A Successful CIPP Lining Project Extends Watermain Lifespan and Minimizes Disruption in Cambridge

Abstract

In 2024, the City of Cambridge completed a Cured-in-Place Pipe (CIPP) lining project for the watermain on Holiday Inn Drive which was nearing the end of its service life. This project involved rehabilitating 1,359 meters of mainline watermain, replacing 29 valves, 10 hydrants, and 28 large diameter service reinstatements. The goal was to extend the watermain's lifespan by at least 50 years, minimize future water breaks that will result in less disruptions to nearby businesses, leakage, and improve water quality and flow characteristics. During the design phase various CIPP lining technologies were reviewed to determine the preferred rehabilitation methodology, pulled-in-place installation of cured-in-place thermosetting resin liner with steam as the curing heat source. This method was selected for its structural integrity, rapid installation, minimal surface impact, and ease of reconnection of large diameter services. Several key risks were identified and mitigated during the project. Sideline tee connections were managed by backfeeding the sidelines, and connections to existing watermains were handled by installing new limit valves to avoid traffic impacts and ensure safety. Coordination with large water users, such as businesses, restaurants, hotels, schools, and churches, was critical to ensure uninterrupted water service during the works. Temporary watermain layouts and phasing plans were developed to maintain water service throughout the project. The project was completed on time and under budget, with no significant water supply complaints from any industrial or commercial properties. The City’s approach to using CIPP technology and strategic planning allowed for a successful rehabilitation of the watermain with minimal disruption to traffic and local businesses.