Project Overview
The Oakland-Macomb Interceptor Drain (OMID) is a large diameter deep sewer system that serves over 800,000 residents of Southeastern Michigan. This sewer was constructed in-tunnel in the 1970s, and has experienced several catastrophic failures over the years, the latest in 2004. The OMID system consists of mostly 8-foot to 12.75-foot diameter sewer that ranges in depth from 30 to 110 feet. Based on NTH inspections from 2005 through 2008, many areas of the sewer were found to be in poor condition and could be subject to sudden failure. There is no redundancy in the system, so any collapse would disrupt service to the entire upstream population. Further, a collapse would affect millions more in terms of disruption of major roadway, and/or power supply.
In May of 2009, the Oakland Macomb Interceptor Drain Drainage District selected NTH to lead a team to develop an overall design approach for rehabilitation of the system, and to prepare contract documents for six (6) construction contracts that comprised the overall rehabilitation and repair program.
Project Scope
The scope of services for the program included geotechnical and geophysical investigations, 20 miles of sewer alignment survey, multiple full scale aquifer pumping tests, hydraulic evaluations, design of in- system flow controls, design of a 100 MGD pumping station, design of several major gate/access structures, design of two new (100 CFS and 120 CFS) pumps at the NESPS, emergency structural rehabilitation of the NESPS discharge chamber, Phase I and II environmental assessments, wetland assessments and permitting, easement assessments and procurement, and design for repairs to over seven miles of sewer.
Client Benefit
NTH is leading the design and construction administration team including on-site resident engineering, as-needed construction engineering, submittal reviews, contractor substitutions, pay applications, and community outreach programs.
