According to U.S. EPA, an average American family of four uses 400 gallons of drinking water every day. This amount can increase depending on location; for example, the arid West has some of the highest per capita residential water use because of landscape irrigation.  The government estimates that an average home, retrofitted with water-efficient fixtures, can save 30,000 gallons of water per year. If one out of every ten homes in the United States upgraded to water-efficient fixtures, it could save more than 300 billion gallons per year.  For example, did you know that toilets are the single largest water user inside a home?  A leaky toilet can waste 200 gallons of water per day, and EPA estimates that nearly 20 percent of all toilets leak.  EPA also estimates that an average household spends as much as $500 per year on its water and sewer bill, but could save about $170 per year by retrofitting with water-efficient fixtures and incorporating water-saving practices.