CON-149 Emergency Rehab of Northwest Interceptor | 2020 WWD Top Projects

The Northwest Interceptor sanitary sewer in Detroit, Michigan was due for rehabilitation. Located in residential area, the 2,700 linear feet of 6 foot, 3 inch sanitary sewer posed challenges for workers due to regular flow. This project constructed a flow control gate and two flow control chambers to divert flow so the pipe could be inspected. With manned entry, workers found the pipe to be in terrible condition and on the verge of collapse, which required swift action from the Great Lakes Water Authority to rehabilitate the interceptor.

Mini Panicker, GLWA engineer and project manager, stressed the importance of this project to the nearby residential community. Steve Zajdel, senior project manager or Inland Water Pollution Control, discussed how safety was taken into account during the project. Fritz Klingler, president of FK Engineering, highlights the nuances required to ensure project success given all potential complications, and Karen Ridgway, president and principal engineer of Applied Science Incorporated, talked in depth about considerations for the flow control gate and flow control chambers.

Intro: (0:00)
Project background and GLWA history: (0:49)
Challenges the pipe size and length posed to rehabilitation: (1:59)
Importance of determining pipe condition prior to work: (3:38)
Location complexities and flow in the pipe: (4:48)
Options for diverting or controlling flow for the project: (6:04)
How the diversion gate became a guiding principle of the project: (7:30)
Inspection reveals cracks and potential for collapse: (9:18)
Considerations and purpose of constructed flow control chambers: (12:29)
Flow control opens doors to spray repair: (15:08)
Maintaining safety in the decaying pipe: (16:48)
How the pipe was sprayed for rehabilitation: (18:00)
Considerations for reinforcing the pipe in addition to the spray: (19:37)
Where are things now?: (21:06)
Outro: (21:36)

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