Evaluating Technologies To Keep The Lead Out

With lead contamination still a paramount concern for consumers around the country, many water utilities need to improve their buried infrastructure sooner rather than later. For those that cannot embark on ambitious replacement projects, a new report on coating and lining technologies for lead service lines might be the guide forward.

Since late 2015, when a public health emergency was declared in Flint, MI, much of the country’s drinking water focus has been trained on the threat of lead contamination.

The daily work of treatment professionals and utility workers must confront a wide range of contamination issues, but many consumers are still preoccupied with the potential of their hometown becoming the next Flint. And their concerns are not misplaced.

An April 2016 study conducted by the American Water Works Association found that 6.1 million lead service lines (LSLs) serve up to 22 million people throughout the country. It may seem like a priority to fully replace those with new pipelines as soon as possible.

But, unfortunately, it isn’t that easy. It can be incredibly expensive to fully replace service lines (which is why some of our country’s drinking water infrastructure has been in place since World War II). In some cases, it may not even be legal for a municipality to replace the sections of lines that fall under private property. As a more feasible alternative, many drinking water providers should consider buffering LSLs with noncorrosive material.

“For specific situations where full lead service line replacement does not appear to be technically feasible, or economically or socially acceptable, lining or coating the customer-owned portion of the LSL should be considered as an option,” said Jonathan Cuppett, a research manager for the Water Research Foundation (WRF). “Potential benefits of lining and coating include reasonably long service lives, cost savings relative to LSL replacement, fewer and shorter disruptions to traffic, reduced damage to landscaping and driveways, less potential for damage to other utility lines, and facilitating delays of LSL replacements until they can be more efficiently and more cost-effectively performed.”

Assessing Options
To help drinking water utilities explore lining options to protect consumers from lead contamination, WRF put together a research project, Evaluation of Lead Service Line Lining and Coating Technologies.

Fully funded by the U.S. EPA, the six years of research that went into the publication of the project sought to evaluate lining and coating technologies as an alternative to full replacement of LSLs and copper service lines (CSLs) and to make recommendations about which technologies to pursue.

“To accomplish these primary objectives, the investigators sought … to obtain and evaluate information on many different aspects of lining and coating,” Cuppett said.

The researchers looked at each technology’s effectiveness at preventing lead release and reducing tap water lead levels, their commercial availability, long-term effectiveness and durability, costs to property owners, and more.

The technologies that WRF reviewed were chosen based on their history of success, required installation and return-to-service time, impacts on flow rate and pressure, and the potential to minimize disruptions.

From there, the researchers gathered and reviewed reports on lining and coating water service lines, collected information from water utility personnel and consulting engineers, and collected data from manufacturers.

It may go without saying, but a critical conclusion of this effort was that the idea of lining LSLs is a valid one and that the practice may be a critical aspect of how our water providers combat rampant contamination problems.

“Lining or coating technologies can effectively reduce or eliminate the release of lead from LSLs and may be useful in reducing exposure to lead,” Cuppett said. “Linings and coatings should be considered one of the tools in the toolbox when dealing with lead service line replacement issues.”

Winning Solutions
The project identified three particularly promising lead-abatement technologies and suggests them as the best options for utilities.

“PET [polyethylene terephthalate] lining, epoxy coating, and polyurea/polyurethane coating are deemed especially promising and are therefore recommended for consideration,” said Cuppett. The research also yielded some recommendations for utilities thinking of applying the technology.

“During the planning process, public water systems should identify potential needs and/or opportunities for use of linings and coating to reduce short-term and/or long-term exposure to lead, such as avoiding disturbances of historic sites or structures, environmental damage, traffic disruption, and interference with or damage to other utilities,” said Cuppett.

With so much buried infrastructure residing beneath private property, LSL replacement and rehabilitation programs will only be as effective as utility collaboration with the public will allow. Choosing a coating technology is only half the battle; the remaining half is establishing an effective consumer outreach effort.

“Public outreach will be an extremely important means of informing consumers and property owners about their ‘shared responsibility,’ including financial responsibility for replacing privately owned portions of LSLs,” according to the research report.

“Public water systems should provide information for consumers and property owners that emphasizes the importance of shared responsibility for minimizing exposure to lead, engages them in the planning process for the service area, clearly informs them about plans and progress to date, recommends actions they can or should take, and starts a dialog about possible financing options.”

Some utilities that can find the funding may decide that complete replacement is a better option, but for those that need to tackle lead contamination fast, without prolonged disruption of service, consider WRF’s report.

About The Author
Peter Chawaga is the associate editor for Water Online. He creates and manages engaging and relevant content on a variety of water and wastewater industry topics. Chawaga has worked as a reporter and editor in newsrooms throughout the country and holds a bachelor’s degree in English and a minor in journalism. He can be reached at pchawaga@wateronline.com.