Modern Toilets Can Be Flush With Water Savings

East Campus pillars at enterance

Sept. 13, 2013

If you want to become more water-efficient in your home, start with the toilet. The Environmental Protection Agency reports that toilet use in the United States accounts for about 9,000 gallons of water used per person per year.

How can we be using that much water for toilets? A study by the American Water Works Association found, on average, each of us flushes the toilet five times per day. Older conventional toilets use 3.5 to 5 gallons or more of water per flush. Five flushes per day at 5 gallons per flush would add up to the 9,000 gallons per year reported by EPA.

Effective Jan. 1, 1994, the Energy Policy Act of 1992 required that all new toilets produced for home use must operate on 1.6 gallons per flush or less. That accounts for a savings of about 2 to 3 gallons per flush. Some of the first water-efficient models on the market did not effectively remove solid waste. In fact, it was often necessary to flush two or more times to effectively remove solid waste. Manufacturers responded, and pressure and vacuum assisted, or jet-action toilets were designed for good waste removal. The most water-efficient toilets carry the EPA WaterSense® label. Products with the label are generally 20 percent more water-efficient than similar products on the market. WaterSense® labeled toilets are required to use 1.28 gallons or less per flush.

Dual-flush toilets have been available in other countries for years, but they are relatively new here in the U.S. These toilets offer a half-flush (0.8 to 1 gallon) and a full-flush (1.6 gallons.) This allows you to use the half-flush for liquid waste removal and the full-flush for solid waste removal. Using only 0.8 gallons for liquid waste can add up to big water savings over time.

When an older toilet remains in use, you can place a plastic container (such as a plastic milk jug) filled with water or pebbles in the toilet tank to reduce the amount of water used per flush. Place the container to avoid interfering with the flushing mechanisms or the flow of water. A container can typically result in a savings of up to 1 gallon of water per flush. Do not use bricks or other objects that can release particles of soil, stone, or corrosive materials into the tank. In addition, a variety of devices are commercially available to either reduce the amount of water flowing into the tank, or hold back a reservoir of water when the toilet is flushed. When used with a standard toilet, the device may result in a savings of 1 to 2 gallons of water per flush. However, about 3 gallons of water per flush should be maintained for adequate flushing in older toilets.

You can save water by disposing of facial tissue, wipes, dead insects, and other waste in a trash can rather than a toilet. Use the toilet only to carry away sanitary waste.

Some water use attributed to toilets may not be from flushing. It is estimated that about 20 percent of toilets leak. Leaking toilets may make a telltale leak sound or the fill valve will open to refill the tank long after use. Any ripples or disturbance of water in the bowl can be a sign that the toilet is leaking. The best way to tell if a toilet has a leak is to place a few drops of food coloring in the tank. If the color shows in the toilet bowl after a few minutes without flushing, there is a leak. Leaks should be fixed. This usually involves changing the flapper valve. Toilets that don’t receive much use, such as in a basement, can leak unchecked causing significant waste. Make a habit of checking an unused toilet using the method described above or consider shutting off water to the toilet.

Sharon Skipton
UNL Extension Educator Emeritus
402-472-3662
Sharon.skipton@unl.edu

Bruce Dvorak, Ph.D.
Professor
Civil Engineering
402-472-3431
bdvorak1@unl.edu

Dan Moser
IANR News Service
402-472-3030
dmoser3@unl.edu