However, thanks to a group of concerned scientists and citizens who banded together in the late 60s and compelled our government to protect the environment against pollution and waste, the per capita use of water in the U.S. home has remained fairly unchanged since the late 70s. On January 1, 1970 Richard Nixon signed into law the National Environmental Policy Act, ordering the U.S. to “make peace with Nature.” While that mandate has been increasingly undermined in recent years, NEPA nonetheless caused reform in toilets and faucets, making them increasingly efficient over the decades.
In the 1950s the typical U.S. toilet used 7 or more gallons of water per flush. By the 1980s we were using 3.5. In 1995 legislation was passed requiring toilets to utilize only 1.6 gallons per flush. With the mandate came cries of dismay from clog-challenged households. Double- or triple-flushing became common.
But the situation has improved. After tweaking tank sizes and flapper mechanisms, the low-flush toilets of today are much more reliable than those of the 1990s. The typical toilets offered today include: gravity type, pressure-assist, and vacuum-assist.
Gravity toilets are the most common. The water pressure requirement for these is 10 pounds per square inch, so they work with all standard home plumbing. Since it is the force of gravity that provides the force in these models, taller toilets sometimes work better.
Vacuum-Assist toilets have a vacuum chamber within the tank that works to siphon the waste down and quickly replenish the water level in the bowl. These units are quiet, and their performance level is higher than gravity types, although they are as expensive as the pressure-assisted.
Pressure-Assist toilets have the most flushing power, but they require a higher water pressure of 25 pounds per square inch. If they are to be installed in an older home, the pressure should be checked first. These toilets tend to be expensive and shockingly noisy, but are the best of conventional toilets in getting the job done without continuous flushing.
Virge Temme
Several U.S. Manufacturers offer dual-flush toilets. Among them are Kohler, Sterling (a Kohler subsidiary), and Toto. An Australian company, Caroma, is also available in the U.S. Miso testing (spreading miso paste on toilet paper to simulate human waste) has been used to determine the most efficient of these dual-flush models. While other models performed admirably, the Caroma dual-flush offered the strongest flush with the lowest water use. The only drawback is that Caroma replacement parts can be more difficult to come by, and if you have problems your toilet could be out of service for longer than it might be with more available U.S. models. Keeping spare parts might be wise.
It has been estimated that the average U.S. household could save $50-100 per year by switching to a low-flow toilet, and more with dual flush models. Before racing out and buying the latest model, I encourage you to see if the toilet you already have can be retrofitted with a more efficient flushing mechanism. If not, do your research and before purchasing anything make certain the newer low-flush or dual-flush models can work over your existing trap (the pipes in the floor under your toilet), as newer models are sometimes longer than the old standard units.
As a final point, I can’t resist including mention of a sign I’ve seen in many Door County homes with holding tanks: “If it’s yellow let it mellow; if it’s brown flush it down!”…truly the ultimate in water-saving technology!