Inspecting systems for leaks, pits, and corrosion

Abstract

Old and new leak detection techniques were evaluated regarding their effectiveness in preventing water loss from metallic and prestressed concrete pipe.The National Research Council Canada (NRC) recently completed a project to assist the city of Montreal, Que., in determining the condition of its water and sewer system. NRC staff members reviewed available and future diagnostic techniques for both systems; conducted experiments on corrosion monitoring, closed circuit television inspection, and mechanical inspection methods; and provided general scientific advice during the course of the project. This article describes the results of the review of diagnostic techniques for metallic and prestressed concrete pipes. Both older techniques such as water audits and leak detection and new approaches such as acoustic emission monitoring and remote‐field‐effect inspection are discussed. Advantages and disadvantages of each technique are tabulated, and approaches are suggested for combining the techniques to diagnose a water system completely.