Evaluation and Assessment for Interceptor Sewer Main that Runs Beneath and Adjacent to an Active Railroad Line
The City of Newport, Rhode Island selected Weston & Sampson to provide engineering services to evaluate and provide an assessment report for an existing 18-inch diameter interceptor sewer main that runs beneath and adjacent to an active railroad line. A portion of the existing sewer line passes beneath a historic cemetery. The project area also abuts a dense residential area and the busy downtown Newport. The line was subject to surcharging and was known to be subject to significant debris, including large boulders dropped into the system by vandals. The conditions compromised the ability to inspect the line to determine the pipe condition.
Weston & Sampson’s project included a work plan to complete television inspection of 2,500 linear feet of the main and 10 manholes within the limited access railroad right-of-way. Our follow-up evaluation included considering pipe maintenance and repair options, replacement and bypass/relief options, rerouting of flows to new and existing pump stations, and other considerations to move the flow away from the troubled alignment. In the report, Weston & Sampson recommended both short- and long-term actions to help the city address the pipe conditions and operational risks, while making long-term improvements consistent with the City of Newport’s long-term Combined Sewer Overflow (CSO) control plan.
Following the city’s consideration of the evaluation report and options presented, Weston & Sampson was chosen to design and bid the recommended improvements to the interceptor. Weston & Sampson finalized the design and construction was completed in Fall 2010.