The Low Flow’s False Flush

The water-saving benefits of many aging low-flow toilets are spiraling down the drain. According to a new University of Arizona study, poor design and the tinkering of do-it-yourself plumbers have reduced the toilets’ effectiveness.

There"s no question that low-flow toilets save water, but they"re under attack for not working properly.Briggs 

Subject to potshots by Jerry Seinfeld and other comedians because of their dubious flushing performance, low-flow toilets became mandatory in the U.S. in 1994. They’re supposed to use less than 1.6 gallons per flush.

But nearly 27 percent of the toilets surveyed in the Tucson area used more than 2.2 gallons per flush. About 14 percent required double flushing at least once a day, and 12 percent had recurring leaks. Although the researchers remain supportive of low-flow toilets, their findings play into an ongoing debate in Congress, in which some lawmakers want the federal government to stop regulating toilet design.

Because toilet bowls typically use more water than any other home fixture, the discovery that they are flushing more than expected may mean that water utilities’ long-range planning is out of kilter with actual water use. “Most of them work just fine when they’re new,” says co-author Gary Woodard. “But as they get older, a significant number do develop one or more problems.” The researchers urge the plumbing industry to adopt stricter and more uniform standards for low-flow toilets that will make them more resistant to consumer tampering.

After passage of the 1.6-gallon standard, most toilet manufacturers simply fiddled with the inner workings of their 3.5-gallon tanks. Two popular techniques were to use “early close” flush-valve flappers that shut quickly, or to install a “toilet dam” that retained water in the tank and reduced the amount of water flushed. Time and consumer ignorance can reduce these toilets’ effectiveness. With a sharp pair of scissors, for example, consumers can easily trim the plastic toilet dam and increase the water flow. And when the “early close” flappers wear out, many consumers wind up installing a standard flapper that flushes 3.5 gallons.

Plumbing industry officials blame the federal government for rushing implementation of the 1.6-gallon standard. “Toilet design hadn’t changed much in years and years, and then all of a sudden the federal government said, ‘Change everything and do it yesterday’,” said Claudia Harris, director of government relations for the Plumbing-Heating-Cooling Contractors National Association.

Many environmental groups continue to champion low-flow toilets, because of the incredible potential for water savings. And they say the problems are overblown. According to the Conservation Law Foundation, “Although a number of well-documented studies have demonstrated that the ultra low-flow toilets have equal or better performance than older toilets, the trade is stubbornly resistant.”

The industry says that the newest low-flow models function well and that improved toilet standards should be adopted later this year.