesday, July 24 due to a positive test confirming the presence of mycrocystin toxin, which is produced by cyanobacteria, also known as blue-green algae.
“We would like to thank the public for their understanding and patience as we worked to address the algae blooms in Prospect Lake,” said Erik Rodriguez, senior environmental, health and safety specialist for Parks, Recreation and Cultural Services (PRCS). “The health and safety of our community is our top priority and with the extra chemical-free treatments, we are pleased to announce that the lake is now open again for everyone to enjoy.”
The following activities are now permitted at Prospect Lake: swimming, bathing, paddle boarding, tubing, water skiing and non-motorized and motorized boating.
Due to warmer temperatures, algae blooms are still possible throughout the summer months. Visitors are encouraged to use caution by not drinking the water, keeping children and pets out of the water and avoiding any contact with algae that may be present. Fishing is permitted but anglers need to rinse fish with clean water and properly dispose of organs when processing. Boaters must also avoid any visible algae contact.
PRCS staff will continue to monitor and perform weekly testing to ensure safe, recreational water quality levels set by the CDPHE and the EPA.
BLUE-GREEN ALGAE BACKGROUND
What is harmful algae?
Blue-green algae are a type of bacteria common in lakes throughout Colorado. When conditions are right, blue-green algae multiplies quickly. Those conditions include sustained hot weather, stagnant water, and polluted stormwater runoff.
These conditions result in too much nitrogen, potassium and phosphorus in the water. This causes the harmful bacteria to grow faster than the ecosystem can handle. The increased bacteria harm water quality, decrease the amount of oxygen available to animals living in the water, and can produce a toxin that is harmful to humans and pets.
Blue-green algae are self-limiting, naturally-occurring bacteria, which means it eventually phases itself out of bodies of water.
Blue-green algae can make the water look green, turquoise, gold, or red. It can also look like thick pea soup or spilled paint on the water’s surface and be made up of small specks or blobs floating at or just below the water’s surface. Please be vigilant for these signs in all warm lakes prior to letting anyone including pets enter the water.
The Colorado Department of Public Health and Environment (CDPHE) offers additional information about blue-green algae on its website.