Why did those early low-flow toilets clog? Manufacturers begin to think “outside the bowl” to find a solution.

Early 1.6-gpf fixtures - to comply with early-1990s standards - decreased the size of the trapway in order to produce a sufficient siphon to clean and clear the bowl of waste. But in their rush, manufacturers inherently created a chokepoint in the toilets' tight - excuse the expression - colon-like channels.

Today, innovative design and testing capabilities have allowed manufacturers to relieve that traffic jam, all while lowering water consumption even further than mandated.

“Water conservation - especially for drought areas or septic systems - is imperative,” says James Walsh about the need to embrace low-flow fixtures. But Walsh, as director of residential toilets at American Standard, doesn't believe that functionality needs to suffer in order to save a few gallons. “We're constantly looking at ways to innovate, and also improve the bathroom experience for our customers.”

In the past 15 years (“Has it been that long?” Walsh asks), technology now is beginning to catch up to the design and engineering of functional low-flow fixtures.

“The material that makes up a toilet - vitreous china - is a difficult one to make changes to on a wide basis,” says Walsh. Previously, the nonabsorption quality of the clay could be altered only slightly without decreasing the material's integrity.

However, with American Standard's Champion model, the trapway could be widened to 2 3/8 inches, and it eliminated the tight 90-degree turn in the base. The company's Flush Tower mechanism in the tank makes it all possible with a release of a siphonic jet of 1.6 gallons of water into the bowl in just 0.75 seconds.

Unlike standard gravity-fed fixtures, siphonic jets create a swirling action in the bowl, which both pushes and pulls waste and water through the bowl. Also, the elimination of the conventional flapper design allows only the specified amount of water through the bowl, regardless of how long a user lay on the flush handle.

This year's innovation from American Standard, the FloWise two-piece elongated toilet, expands on Champion's features as a new high-efficiency model. It uses 20 percent less water but still performs effectively at 1.28 gpf.

“American Standard thought this was a better solution than a dual-flush toilet at this point in time,” says Walsh. “Mainly because you're not relying on the user.” Users, children especially, may select the wrong flush type and either end up using too much water for the application, or - more distressingly - not enough.

For commercial and institutional applications, the Ultra Flush® pressure-assist flushing platform from Gerber also utilizes siphonic jet action, and offers ultra-low-consumption at 1.1 gpf. It pressurizes the air inside the tank and drives water into the bowl for an efficient flush cycle. A contained vessel inside the tank eliminates sweating and keeps the floor dry.

“Ultra Flush toilets are perfect for high-traffic applications, which need extraordinary performance and minimal required maintenance,” says Kevin McJoynt, director of marketing for Gerber. Ultra Flush also features a large trap, averaging 3 1/8 inches on most models.

So how do you convince a customer to let go of his 3.5 gpf - or convince the skeptic who has come to detest the double-flushing of an older 1.6 gpf?

“Do a live demo,” says Walsh. “Customers can easily be convinced if they see the product in action; it's a big plus.” He suggests plumbers develop a relationship with a showroom or wholesaler that can offer a working model on its premises. Or, if his shop is accessible, a plumbing contractor can install an efficient low-flow fixture in his place of business and invite customers to see the results firsthand.