Woods Hole Infiltration Reduction Project

The Falmouth Wastewater Division implemented the Woods Hole Infiltration Reduction (Sewer Lining) Project in the winter of 2016 in order to reduce the amount of infiltration into the Woods Hole area wastewater system.  The project was successful in reducing infiltration into the sewer system by more than 50,000 gallons per day, thereby reducing the daily volume of wastewater pumped from Woods Hole by more than 35%.

Background

Much of the wastewater collection system in Woods Hole was installed in the late 1940s and early 1950s and consists of vitrified clay pipe and brick manholes. Groundwater can enter, or "infiltrate into," the sewer system through cracks in the pipe, separations at pipe joints, and gaps between bricks in the manholes. This infiltrated non-wastewater flow takes up valuable sewer system capacity and wastes electricity since it is pumped up to the treatment plant and goes through the treatment process.

Project

The Woods Hole Sewer Infiltration Reduction Project involved pre-cleaning and pre-inspecting the sewer mains and manholes, and then lining the pipes using "cured-in-place" pipe lining technology, and lining manholes with cementitious material. The pipe lining technology was "trenchless," which means that it was accomplished without excavation - a cloth pipe liner was pulled from one manhole to another, then cured in place. While each section of pipe was lined, wastewater was pumped around that pipe section, using a portable pump and temporary piping laid out along the ground surface ("bypass pumping").
This trenchless construction method was significantly less disruptive and less costly than excavation and complete replacement of pipes and manholes would have been. The new pipe is a fully structural pipe with a slightly smaller internal diameter but smoother surface, free of roots and cracks.