Wolverine World Wide, Inc. Wastewater Treatment Plant Modification


Wolverine World Wide, Inc.
Rockford, Michigan


Wolverine World Wide, Inc. (Wolverine) owned and operated a pigskin tannery in Rockford, Michigan. Wastewater generated from this facility was pretreated onsite and discharged to the city of Rockford sewer system. The city of Rockford sanitary sewer system discharges to the wastewater treatment plant via the North Kent sanitary sewer system.

The Wolverine wastewater treatment plant was modified to reduce onsite and offsite odors. Offsite odors were minimized by converting the plant to an activated sludge facility for biochemical oxygen demand (BOD) removal and nitrification, thus improving the effluent quality. This alleviated loading the oxygen-depleting compounds (BOD and ammonia) to the North Kent sanitary sewer system.

Modification to the wastewater plant included the following.

  • Segregated in-tannery wastewater discharges.
  • Added a 350,000-gallon, variable-depth reactor for alkaline catalytic sulfide oxidation.
  • Constructed a new, covered, primary clarifier and chemical conditioning tanks.
  • Added covered, aerated, sludge-holding and sludge-conditioning tanks.
  • Converted an existing equalization tank to covered, activated sludge with jet aeration.
  • Converted an existing thickener to a final clarifier.
  • Added new effluent flow metering station.
  • Added a 10,000-scfm, two-stage odor control scrubber.
  • Replaced electrical service, motor control center and instrumentation systems

The project required significant coordination and sequencing to allow continued wastewater treatment while modifying existing tanks and systems.


R&W performed the preliminary engineering work including the treatability work related to sulfide oxidation. As part of the preliminary engineering effort, cost estimates were developed for the proposed modifications. Following approval for the preliminary design and cost estimate, R&W was retained to design the improvements.

Wolverine used in-house staff to provide construction management services for project implementation. R&W worked with Wolverine to perform the project's construction management. Major equipment purchases were bid and pre-ordered for installation by subcontractors. R&W prepared multiple contracts and bid documents, and executed the bid for the wastewater plant modifications.


Project Schedule/Cost

R&W fees for this project totaled approximately $450,000.