Toilets use more water in the home than any other appliance or fixture. About 30 percent of residential indoor water consumption "goes down the toilet." In addition, toilets often leak which becomes a major source of wasted water. WaterSense is a program sponsored by the United States Environmental Protection Agency (EPA) that helps consumers identify high-performance, water-efficient toilets that can reduce water / wastewater use and cost in the home and help save the nation's water resources.
Under U.S. Federal law, new toilets must not use more than 1.6 gallons per flush (gpf). High-efficiency toilets (HETs) go beyond the standard and use 1.28 gpf, a 20% savings (6 liters v. 4.8 liters). A few of the new toilets use even less, only 1.1 gallons (4 liters). The WaterSense label can be applied to HETs that are certified by an independent testing laboratory to meet strict criteria for both performance and efficiency. HETs must complete the third-party certification process to earn the right to bear the WaterSense label.
Everyone is concerned about the performance of low-flow toilets. Do they clear the bowl and leave it clean? Do they stop up frequently? Unlike the first 1.6 gallon / flush toilets, WaterSense HETs combine high efficiency with high performance. Advances in toilet design permit WaterSense HETs to save water without loss of flushing power. Many HETs actually perform better than standard toilets, a testament to the use of computers to design them rather than the trial-and-error guesswork of earlier designs.
High efficiency toilets save you money by reducing your water and wastewater costs. Over the course of a lifetime, an average person flushes the toilet nearly 140,000 times. If you install a WaterSense HET, you can save 4,000 gallons per year and your children can each save about a third of a million gallons during their lifetime. If a family of four replaces one 3.5 gpf toilet made between 1980 and 1994 with a WaterSense toilet, they can save $2,000 over the lifetime of the toilet. If the toilet being replaced was made before 1980, it uses 5 gallons per flush so the savings will be much greater.
With these savings, new high-efficiency toilets can pay for themselves in only a few years. Even better, many local utilities offer substantial rebates (up to $175) for replacing old toilets with HETs. Check with your utility company or municipality.
Whether you are remodeling a bathroom, beginning construction of a new house, or just want to replace an old, leaky toilet, a WaterSense labeled HET is your best bet. Look for the WaterSense label on any toilet you buy. If every home in the United States replaced just one old toilet with a new HET, we would save almost one trillion (spelled with a T) gallons of water per year, equal to more than two weeks of the water flowing over Niagara Falls!
Note that some manufacturers offer high-efficiency and ordinary models with very similar names, so be sure and look for the WaterSense label.
You will find that most of the big names in bathroom fixtures offer high-efficiency toilets, along with some newer companies. Familiar names include American Standard, Eljer and Kohler. Less-familiar manufacturers include Capizzi, Caroma, Gerber, Mansfield, Niagara, Sterling (Kohler), Toto, Vitra, Vortens and Western Pottery.
The City of Austin, Texas, maintains a list of 1.28-gallon high efficiency toilets that are approved for rebate at http://www.ci.austin.tx.us/watercon/toiletrebatelist.htm. This is an excellent starting point for selecting your new toilet.
The California Urban Water Conservation Council tested many toilets for performance in 2003. The results of those tests can be found at http://www.cuwcc.org/uploads/product/MaP-10th-Edition-Appendix-B-081507.pdf.
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