KANSAS CITY, MO, Sept. 18, 2008 -- Burns & McDonnell announced that it has completed a water aeration system replacement and sedimentation removal project at the 60-acre Berlin Reservoir and 1-acre pond at Kansas City International Airport. The project was constructed at a cost of $330,000. Burns & McDonnell has been assisting the Kansas City Aviation Department (KCAD) in management of stormwater water quality issues since 1998. This specific project is the latest initiative by KCAD to reduce energy consumption and further protect our environment.
The design of a diffused aeration system provides a significant energy savings. The new innovative air entrainment system accelerates natural processes in the respective impoundments by turning over all the water every 36 hours.
The previous system used an antiquated system of stirrers to keep the water aerated. The new system significantly increases the dissolved oxygen content in the water through an air entrainment process that sends compressed air through weighted hoses to diffusers on the lake bottom. The air bubbles then agitate the water in a much more efficient manner than similar agitation processes utilizing mechanical rotors in treatment lagoons. The increased volume of dissolved oxygen speeds up decomposition of organic material and recycles nutrients, which increases the phytoplankton population and uses carbon dioxide from the atmosphere.
"Increasing sediment and organic loads in impoundments like the Berlin Reservoir and KCI pond is threatening water supply and quality nationwide," said Dennis Haag of Burns & McDonnell, lead designer of the aeration systems. "We are using several new methods to restore lakes and ponds and manage sediment and organic loads that are alternatives to building new dams or conventional dredging. Essentially, we are unleashing natural forces to speed up the decomposition process that may avoid the cost and disturbance of creating sediment detention basins."
There is expected to be a 75 percent annual energy savings compared to the existing systems, which will pay for the new system in approximately five years. For aesthetics, floating fountains were installed on five floating aeration platforms in Berlin Reservoir.
Another portion of the project included hydraulic dredging of accumulated sediments in a 1-acre pond. A hydraulic "mini-dredge" was used to pull sediment from the bottom of the pond and collect the spoils in large geotextile filter (spoil) bags. A polymer was injected into the discharge pipe during dredging. The spoil bags and blended polymer rapidly concentrated and de-watered the sediment in a short period of time and avoided the cost and disturbance of creating sediment detention basins. The new system has reduced the volume and cost of disposal of dredged sediments.
Burns & McDonnell provides engineering, architecture, construction, environmental and consulting services to clients throughout North America and abroad.
###
