Inside Your Home
Toilet flushing is by far the largest single use of water in a home. Many toilets use from four to six gallons of water for each flush. On the average, a dishwasher uses about 50% less water that the amount used when you wash and rinse dishes by hand if the dishes are prerinsed and if only full loads are washed in the dishwasher.
Without counting lawn watering, typical percentages of water use for a family of four are:
Toilet flushing – 40%
Bath and shower – 32%
Laundry – 14%
Dishwashing – 6%
Cooking and drinking – 5%
Bathroom sink – 3%
In the United States, the National Energy Act of 1992 requires low-volume toilets in new construction or as replacement in existing homes after January 1, 1994. Businesses were to have complied by 1997. Ultra low flow (ULF) toilets are available that use only 1.5 to 1.6 gallons for each flush.