Centralized Treatment Facility

A customized approach in rural Wisconsin provides a unique, centralized treatment facility that is focused on the clients goals for today and tomorrow.


Although it’s common practice for dairy processing facilities to discharge wastewater to local municipal treatment plants (POTW), three (3) facilities in rural Wisconsin found a more effective solution by joining forces and constructing their own wastewater treatment plant (WWTP). For more than a decade, dairy processors in a rural Wisconsin city had been discharging their wastewater to the municipal treatment plant, which was no longer capable of handling the amount of wastewater being generated. Not only could the POTW no longer handle the current wastewater volumes, but it also meant that there was no opportunity for expansion for the dairy processors. After looking at options that included assisting with the building of a new POTW that was outside city limits, the processors reached out to The Probst Group to help with a solution that could effectively treat the wastewater from all three production facilities while still allowing for future growth.


  • Reduce phosphorus discharge to local watershed to meet stingent 0.07 mg/L limit.
  • Increase treatment capacity to allow for significantly more production wastewater to be treated
  • Provide a sustainable solution including energy production from the biogas generated by the anaerobic digestor
  • Address concerns of local residents including eliminating any odors from the WWTP and reduing/limiting ongoing truck traffic


Based on the extensive experience of The Probst Group, our team was enlisted to design and build the treatment facility. Probst handled every aspect of the project, including:

  • Permitting
  • Concept Design
  • Detailed Design
  • Construction Management
  • Commissioning
  • Training
  • Ongoing Operations

As the first industrial facility in Wisconsin to be subject to the ultra-low phosphorus limit of 0.075 mg/L, the state-of-the-art treatment plant design integrated multiple treatment methods to ensure that the facility is in compliance with discharge limits. Treatment components in the WWTP include:

  • Complete mix anaerobic MBR
  • High strength waste segregation with anaerobic treatment
  • Extended aeration activated sludge
  • Enhanced biological phosphorus removal (EBPR)
  • Multi-mode solids separator capable of servicing aerobic and anaerobic systems
  • Sludge dewatering
  • Advanced tertiary filtration
  • Bio-gas treatment and energy generation


In addition to allowing the facilities to have better control over their wastewater treatment, the innovative design also provides a source of renewable energy by capturing the bio-gas byproduct of the anaerobic treatment process. This renewable energy source has provided significant power generation and has allowed the WWTP to sell power back to the electrical grid.

Beyond just treating the wastewater, the centralized treatment plant has greatly reduced the amount of truck traffic through the city, as high strength wastewater is now able to be treated. Additionally, the vast majority of the load to the POTW has been removed, allowing the municipal treatment facility to function effectively.

The focus on creating renewable energy in the design of the WWTP has allowed for enough power generation to power more than 1200 homes.

Exceptional results from the treatment plant have shown the success of the wastewater treatment plant.

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