Forensic Study of a 96-in. PCCP Failure in Houston

In 2017, the City of Houston performed a condition assessment of an existing 96-in. water line in preparation for widening of Clinton Drive by TXDOT. Lockwood, Andrews & Newnam Inc. (LAN) was selected to perform the condition assessment that included installation of two temporary bag stops, three 96-in. butterfly valves, and select appurtenances, as well as performing electromagnetic testing, cathodic protection assessments, and internal inspections.Then in 2020, a pipe segment along this transmission line failed catastrophically impacting a large portion of the City. Contractors were mobilized and the repair process started almost instantly. Not long after the line was repaired, and back in-service LAN performed additional testing and a forensic study on the segment that failed and two adjacent segments that were removed. This paper will present the work performed and discuss the conclusions of the study at the end the process. Discussions will include nondestructive testing performed, destructive testing performed, and materials testing that were performed.