Hydraulic transients in plumbing systems

This study addresses the issue of pressure transients triggered within premise plumbing or a municipal water distribution system and their potential impact on drinking water service lines and plumbing systems. An instrumented experimental plumbing system was designed to examine the effects of a range of pressures commonly encountered in household plumbing systems. A transient triggered from within the household plumbing system structurally taxed the experimental service line and vertical plumbing sections but did not result in negative pressures. Taken together, these experimental results and observations of gaseous cavitation phenomenon with a high definition video camera demonstrated that a hydraulic transient triggered from a water main resulted in extremely low pressures events (up to −68.95 kpa) in the service line. This low pressure would be sufficient to allow the possible intrusion of microbial and chemical contaminants into the service lines. Homeowners and water utilities should be made aware of the importance of maintaining the structural integrity of their pipe systems and protecting the hydraulic integrity of water systems.