Cedar Rapids Interceptor Repairs

During the flood of 2008 in the City of Cedar Rapids, several critical components of the City’s infrastructure were compromised. The City’s East Side Interceptor was one segment of sewer that incurred damage in the segment of the interceptor running through the heart of downtown Cedar Rapids. The Cedar Rapids East Side Interceptor includes 39 manholes and 11,080 feet of 36-inch, 42-inch, and 48-inch reinforced concrete and segmental block pipe which was heavily damaged during the 2008 floods. The primary goal of the East Side Sanitary Sewer Interceptor Repairs design project involved mitigating flood-related issues in order to return the existing interceptor to pre-flood condition.

HR Green evaluated alternative sewer rehabilitation technologies and methods available for use on the project. The feasibility and effectiveness of such methods were presented and discussed with the City, and a rehabilitation strategy was developed for the design project. 

Because the Cedar Rapids interceptor repairs were located Downtown, it was impractical to open trench and replace any of the pipes, so trenchless rehabilitation methods were the only feasible way to repair the damaged and leaking pipe. The interceptor repairs project included multiple rehabilitation methods including cured-in-place-pipe (CIPP) lining, point repair sleeves, cementitious manhole lining, and complete manhole replacement to mitigate issues associated with pipe and manhole infiltration and degradation.

In order for construction to take place, an intricate bypass pumping setup was necessary to bypass all of the affected sewer segments because the lining and manhole repair methods used could not be completed with an active sewer system. The bypass pumping was a major component of the project. With the setup of the 24-inch bypass piping through the center of downtown, utility conflicts, traffic control, public outreach, construction sequencing, and schedule maintenance were all critical elements to the success of the project.