Algae and Vegetation Control in Denver LakeAquatic Weed and Algae Control Case Study

Location and Acreage:Denver, CO | 23.5-Acres

Project Timeframe: 2016

Project Manager:Chuck Rodosevich, Aquatic Specialist

Site Description:This lake is located in Denver, CO. This park contains the Denver Zoo and the Denver Museum of Science and Nature. The 23.5-acre lake has a history of recurring filamentous algae blooms, often so notable they get attention of the local news and media publications. SOLitude Lake Management was hired by the City of Denver in late summer of 2016 to help create a treatment plan focusing on algae control and nutrient remediation.

Poor Water Quality and Toxic Algae Blooms    Restored Water Quality of A Park Lake

Scope of Work:Filamentous algae treatments, water quality testing, Phoslock applications

Project Description:In August 2016, the restoration program on this property started with filamentous algae and vegetation treatments. Due to concerns with reduction in dissolved oxygen from the significant decaying algae and vegetation and the high-profile location, the algae treatment program was structured to occur in three separate applications.

The first treatment occurred in mid-August. Approximately seven days later, another application was performed. Significant control was achieved after these two applications so only a minor follow-up application in early September was completed for the third treatment. The project included a Phoslock application to be done after algae treatments to bind additional free reactive phosphorus released from the treatments.

The project concluded in the end of September. Water quality tests collected demonstrated that thee Total Phosphorus was reduced by almost 75 % and the Free Reactive Phosphorus was reduced by almost 85% after Phoslock application. Denver City Parks representatives were very pleased with the results and relayed that they would like to complete additional applications to maintain the current improvements seen at this lake as well as other resources within other City of Denver parks.