Washington Suburban Sanitary Commission facility technician Steve Thomas uses a modified shopping cart to catch ’flushable’ wipes Wednesday before they get to pumps and clog sewer equipment in Greenbelt. (Jonathan Newton/The Washington Post)

Next time you go to toss that “flushable” wipe in the toilet, you might want to consider a request from your sewer utility: Don’t.

Sewer agencies in the Washington area and across the country say the rapidly growing use of pre-moistened “personal” wipes — used most often by potty-training toddlers and people seeking what’s advertised as a more “thorough” cleaning than toilet paper — are clogging pipes and jamming pumps.

Utilities struggling with aging infrastructure have wrestled for years with the problem of “ragging” — when baby wipes, dental floss , paper towels and other items not designed for flushing entangle sewer pumps.

The latest menace, officials say, is that wipes and other products, including pop-off scrubbers on toilet-cleaning wands, are increasingly being marketed as “flushable.” Even ever-thickening, super-soft toilet paper is worrisome because it takes longer to disintegrate, some say.

“Just because you can flush it doesn’t mean you should,” said I.J. Hudson, a spokesman for the Washington Suburban Sanitary Commission, which handles sewage for 1.8 million residents of Montgomery and Prince George’s counties.

1 of 8 Full Screen Autoplay Close Skip Ad × Things you shouldn’t flush... View Photos ...Or put in the sink. Caption ...Or put in the sink. Here are a few major culprits in clogging drains in municipal sewer systems, according to the Washington Suburban Sanitary Commission. Plumbers have provided a few more clogging culprits and pollution agents. 1. Baby wipes This is a clear No. 1, says the sanitary commission, even if the advertising says they are flushable. The commission adds that the other big cloggers are in no particular order. LotusWorks Buy Photo Wait 1 second to continue.

The result: Utility officials say crews needed for less-preventable sewer maintenance and repairs are being deployed instead to wipes patrol.

The WSSC has spent more than $1 million to install heavy-duty grinders to shred wipes and other debris before they reach pumps on the way to the treatment plant, Hudson said. Officials with DC Water, the District’s water and sewer agency, say that more than 500 man-hours have been devoted over the past 12 months to removing stuck wipes and repairing broken equipment. Anne Arundel County officials blame wipes on a 35 percent jump in broken pumps and clogged sewer lines over several years.

Wipes also contribute to blockages that cause sewage to overflow into streams and back up into basements.

This summer, a 15-ton glob of wipes and hardened cooking grease the size of a bus — and nicknamed “Fatberg” by the Brits — was discovered in a London sewer pipe after residents complained of toilets that would not flush.

What constitutes “flushable” might soon get federal oversight. Officials of the wastewater industry and wipe manufacturers say the Federal Trade Commission recently asked for data as part of an investigation into the “flushable” label. A spokeswoman said the FTC does not confirm ongoing inquiries unless it takes action.

Wipe manufacturers say they are trying to reduce wear and tear on sewer systems and septic tanks. A trade group, the Association of the Nonwoven Fabrics Industry, is forming a technical work group with utility officials to sort through differences over how wipes should be tested for flushability and how quickly they should be required to break apart.

The two sides have worked on the issue since at least 2007 but stepped up discussions this summer after the trade association released an updated “Code of Practice” for wipes manufacturers. The guidelines, which are voluntary, spell out seven tests that a product should pass before being marketed as “flushable.” They also suggest making “Do Not Flush” logos — an encircled person and toilet with a slash — more prominent on those that do not pass but are commonly used in bathrooms.

Beneath the feet of the Washington D.C. flows the waters of the once above-ground waterway-turned sewer, Tiber Creek. The Post's John Kelly took a dive into the D.C. sewer system to investigate this hidden waterway and shared what he found. (Brad Horn, John Kelly, & Sandi Moynihan/The Washington Post)

Dave Rousse, president of the fabrics group, said the primary problem lies with people flushing paper towels, baby wipes and other products not advertised — or designed — for toilets. Consumers want baby wipes in particular to be durable enough to withstand finger “poke-through,” he said.

“We all agree the solution to the problem is to reduce the burden on wastewater treatment systems,” Rousse said. “We agree we need to label products appropriately and educate the public to flush responsibly — to look for and obey disposal instructions.”

Utility officials say that one of the manufacturers’ key tests for wipes marketed as “flushable” does not simulate conditions in real-life sewer systems. The “slosh box” test requires that at least one-quarter of a wipe agitated in water be broken into pieces small enough to pass through a small sieve within three hours. However, utility officials say wipes can reach a pump within a couple of minutes. Moreover, many sewer systems, including the WSSC’s, move sewage primarily via gravity and are not nearly as hard on the wipes as the agitation test, utility officials say.

Manufacturers disagree, saying their newly streamlined tests ensure that wipes marketed as “flushable” are safe for sewer and septic systems.

“The industry has spent an incredible amount of time developing its test methods based on scientific evidence,” said Kim Babusik, a vice president for Nice-Pak, which manufactures flushable and non-flushable wipes for Costco, Target, CVS and other retailers.

Utility officials say they need to solve their differences soon. The wipes industry, catering to consumer demand for convenient personal and household cleaning products, is booming. In 2012, “tissue” wipes marketed as “flushable” accounted for about 14 percent of the $4 billion “pre-moistened”-wipes market, Rousse said. Consumer wipes sales are predicted to grow by about 6 percent annually for the next five years, he said.

So when in doubt, what should you flush?

It might sound blunt, but utility officials recommend sticking with the “three P’s”: pee, poop and (toilet) paper.