Wet Weather Treatment Facility and Reservoir, Lemont Water Reclamation Plant, Contract 10-716-3P

• Location: Lemont, IL
• Contract Value: $29,663,517
• Owner: Metropolitan Water Reclamation District of Greater Chicago (MWRD)
• Engineer: CH2M Hill
• Delivery Method: Design-Bid-Build
• Award: LCCA Award for Project Excellence (APEX)

A multi-phased project included the installation of a 5MG wet weather reservoir for storage of the initial excess flow, and installation of a wet weather treatment facility which provides primary treatment and disinfection for flows above treatment and storage capacity to greatly relieve wastewater discharges into the adjacent sanitary and ship canal.

The project includes a new pump station, a diversion structure for emergency high level overflow, separator and disinfection, and yard piping and tie-ins to an existing electrical and controls distribution system. Additionally, a significant component of the project is the construction of a diversion structure for emergency high-level overflow. The wet weather reservoir and wet well is a large in-ground concrete structure that measures 65.5x50x9m deep. The concrete walls are up to 1m thick and the base is 1.2m thick. It is expected to be solid, leak-proof, and capable of handling overflow from the biggest storms.