Award of Merit, Water/Environment: Kokomo Excess Flow Treatment Facility (PEFTF)

Kokomo Excess Flow Treatment Facility (PEFTF)

Kokomo, Ind.

Merit Award

Presented by Lochmueller Group

Owner: The city of Kokomo, Ind.

Principal/Civil Design Company: Lochmueller Group Inc.

General contractor: Kokosing Industrial

Structural Engineer: VPS architecture

MEP Engineer: Sims/Durkin Associates Engineering

Through proactive planning, strategic design adjustments and close collaboration, the City of Kokomo Peak Excess Flow Treatment Facility (PEFTF) team completed the project two months ahead of schedule and $558,037 under budget.

As part of the next phase of the city’s Long-Term Combined Sewer Overflow Control Plan and to meet Indiana Department of Environmental Management requirements, the PEFTF expanded the wet weather treatment capacity at the Kokomo Wastewater Treatment Plant (WTP) along Wildcat Creek to 117 million gallons per day.

The facility features a chemically enhanced high rate clarification (CEHRC) system that uses hydrodynamic separation and chemical disinfection technology. This offers a more streamlined, cost-effective and low-maintenance solution compared to traditional systems and relies on minimal mechanical components and low-flow pumps for operation.

Initial plans were to have two separate wet weather treatment facilities, but during planning, the team identified an opportunity to consolidate both into a single treatment facility at the existing plant. This decision simplified design and operations; reduced long-term construction and maintenance costs; and eliminated the need for chemical product deliveries through residential neighborhoods.

However, the project also faced environmental and structural challenges. Crews encountered polychlorinated biphenyl (PCB)-affected soils that required careful remediation and complex underground utility networks, which required specialized excavation and shoring methods to maintain the integrity of adjacent infrastructure.

One of the team’s biggest challenges was integrating the new system with an existing, underperforming PEFTF. To do this, the team developed and implemented advanced instrumentation and control systems to dynamically route flows between new and existing treatment components.

Decades of previous expansions resulted in a congested and overly complex network of pipes at the WWTP. The design team streamlined this system, eliminating hydraulic bottlenecks, improving overall flow and reducing the risk of untreated discharges into Wildcat Creek.