Main content
Complete
Department:
Parks, Recreation and Cultural Services
Parks, Recreation, and Cultural Services
March 6, 2023
  • Community Meeting
  • Survey will be open March 6- 30
March 9, 2023
  • Presentation to Parks, Recreation and Cultural Services Advisory Board
March 27, 2023
  • Presentation to City Council during work session
    Note: There is no public comment during work sessions.
April 2023
  • Final summary of the design alternatives will be presented to City Leadership for a decision on which alternative to move forward with for installation.
May 2023
  • Bid process and selection of a contractor
October 28, 2024
  • Construction start date
December 2025
  • Project completion

Overview

The Prospect Lake Aeration Project at Memorial Park is complete, delivering long-term improvements to water quality and overall lake health. The new system increases oxygen levels throughout the lake, reducing harmful algae growth and supporting a healthier aquatic ecosystem. These improvements enhance year-round recreational opportunities for the community. 

Current status

Aeration Design 1 Selected for Installation – Motorized Boating to Continue with this Design

With approximately $450,000 from the American Rescue Plan Act (ARPA), the City worked with a consultant to design and install a permanent system to address lake health issues.  The main objective of the system is to implement a continuous aeration system and an as-needed injection system capable of distributing liquid treatment to the lake to combat blue green algae blooms and fish kills.  Design 1 has been selected which consists of one (1) compressor with eight (8) double-disk membrane diffusers.  The aeration lines and diffusers are situated on the lakebed and are placed to target the deepest parts of the lake while maintaining full lake coverage.  Injection lines are coupled with the aeration lines to allow for the dispersal of enzymes into the water body on an as-needed basis.  The design includes a structure, built on the east side of the lake, to house the compressors and injection system tank. 

Design 1 will turn over the water in the lake at a 0.45 rate per day which results in the lake turning over about every two (2) days.  This level of effort will reduce the excess nutrient content within the lake.  Due to its focus on treating the deepest parts of the lake, Design 1 supports continued motorized activity on Prospect Lake.

The City released a Request for Proposal (RFP) for construction of the Prospect Lake Aeration System on March 4, 2024.  After the RFP closed on April 5, 2024, the City will selected a contractor.

About

Prospect Lake

Prospect Lake is located in the southeast corner of Memorial Park.  The land where the lake is located was deeded by General William Jackson Palmer in 1890. It served as the reservoir to irrigate Evergreen Cemetery until a non-potable irrigation system was installed in 1950. Since that time, Prospect Lake has served as a recreational amenity for both residents and visitors alike. 

Lake aeration basics

Lake aeration is a process of introducing oxygen into a body of water to improve its water quality. The aerator works by forcing air bubbles through the lake water. The oxygen in the air bubbles then diffuses into the lake, which helps reduce the levels of pollutants in the water and increase the number of beneficial bacteria in the lake among other water quality improvements. Both design alternatives utilize aeration to improve water quality with Design 2 incorporating ultrasonic algae control units that float on the surface of the water to further inhibit algae growth.