As the nation's aging potable water pipeline systems fall deeper into disrepair, and costs of traditional pipe replacement increasingly dwarf societal abilities to pay for upgrades, innovative approaches to sustain pipeline assets are urgently needed. We have discovered that our existing pipe materials (i.e., iron, cement, and copper) have a remarkable ability for autogenous leak self-repair that has heretofore been unexploited, providing possible approaches to pipeline restoration at costs orders of magnitude lower than conventional alternatives. Our ultimate objective is to rationally engineer the chemistry of drinking water to seal existing leak-holes formed in existing materials via clogging with waterborne and/or water-formed particles. A laboratory phase of research establishes fundamental mechanisms of (1) leak clogging by model particulates commonly found in water distribution systems, (2) "smart" precipitation of crystalline CaCO3(s) in leak-holes, and (3) metallic corrosion as a pathway for repairing leaks. Parallel large-scale application of the approach to extend the lifetime of New York City's iconic Delaware Aqueduct will provide valuable data and insights to both leak clogging and "smart precipitation."
This research is the first to demonstrate that existing leaks in aged pipelines do not inevitably grow to failure, but can actually provide a pathway to self-repair via water chemistry. Such low cost, environmentally friendly solutions to one of the most urgent infrastructure problems facing the developed world, has the potential to save tens of billions of dollars per year in reduced damages, water loss, and capital expenditures. Repair of leaks enhances water conservation/sustainability and protects public health by reducing the likelihood of contaminant influx into pipelines. After more than a century of research aimed at minimizing problems with corrosion, scaling and particle formation in potable water systems at every opportunity, the possibility that these processes can be beneficially exploited to repair existing pipelines would represent a true paradigm shift. The basic science and concepts also have direct linkages to economically sustaining other decaying infrastructure assets including sewage pipelines and concrete structures.
