A Look Back: Analyzing the Results of LWC’s PCCP Condition Assessment Pilot Projects

• Published in: Pipelines 2015 pp. 943 - 953
• Main Authors: Pike, Dennis, Gathof, Tony, Williams, Andrew F
• Format: Book Chapter
• Language: English
• ISBN: 0784479364; 9780784479360
• DOI: 10.1061/9780784479360.087

In 2009, a 60-inch (1500-mm) prestressed concrete cylinder pipe (PCCP) transmission main carrying potable water failed. This break and the hundreds of thousands of dollars in damages inflicted was the impetus for Louisville Water Company’s (LWC) PCCP Condition Assessment Program. The program covering 105 miles (169 km) of PCCP pipe was approved as part of LWC’s 2010 Capital Improvement Budget and contained two pilot projects that were selected. A 5.2-mile (8.4-km) section of 48-inch (1200-mm) pipe and an 11.5-mile (18.5-km) section of 60-inch (1500-mm) pipe were selected as the two pilot projects based on their perceived criticality, lack of redundancy, damage-causing capability, and the availability of electromagnetic inspection technology. These two projects were inspected with a variety of electromagnetic inspection platforms, high definition (HD) video, and acoustic leak detection technologies. The inspections identified several pipe sections that required a variety of testing, replacement, and rehabilitation options. LWC utilized multiple contractors to employ a variety of repair methods including external steel bands, external post-tensioning tendons, full joint replacement, internal carbon fiber-reinforced polymer (CFRP) linings, and internal hybrid fiber-reinforced polymer (FRP) linings. With the completion of both pilot projects, the paper will discuss all of the issues encountered, items that worked well and those that did not, a comparison of the multiple structural repair methods, data storage issues, LWC’s future implementation of the program, and how the program best serves LWC’s customers going forward.