In situ remediation of leaks in potable water supply systems

Water leaks in distribution system mains and premise plumbing systems have very high costs and public health implications. The possible in situ remediation of leaks while a pipeline is in service could reduce leaking at costs orders of magnitude lower than conventional pipe repair, rehabilitation, or replacement. Experiences of Roman engineers and recent field observations suggest that such processes can occur naturally or may even be engineered to ameliorate leaks, including those caused by metallic corrosion. Three mechanisms of in situ leak remediation (i.e., metallic corrosion, physical clogging, and precipitation) are described in this paper, in an effort to understand the role of physical factors (e. g., temperature, pressure, and leak size) and water chemistry (e. g., pH, alkalinity, corrosion inhibitors, dissolved oxygen, and turbidity) in controlling in situ remediation for both inert (plastic and aged concrete) and chemically reactive (new concrete, copper, and iron) pipe materials. Although there are possible limitations and uncertainties with the phenomenon, including the fraction of pipeline leaks to which it might apply and the durability/longevity of remediation, such approaches may prove useful in economically sustaining some aging drinking water infrastructure assets and reducing future failure rates.