City Expands Treatment Capacity and Compliance

The City of Pekin wastewater treatment plant was operating with aged equipment, undersized for the capacity needs and was facing a compliance mandate deadline.

Furthermore, the City elected to concurrently address Long Term CSO improvements in an effort to minimize CSO events to the Illinois River. This project included upgrading the capacity and treatment capability of Plant #1 and the conversion and rehabilitation of the previously inactive Plant #2 to a CSO holding and capture facility. The project reflects the City’s commitment to environmental stewardship and preservation of the water quality of the Illinois River for future generations.

Farnsworth Group (as prime consultant) provided a full-service approach to the City for this project, including planning, funding analysis, design, computer simulation modeling, permitting, bidding, construction engineering and post-construction/startup phase engineering services for all aspects of the project - conception; planning; treatment process analysis; site civil, process, structural, mechanical/plumbing, architectural, HVAC and electrical designs; and instrumentation and controls upgrades.

The City of Pekin had two wastewater treatment plants, one (Plant #1) used for wastewater treatment. This plant had a design average flow capacity of 4.5 MGD and a maximum flow capacity of 8.7 MGD. The second plant (Plant #2) was inactive. The City was under a state regulatory compliance mandate for wastewater treatment facility repair/improvement. The wastewater treatment project included the conversion of Plant #1 to a design average flow of 6.84 MGD and maximum flow of 15.5 MGD. Coupled with the wastewater compliance mandates and capacity improvements, the City elected to concurrently address Long Term CSO Improvements within the scope of the project in an effort to minimize CSO events to the Illinois River from the existing older municipal collection system. Along with on-site CSO improvements at Plant #1, the project included the conversion and rehabilitation of the existing Plant #2 to a CSO holding and capture facility and provision for a high capacity CSO pumping and CSO pipe interceptor system.

The scope of the project included:

• wastewater collection, pumping, storage and treatment systems evaluation
• 20-year wastewater flow and loading projections
• treatment systems improvement or replacement recommendation
• treatment system alternative evaluation and recommendation
• development of construction cost estimates and schedule for the improvements

All improvements were completed under a comprehensive multi-year phased financial and implementation model.