Final Report: Evaluation of Lead Service Line Lining and Coating TechnologiesEPA Grant Number: R834865
Title: Evaluation of Lead Service Line Lining and Coating Technologies
Investigators: Case, Traci L. , Adams, Craig D. , Peltier, Edward F. , Randtke, Stephen J. , Roberson, J. Alan
Institution: Water Research Foundation , American Water Works Association , University of Kansas
EPA Project Officer: Hiscock, Michael
Project Period: January 1, 2011 through December 31, 2016
Project Amount: $600,000
RFA: Advancing Public Health Protection through Water Infrastructure Sustainability (2009) RFA Text | Recipients Lists
Research Category: Drinking Water , Water
The objectives of this research project are to: (1) comprehensively evaluate lead service line (LSL) lining and coating technologies as alternatives to full or partial LSL replacement, and as a means of protecting and repairing both lead and copper service lines (CSLs); and (2) provide water utilities, engineering consultants, state regulators, consumers, and other interested parties with information and supporting documentation needed to make informed decisions regarding lining and coating of both LSLs and CSLs.
To accomplish these objectives, the investigators sought, as a secondary objective, to obtain and evaluate information on many different aspects of linings and coatings, including the following:
- Effectiveness in preventing lead release from LSLs and reducing tap-water lead levels
- Advantages and disadvantages for full versus partial LSL replacement
- Commercial availability, suitability for use in small-diameter pipes, and utilization of materials certified for use in contact with potable water
- Potential, upon installation and after aging, to leach organic and inorganic chemicals of concern with respect to water quality
- Long-term effectiveness and durability
- Ability to control internal water-service-line corrosion, prevent metal release from both service lines and the scales inside them, and repair service-line leaks
- Costs to both utilities and property owners, especially relative to the cost of LSL replacement
- Engineering feasibility, commercial availability, certification, and property access issues
Three currently available lining or coating technologies can effectively reduce or eliminate release of lead from LSLs, are expected to have a long service life, and can potentially result in significant cost savings and other benefits relative to LSL replacement, depending on site-specific conditions. Other possible benefits include fewer and shorter disruptions of vehicular and pedestrian traffic; reduced damage to landscaping, trees, sidewalks, and driveways; less potential for damage to other utility lines (gas, electric, phone, cable, sewers); and facilitating delay of LSL replacements until they can be more efficiently and more cost-effectively performed in concert with future main rehabilitation or replacement projects. Thus, lining and coating technologies are potentially useful tools for reducing public exposure to lead in drinking water. Public water systems and property owners should be encouraged to evaluate their use, to the extent permitted by applicable regulations, in situations where significant cost savings and/or other benefits can be realized; and, where applicable, to incorporate their use into well organized, system-wide LSLR programs to help minimize costs and maximize benefits.
Three technologies are deemed to be especially promising and are therefore recommended for consideration by both public water systems and property owners: PET lining, epoxy coating, and polyurea/polyurethane coating. Each can effectively reduce or eliminate lead release, is commercially available, and is, or has been, certified for use in contact with potable water in the United States, Canada, and/or the UK. Each of these technologies involves materials that could potentially affect water quality by leaching certain constituents into the water; but that is true of every material that is used, or could conceivably be used, in water service lines. This issue has been effectively addressed for many years by requiring any material that may come into contact with potable water in a public water system to be certified as meeting NSF/ANSI Standard 61.