Sewer district warns of rising treatment needs, $70 million upgrade and chloride limits

Eric, the Mass Metropolitan Sewage District executive director, told Monona’s Public Works Committee the district is planning a major liquid‑processing upgrade to handle increasing strength in its wastewater and to protect treatment reliability.

The district — which Eric said serves 24 customer communities and cited roughly 440,000 people in its current service area — is moving forward with a biological treatment upgrade it estimates at about $70 million to meet projected loadings over the next two decades. "This project is about $70 million," Eric said during the appearance. He added the project will be bid this summer so the district can refine its budget assumptions.

The district is unusual, Eric said, because 100% of its flow is moved by pumping rather than relying solely on gravity. That makes energy costs and system redundancy key operational concerns. "If we don't have [power], everybody's day goes down," he said, framing the importance of the district's heat‑and‑power and biogas projects to offset rising energy bills.

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