Jefferson sewer project enters final phase as St. Clair Shores detour continues into January

St. Clair Shores says the Jefferson Relief Sewer Project is entering its final tunneling phase, but southbound drivers and nearby residents will continue to face traffic restrictions along Jefferson Avenue.

A city update posted July 28, 2026, says final tunneling is scheduled to begin during the week of August 3. The remaining tunneling work is expected to be completed by January, but the city has not presented that timeframe as a guaranteed date for completion of the entire project.

Detour remains in place

The regional southbound detour remains unchanged. Drivers traveling through the affected area should continue using 11 Mile Road, Harper Avenue and 10 Mile Road instead of Jefferson Avenue through the work zone.

The southbound Jefferson Avenue lane closure will move slightly north as construction advances. Under the local access change, residents will not be able to travel south of Lakeshire Street on Jefferson Avenue. Drivers should follow posted signs and temporary traffic controls on Jefferson Avenue and connecting neighborhood streets.

The city’s update does not say that all Jefferson Avenue traffic is closed. The project page describes construction in planned stages, with traffic controls changing as work moves through different sections.

60-inch sewer beneath Jefferson Avenue

The project is installing a new 60-inch-diameter relief sewer beneath the southbound curb lane of Jefferson Avenue, from 9 Mile Road to Rio Vista. The city says crews are using micro-tunneling, allowing the sewer to be installed underground while limiting roadway excavation.

According to the city’s project information, the sewer is intended to increase system capacity, reduce the frequency and volume of sewer overflows, and improve water quality in Lake St. Clair.

The work is being carried out for the Southeast Macomb Sanitary District. Those long-term infrastructure goals come with continuing short-term traffic restrictions, including the regional detour and the local access limitation near Lakeshire Street.

Continuing impact near the Nautical Mile

In a May 26, 2026, report, WWJ Newsradio described concerns from St. Clair Shores residents, business owners and fishermen about traffic disruption near the Nautical Mile. The report included attributed concerns about speeding on neighborhood detour routes, child safety and possible customer losses for businesses during the busy season.

The July 28 city notice marks a new construction milestone rather than a new regional detour. A separate city notice from July 10 described paving work and temporary side-street restrictions while keeping Jefferson Avenue open to through traffic in that section.

For now, southbound drivers should allow additional travel time and continue using the 11 Mile Road-Harper Avenue-10 Mile Road route. Residents near Lakeshire Street should expect reduced southbound access on Jefferson Avenue while tunneling proceeds. The city’s expected January tunneling milestone may bring further changes to traffic controls, so drivers and residents should check later city updates for revisions.

Sources

• Jefferson Project in its final phase!
• Jefferson Relief Sewer Tunneling Project
• Major sewer project means Nautical Mile detour, traffic trouble in St. Clair Shores