Trotter and Associates, Inc. worked alongside Joseph J. Henderson & Son, Inc, and DuPage County Public Works to complete the construction and startup of Phase I of the Nordic WWTP Rehabilitation Project. 

The team has completed demolishing the County’s existing package plant, which includes two Aeration Basins, two Tertiary Clarifiers, and an Aerobic Digester. These were in addition to other structures that have been previously demolished, including the Blower Building, Administration Building, Sand Filter Building, Compressor Building, and UV Disinfection Channel.

The 0.5 MGD plant was kept in service throughout the project by utilizing temporary structures, equipment, process piping, and electrical service. Other challenges included the site’s small size, as the area is merely 0.65 acres inside the fence. In addition, the plant sits on a 100-year floodplain and is bordered by critical wetlands to the south and regulatory wetlands to the north. These important factors required construction activity to be finely orchestrated to construct and maintain the necessary temporary processes within the fence, without affecting the floodplain or surrounding wetlands.

The new processes that were constructed and put into service include one of two fine-bubble Aeration Basins, four rotary lobe blowers, both Tertiary Clarifiers, the RAS/WAS Pumping Station with three submersible pumps, two in-line UV disinfection vessels, and the aerated Sludge Storage Tank that was converted from the County’s existing Spiragester. In addition, all necessary electrical and control equipment has been completed for Phase I allowing the plant to operate remotely, with minimal on-site operation procedures required.

DuPage County Public Works has completed its first composite sample on the new plant with fantastic operational results. TAI is proud to have been so closely involved in the design and construction of Phase I and is looking forward to completing Phase II which will include:

• Replacement of the Raw Influent Pumps and rehabilitation of the existing Headworks Structure.
• Construction of the second Aeration Basin.
• Installation of the new Sludge Loadout Pumping System.