Southside Interceptor Sanitary Diversion Project

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Unfortunately, work on the project had to be paused on May 21. This was due to difficulty with Amtrak's protracted review process associated with work to be performed near the edge of the existing railroad right-of-way. It was necessary to receive Amtrak's approval of the contractor's site specific work plan prior to performing work within their right-of-way that could potentially impact the railroad tracks.

Ultimately, the c​ontractor received all needed approvals from Amtrak on July 17. It was then necessary to negotiate revisions to the contract based on the recently received Amtrak approval(s).  Consequently, we expect work to resume on the project on Tuesday, August 6 upon the arrival on-site of an inspector from Amtrak to ensure the work doesn't conflict with the operation of the railroad.

Once work resumes, the contractor will work to fill in the excavation along the northerly slope leading down to the railroad tracks and re-open Fuller Street by August 21, as originally planned.

The project will then be idled until the spring of 2020. The work will resume after the U of M Winter Semester Commencement activities.

We expect that the project will now be completed in late-August 2020.​

​Project limits

Fuller Street between Glen Court and the Fuller Road/Glen Avenue/Fuller Street intersection.


Project Design:  completed February 2019

Expected Start of Construction: May 6, 2019​

Expected Construction Completion:  August 21, 2019

Why is this project being done

This project is being undertaken to divert excess sanitary sewer flow from the Southside Interceptor Sanitary Sewer (the major trunkline sewer that services a large portion of downtown and the westerly side of Ann Arbor) into the Northside Interceptor Sanitary Sewer. The diversion of the excess flow will eliminate sanitary sewer overflows during heavy rain events and reduce environmental damage from the overflows.

Work to be done​

The project will construct a 14' long x 12' wide x 12' tall, cast-in-place concrete, underground chamber that will divert excess flows by the use of a weir within the chamber.  The weir will be adjustable in order to accommodate future changes in sanitary flow patterns in the upstream sanitary sewer. The top of the underground chamber will be about 12' deep and its bottom will about 25' deep.  In order to construct this chamber, it will be necessary to excavate an extremely large hole within Fuller Street and the slope leading down to the railroad right-of-way.  As part of the work, it will also be necessary to relocate a portion of an existing 12" water main and a 24" diameter sanitary sub-main in the vicinity of the diversion chamber. 

Possible Impacts to residents​

Due to the nature of the construction and the needed location of the diversion chamber, it is not possible to maintain through traffic along Fuller Street during the work, therefore a deto​ur (PDF) will be in place. However, access to the U of M Parking Structure, as well as the residential housing units along Glen Court will be maintained to Fuller Street.  Glen Court traffic will be able to enter and exit from west of the project area.

Pedestrian traffic along the southerly side of Fuller Street will be maintained at all times. Access along Depot Street will be maintained to all local area businesses, Wheeler Park, and the Amtrak Station.

A detour route for Fuller Street traffic will be utilized as shown on the attached drawing. The project will also utilize portable, changeable, message signs to provide additional information and way-finding assistance to users of the area.

Information regarding the project has been communicated with Michigan Medicine representatives, emergency responders, and AAATA.  We are working with them to help minimize impacts and delays due to the Fuller Street closure.

This project will generate dust, noise, and inconvenience.  We apologize in advance for this unavoidable impact, but we will take all practicable steps in order to minimize these issues.

Costs and Funding Sources

The total cost of the project is expected to be about $1,734,000 and is being funded from Developer Offset Mitigation funds. 



​Michael Nearing
734.794.6410 ext. 43635 
Larcom City Hall
301 E. Huron St., Fourth Floor
Ann Arbor​, MI 48104​