Prospect Lake aeration system planned to prevent poisonous algae blooms

Plans for a new aeration system in Prospect Lake that would prevent poisonous blue-green algae may be installed in the new year after facing delays. 

The aeration system has been controversial because depending on the design it could prohibit motorboats from using the lake. Advocates fighting to preserve motorboating access say options for boating around Colorado Springs are limited and the city committed in the 1970s to keep Prospect Lake open to boats until an alternative arose. 

The restriction on boating will likely depend on the type of aeration system the city installs. 

Parks staff expected to receive designs for a new aeration system in the fall, but it hasn't gotten them yet because the contractor tasked with developing the plans had three people cycle through a project manager position, said Kim King, the city's recreation and administration manager.

The city still expects to receive designs for an aeration system, including options that could allow for boating, King said. She would like to have the system installed ahead of the 2023 summer boating season, she said.

"This level of oxygenation is just going to be an overall fantastic addition for overall water quality," King said. 

Prospect Lake had a fairly good water-quality season in 2022, only closing once for an E. coli test, she said. But in previous summers, the lake closed for long stretches because of the algae that has killed fish. The algae has been found in numerous reservoirs across Colorado and thrives in warm, calm water, according to the state health department. 

Parks staff prevented algae in 2022 by adding water later in the season and using enzyme treatments. But enzyme treatments will not replace the need for a permanent aeration system, she said.

The city said previously it had set aside $459,036 in American Rescue Plan Act funding for the aeration project. However, staff does not have cost estimates for the project because the designs have not been finished.

To stay within federal guidelines, the city needs to be under contract for construction by 2024 and finish it by 2026, King said.

The city expects to have public meetings and post updates on its website when details about the new aeration system come available.