The Unilever facility in Jefferson City, Missouri, is a manufacturer of personal-care products such as soap and shampoo. The facility currently discharges 130,000 to 150,000 gallons per day of wastewater to the city’s wastewater and sewage collection-and-treatment system. The company has indicated that future flow rates of wastewater could be as high as 250,000 gallons per day.
When Unilever installed upgraded pretreatment equipment at the facility, it also considered installing a new 350-gallon-per-minute pump station nearby to reroute the discharge into a separate force main that would be built to connect to Jefferson City’s collection system at a pump station located about 1.5 miles north of the facility. Another option was to route the discharge to an abandoned, city-owned, 20-inch ductile iron force main, retrofitted to serve as a carrier pipe for a new force main dedicated to the Unilever pump station. The second concept would call for installing a smaller-diameter force main inside the abandoned main. Barr developed a concept-level design of this solution, along with opinions of cost for both options.