PC-755 – Oakwood CSO Control Facility - DWSD
Location: City of Detroit, MI
Start Date: June 2007
Finish Date: February 2012
Total Cost: $154 Million
The new combination storm and sanitary pump station and support facilities include control building, chemical feed facility, screen facility and odor control building. The project also includes the construction of two 4.5 million gallons CSO Basins and associated influent screen facility and odor control room; construction of a new effluent conduit from the CSO Basin to the local O’Brien Drain structure and various connections.
Project also included the installation of instrumentation, process controls, electrical and mechanical equipment; startup and hands-on training. Civil site work included the construction and installation of all required yard piping, landscaping, boundary fence and gates, internal roads, drainage and landscaping. Challenges on the project included the encounter of contaminated overburden underlain in excess of 70 feet of soft clay to fractured limestone producing artesian water with hydrogen sulfide.
Construction for the 70 feet deep pump station caisson required rock grouting through inclined holes in a grid pattern spaced 10 feet apart. A 3 feet thick slurry wall, supported with internal bracing was installed prior to the excavation and pile driving. Rock anchors were installed to prevent uplift of the empty caisson structure. Adequate dewatering system was provided during the installation of the slurry wall. Other challenges were working in limited area available to accommodate heavy equipment on site and the proximity to the