Getting the Most (or Least?) From Your Toilet

Toilets use more water than any other appliance or fixture in your home, totaling approximately 30 percent of residential water consumption. And because toilets often leak, they can contribute to major water losses that often go undetected.

Designed for water conservation, high-efficiency toilets (HETS) have been defined by the plumbing industry and Environmental Protection Agency as those that use an average of 20 percent less water-per-flush than the industry standard of 1.6 gallons (or around 1.28 gallons per-flush.) Using a high-efficiency toilet can save up to 8,760 gallons of water each year for a family of four with six average daily flushes of water per person. In most municipalities this translates to a savings of $50 per year in water and sewer charges.

There are currently four types of HETS available.

• Gravity Fed Single Flush Toilets:  Gravity fed single-flush toilets operate the same way as any standard toilet, but use less total capacity per flush. (1.1 and 1.28 gallons).

• Dual-Flush Toilets:  Designed for light and heavy flushes, these operate with an average of less than 1.2 gallons per flush. They furnish the option of high or low flushes from 0.8 to 1.1 for the low flush and 1.3 to 1.6 gallons for the heavy flush. The choice of flush is made with a handle that can move up or down, or a two-button system giving the heavy or lower flush desired.

• Pressure Assist Toilets:  Pressure assist or pressurized tank toilets are another high-performance, low-consumption alternative. These utilize either water line pressure or a device in the tank to create additional force from air pressure to flush the toilet. The device in the tank could be a storage device with compressed air (would require replacement) or a tank that creates pressure when it is being filled. These typically average 1.1 to 1.2 gallons per flush and will move the volume of water more quietly.

• Power Assist Toilets: Power assist toilets operate using a pump to force water down at a higher velocity than gravity toilets and require a small fractional horsepower 110-volt pump to create the pressure. These operate between 1.0 and 1.3 gallons and are available as dual-flush models also.

Companies that produce these toilet options, such as Niagara Conservation or the Chicago Faucet Company, are available on the Internet.

If you want a simple but cost-effective method of cutting down on water use without replacing your existing toilet, try holding the handle of the toilet partly down for less than a full flush (this might take a little practice!). Or try inserting a “space user” to occupy water space in the flush tank. A plastic jug filled with water is a cheap alternative and stays in place permanently.


This article was condensed from the January 12, 2009 Water Efficiency Newsletter.