Engineers fashion a finer flush

Sun Journal

Toilets: New devices improve the old throne in response to the dual needs of water conservation and a clean bowl.

February 22, 2000|By Gary Dorsey | Gary Dorsey,SUN STAFF

Americans demand a well-flushed commode.

The humble pot barely evolved for most of the 20th century, but now environmental challenges presented by water shortages have threatened the white-glove standards of American bathroom habits and nudged toilet engineers against the unyielding laws of physics.

In 1992, conservationists persuaded Congress to pass a law reducing the water capacity of new toilets from 3.5 to 1.6 gallons. Consumers struggled with plungers and scrub brushes to assure an effective flush from their shallow tanks. People complained privately about having to flush twice with every use. An underground market grew for old toilets.

Rep. Joe Knollenberg, a Michigan Republican, heard the fury of a nation of double-flushers and introduced a bill to repeal the 1992 law. The nation, he says, should return to the satisfying whoosh of well-filled tanks.

"It's a great issue," says Knollenberg's press secretary, Paul Welday, "because it's one that Americans understand."

The congressman's campaign faces an uphill fight because the technology has improved and the law has saved water.

Still, those who have stood over a stained commode wondering how to expunge residue wonder why the industry has failed to build a better commode.

Engineering toilets, it turns out, is no simple matter. Ask the man who has done it.

Bruce Martin invented a pressure-assist device that has become one of the most popular new technologies in the business. But it was a long road to success. He compares the latest toilet engineering to the leap from DOS computer systems to Microsoft Windows technology.

"I walked into my first toilet plant and I thought I had gone through a time tunnel," says Martin, who runs W/C Technology Corp. in Farmington Hills, Mich. "I couldn't believe how archaic it looked. As it turned out, that was the state of the art."

A former physics student at Villanova University, Martin analyzed the dynamics of a gravity-assisted flush in 5-gallon toilets and, like any good entrepreneur, saw a way to improve the product and make a buck.

Harnessing untapped energy in a commode -- the pressure in the water line -- he made a device to compress air inside a tank and use the forced release of trapped water to blast water from tank to bowl. Comparing his new toilet to the old ones, he says, was like comparing a jet takeoff from an Air Force carrier to an airplane trundling down a taxiway.

The real beauty of his gizmo, as Martin saw it, was that a toilet needed only 1.6 gallons of water per flush.

"I never envisioned it as a ecological necessity," he says. "I thought of the savings businesses could make by lowering their water costs. For me, it was an economic opportunity. I figured in three years, I'd be able to retire."

The Western world's toilets had not undergone significant change since the days of Thomas Crapper, the 19th-century British plumber credited in legend with the invention of the so-called siphonic flush. At the time, Victorians simply left toilet water running to erase ugly deposits that stuck to porcelain. Like Americans in the 1990s, though, British authorities worried about water losses and encouraged plumbers to build a solution.

Although Crapper probably wasn't the inventor, by the 1880s plumbers across England were installing water closets that relied on gravity and the properties of a natural siphon.

The trick was to store water in a tank set high enough above the commode to send a tremendous gush into the bowl. The sudden press of water forced wastes through a hole at the bottom of the bowl and into a modified S-shaped pipe, creating a siphon that sucked the contents further down the sewage line.

Elegantly conceived, mechanically simple, the gravity-assist toilet thrived without significant change for more than 100 years.

Even in the latter half of the 20th century, as federal regulations lowered water capacities for toilets from 5 gallons to 3.5, no problems occurred. But in 1992, conservationists won an addition to the Energy Policy and Conservation Act restricting the flow of shower heads and toilets.

"It was back to the drawing board," says Peter DeMarco, team leader for product development at American Standard, one of the largest manufacturers in the country. "Everything was out the window and starting from scratch."

A $100 device that had performed yeoman service with the effortless lift of a flow valve suddenly required the expertise of engineers schooled in the science of hydraulics, computer modeling and mechanical design.

Gravity and 1.6 gallons of water would not flush the old gravity-assist toilets. Engineers evaluated ways to reduce the trap way size for better suction and studied national hygiene habits to gauge the amount of paper being flushed. They toyed with higher sides for toilet bowls, studied the cyclonic action of whirling pools and paid more attention to where waste falls into a bowl to make sure solids settled at the deepest point.

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