Web Case Study! Cured In Place Pipe Lining Methodology Proves Viable Option for Outfall Repair
When the city of Detroit, MI, needed to rehabilitate the triple-barrel 63-inch diameter Helen-Jefferson outfalls into the Detroit River, there were few options. The sewer was a 100-year-old double-ring brick outfall, which, due to severe infiltration and inflow was in dire need of repairs. Missing bricks, holes in the sewer outfall sidewalks and brick deterioration caused severe leaking in the pipes, which now needed full structural rehabilitation and sealing.
Due to depth of the pipe and prevailing environmental conditions, and the fact that the pipeline flowed directly into the Detroit River, conventional open cut construction methods (dig and replace) were ruled out. Not only would this method be environmentally challenging, it would also have been high impact and more expensive. The city also considered another variety of slip lining called discreet barrel lining, which implements a smaller pipe that is pushed into the host pipe. This method was ruled out because of the resulting loss of hydraulic capacity, as well as concerns over efficient placement of an annular space grouting system, making it difficult to ensure grout placement. If grout is not used to fill in the annular space, the smaller pipe will not be secured, and movement and leakage may occur.