Detroit Wastewater Treatment

MMI provided engineering design services for utility relocation under Cobo Hall, for the City of Detroit. This expansion required the Lodge Freeway, which passes under Cobo Hall, to be lowered and existing utilities to be relocated.

Two types of material were specified for the water main relocation The 16-inch water main material was ductile iron, Class 56, encased in polyethylene, whereas, the 30=inch water main was constructed of pre-stressed concrete embedded cylinder pip with rubber and steel joints. Approximately 1,633 feet of the 16-inch water main was installed in two phases. Of the 1,633 feet, approximately 225 feet of the 16-inch water main was placed in a casing pipe, which was “bored and jacked” with the remaining water main stalled by “open cut”. The pre-stressed concrete pipe totaled approximately 374 feet with 330 feet placed by “open cut” and 44 feet constructed by the “bore and jack” method. Both sizes required gate valves, tees, bends, closers and reducers; and thrust restraints were provided by encasing the respective items. Design of all of the water mains was coordinated with all utility companies, the City of Detroit, and the client, Michigan Department of Transportation. Construction costs totaled $7M.