Issue Date: May 11, 2015
Wet Wipes Clog Sewer Systems
Once reserved for babies’ bottoms and toddlers’ fingers, wet wipes have found a market with consumers bent on keeping their backsides feeling fresh. But the premoistened personal wipes, now ubiquitous alongside toilet tissue in the supermarket aisle, are causing problems for wastewater plant managers. They bemoan wipes’ incompatibility with sewage treatment technology and the millions of ratepayer dollars they’re forced to spend each year to pluck gobs of wipes out of their systems.
For instance, in Washington, D.C., where municipal pipes are old and small, flushed wipes can build up and create blockages as soon as they enter the sewer system, says Hiram Tanner, pumping manager at the District of Columbia Water & Sewer Authority. “We have to send someone out to clear out the sewers.”
Wipes that pass through pipes can get hung up in the city’s wastewater equipment. “We have to clean the pumps out and repair them,” Tanner says. And those that make it past the pumps get caught in screens that city employees clean with pitchforks.
The Washington wastewater authority has plenty of company in considering wipes a costly nuisance. Some utilities are striking back. Last month, the city of Wyoming, Minn., filed a federal class-action lawsuit against six makers of pre-moistened flushable wipes for alleged harm to their infrastructure. Brought on behalf of cities grappling with similar problems, the lawsuit seeks $5 million in damages and a declaration from the court that the wipes advertised as flushable are not safe for sewer systems. Defendants named in the lawsuit include Procter & Gamble, maker of Charmin wipes, and Kimberly-Clark, which produces Cottonelle wipes.
The lawsuit cites examples alleging damage from flushed wipes to municipal wastewater treatment systems in Denver; Orange County, Calif.; Raleigh, N.C; and San Antonio, Texas, among others. In New York City, the Department of Environmental Protection has spent more than $18 million over the past five to six years to remove the wipes from its facilities, according to Deputy Commissioner Vincent Sapienza.
Kimberly-Clark doesn’t comment about ongoing litigation, says company spokesman Bob Brand in an e-mail. He adds, “Field studies of actual material collected in a sewer showed that approximately 90% of the material found in sewers was not meant to be flushed.” P&G declined to comment.
In addition to utilities, consumers too are suing makers of flushable wipes, bringing at least four class-action lawsuits since last year. Plaintiffs in these cases have alleged that they were misled by the claims by manufacturers that wipes were flushable, claiming damages to household plumbing, sewers, and septic systems.
The cases bring into focus a key issue—how to determine what makes a wipe flushable. There isn’t a regulatory definition for the term. Manufacturers call wipes flushable based on a measure of dispersibility—how well a wipe falls apart when jostled in water.
The wastewater utilities’ lawsuit cites a field test that appears to show that wipes sold as flushable remain intact under conditions found in sewer systems. However, it is not clear if the plaintiffs have undertaken forensic analyses to sort wipes taken from sewer systems into products advertised as flushable from other wipes, such as those intended for babies or to clean surfaces, that manufacturers never intended consumers to flush.
“We agree that there are issues out there. We have great empathy for what the wastewater industry is facing,” says David Rousse, president of the Association of the Nonwoven Fabrics Industry (INDA). This trade group represents wipe manufacturers including P&G and Kimberly-Clark. “But there are many, many kinds of wipes,” Rousse points out. INDA is aware of the Minnesota lawsuit, but it is not involved, he adds.
Unlike toilet paper, which is usually made from natural or recycled cellulose fibers, a wet wipe may be made from cellulosic or synthetic fibers, depending on its intended use. Personal wipes made for flushing would be made from cellulose with a degradable binder, says Chris Luettgen, associate director of the Renewable Bioproducts Institute at Georgia Institute of Technology. Luettgen worked in product development at Kimberly-Clark for 19 years.
Other types of wipes may be made entirely from synthetic fibers, he says. These are “highly bonded, entangled, very long fibers that are not going to disperse.”
From 2008 to 2013, sales of flushable wipes alone grew 23% to reach $367 million, according to market research cited by Bloomberg News last year. The market for nonflushable products includes baby wipes as well as pet wipes, nail polish remover wipes, and car tire wipes. Rousse insists that it’s these nonflushable wipes, along with paper towels and feminine care products—and not the wipes sold as flushable—that are getting caught in wastewater treatment systems.
Sewer system operators see things differently.
“It’s an exaggeration to say that it’s not the flushable wipes causing the problems,” says Cynthia A. Finley, director of regulatory affairs with the National Association of Clean Water Agencies, an advocacy group that represents publicly owned sewage treatment plants.
Regardless of the arguments by manufacturers and sewage utilities, one thing has become clear: With so many different types of wipes out there, consumers are confused about what they should and should not flush.
INDA has established standards for what’s flushable and for product labels, but Finley says they aren’t good enough. Her organization is working with INDA to develop the next generation of standards, which are planned for June 2016, she says. “We’re trying to work together to improve labeling and education,” Finley adds.
Voluntary labeling that indicates wipes are nonflushable is inconsistent, even among larger manufacturers, says Aubrey Strause, a stormwater management consultant and past-president of the Maine Water Environment Association (MEWEA).
Strause maintains an inventory of wipes manufacturers, brands, lot numbers, packaging claims, and physical properties that she started in 2009. That information is invaluable when she collects and sorts soiled wipes from treatment facilities for forensic evaluations, she says.
Last year Strause led MEWEA (formerly the Maine Wastewater Control Association) in a pilot campaign with the nonwoven fabrics industry group to teach consumers that they should not flush baby wipes. They broadcast amusing game-show format ads called “What the Flush?” in which players are asked whether common items are flushable.
Her team collected and sorted wipes from a designated pump station in a suburb of Portland, Maine, for six weeks before the ads were broadcast. After an eight-week break for the media blitz, the team returned to the pump station to collect and sort wipes for another six weeks. They saw a significant decrease in baby wipes.
“When you do funny outreach to consumers, they will stop flushing baby wipes,” Strause says. But it’s temporary, she adds. The decrease only lasted for about four weeks after the media campaign ended.
Strause says she’s not comfortable calling the campaign a complete success and has not yet finalized her report on it. But she continues to worry about how wipes affect sewage systems. “Infrastructure is continuing to get worse,” she says, of the wastewater management enterprise.
“We have to take $30,000 to put in grinders” for wipes, Strause says, when the money was supposed to go toward sewer rehabilitation. “I have a hard time accepting that it should be the sole responsibility” of wastewater treatment plants.
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