A regular toilet can use 3.5 gallons per flush (gpf) where as a high efficiency toilet only uses 1.6 gpf or less. These efficient toilets have been marketed in the US since early 1980 and have been shown to reduce water use by 23% – 46% in residential homes! By 1992, 17 of the 50 states made it standard for replacement toilets and those installed in new construction to be 1.6 gpf.
In the same year, the Energy Policy Act (EPA) of 1992 established a national manufacturing standard of 1.6 gpf for most toilets. This act began to take effect in 1994 and significantly decreased water demand and wastewater generation; which also meant a reduction in the capital investment needed for water supply and wastewater treatment.
A 1999 study by the American Water Works Association Research Foundation looked at the water use in nearly 100 homes in each of 12 Northern American cities and found that high efficiency toilets save an average of 10.5 gallons of water per person per day! For a four person home, that’s 42 gallons of water a day and 15,330 gallons of water a year! Or, 672 of those 8oz glasses of water you’re supposed to drink every day!