Northeast Interceptor-Truax Extension Relief Project

After receiving community input and conducting a variety of field investigation work, Madison Metropolitan Sewerage District has selected a final route for the Northeast Interceptor-Truax Extension relief sewer project.


The new sewer line, which will increase capacity and boost resiliency of the district’s wastewater collection system, will run from Highway 51 and Rieder Road to Lien Road. Bidding on the project occurred in February 2019 with construction anticipated to begin in July 2019. Total project cost is estimated at $9.6 million and will run in phases with project completion targeted for summer 2020.  Work will begin at Lien Road, and then proceed to the north.


The district and its contractors will work closely with City of Madison traffic engineers to minimize disruption to businesses and residents near the construction. Madison Metropolitan Sewerage District staff members also are working with City of Madison Parks officials to enhance Reindahl Park upon conclusion of the project.


Project will boost capacity, build resilience
The existing 48 inch pipe was constructed in 1969. Inspection of the pipe in 2011 identified corrosion of the interior concrete surface. The existing pipe is also nearing capacity. To meet anticipated growth, either a bigger pipe (called a replacement sewer) or a second pipe (called a relief sewer) working in parallel with the existing pipe is required.       

The selected project is the relief sewer option. Once the relief sewer is completed, the district intends to rehabilitate the existing pipe by inserting a new lining to protect against further corrosion. This construction strategy reduces risks and total project costs because building the relief sewer first minimizes the need for costly bypass pumping during construction. And ultimately, operating two sewer lines will enhance the resilience of the collection system.

It will be a big dig
When the project gets underway in July 2019, it will involve tunneling under East Washington Avenue and excavating at depths ranging from 20 to 45 feet. Traffic will be impacted on Lien Road between Parkside Drive and Thierer Road.
Selected Route


Community Involvement
Four different routes were presented on May 30, 2018 at a public meeting. Residents, members of the business community and property owners in attendance at the meeting provided feedback on the alternatives. The alternatives analysis was completed in June 2018, and Alternative 3 was the recommended route for the relief sewer. Alternative 3, which runs along the west edge of Reindal Park, was presented and approved by the City of Madison Parks Board at the June 13, 2018 meeting. The final selected route was presented at a community meeting on Wednesday, Oct. 17, 2018.  

For questions, contact Lisa Coleman, Madison Metropolitan Sewerage District project manager, or 608-222-1201 ext 133.