Problem: The City of Naperville South Operations Center (SOC) Pump Station was originally constructed in the 1960’s and upgraded in the 1980’s. For the past several years, the station had been experiencing capacity and reliability problems. During the preliminary engineering phase of this project, it was determined that the station capacity should be increased from 15 MGD to 24 MGD. This critical pump station needed to remain fully operational throughout construction.
Solution: Various alternatives for increasing the capacity and reliability of the station were evaluated. The structural condition of the station was also investigated. The selected alternate involved replacing the four existing dry pit, vertical, centrifugal pumps with five dry pit submersible pumps. Completely new piping, valving, variable frequency drives, and a 3-ton bridge carne were installed. The design included elaborate sequencing and piping configurations to maintain the station in service during construction.
The SOC Pump Station Upgrade to 24 MGD was completed on time and within budget. The project resulted in a capital cost savings of approximately $2,000,000 compared to the construction of a new pump station. The City of Naperville Department of Public Utilities Engineering and Operations staff played an integral role in the project from the preliminary engineering phase where they advocated use of the existing station, through final design where they provided valuable input with regard to pump selection and piping layout, and finally during construction where they provided day-to-day on-site construction observation. This project truly represents a team effort between the client/owner and the engineer.