Toilets The toilet is the single biggest water user in your home. Flushing accounts for about 38%, more than a third, of the water used within your home each day. Replacing an old model toilet with a new low-consumption toilet could automatically and permanently cut your home water consumption by 25% or more. New toilets require less than one-third the volume of water of older models. Low-flow toilets use a maximum of 1.6 gallons of water per flush compared with about 3.5 gallons of water used by a standard toilet. If you are not planning to replace an existing toilet, you can install water-saving devices such as a toilet dam. A toilet dam can be made by simply filling a small plastic water bottle and placing it in the tank. Be sure to place it away from the moving parts in the tank so as not to interfere with flushing.