NewsCovering Colorado


Blue-green algae confirmed in Prospect Lake

Blue-green algae is a type of bacteria common in lakes throughout Colorado.
Posted at 5:19 PM, Jun 15, 2020
and last updated 2020-06-22 20:35:39-04

COLORADO SPRINGS — Test results from last week confirm that there is blue-green algae in Prospect Lake, according to the City of Colorado Springs.

The lake has been closed since June 15th and will remain closed until further notice.

The test that was taken on July 16th returned a mycrocystin level of 22 micrograms per liter. The acceptable recreational level for myrocystin, a toxin produced by cyanobacteria (also known as blue-green algae), is 4 micrograms per liter.

Test results will be published here.

The water has been treated three times already this year for blue-green algae, but will have its next treatment on Tuesday.

“Our region has again been experiencing hot, dry weather, creating conditions similar to what we experienced prior to the 2019 algae bloom in Prospect Lake,” said Erik Rodriguez, health, safety and environmental specialist with the Parks, Recreation and Cultural Services Department.

Prospect Lake was closed for 12 weeks in the late summer and early fall of 2019 due to blue-green algae.

Since that time, Parks’ staff has taken proactive measures, including the application of an enzyme-based, non-pesticide treatment that consumes the biomass at the bottom of the lake and helps oxygenate the water.

The first two treatments were applied May 26 and June 11. The next scheduled treatment is Tuesday. Additionally, more water will be added to the lake, which will increase the oxygen level and help dilute the toxin.

During the closure, the following activities are prohibited: swimming, bathing, paddle boarding, tubing, water skiing and non-motorized boating of any kind. No pets are allowed. The use of permitted motorized boats is encouraged as this activity can help aerate the water. Fishing areas will remain open, though anglers are urged to clean fish well and remove guts.