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Indoor Water Use
Indoor Water Use
The average American family of four uses about 12,120 gallons of water per month, which is about 16 units (ccfs - hundred cubic feet) on your water bill. This is an estimate that includes both indoor and outdoor water usage averaged throughout the year. Like your energy bill, you may notice that your water bill fluctuates throughout the year. But unlike your energy bill, your water bill is lower in the winter months and higher in the summer months. This is due to outdoor irrigation and hotter, drier weather. And vice versa, your water bill will be lower in the winter months. Outdoor water use can account for 60-80% of your water usage during the summer months.

Toilets can account for as much as 30% of indoor water use, especially if it’s an old, high-flush toilet. Older toilets (manufactured before 1994) can use 3.5 to 7 gallons per flush (gpf). Newer toilets (manufactured after 1994) use 1.6 or 1.28 gpf, with some models using as little as 0.8 gpf. Bathroom and kitchen faucets, showers, and baths account for about 34% of indoor water use. Appliances such as clothes washers and dishwashers use about 25%.

There is one more source that most people are not aware of: leaks. Leaks can account for about 14% of water use...or shall we say water waste...in your home. A faucet dripping at one drip per second can waste 3,000 gallons of water per year. A toilet leak can waste 200 gallons of water per day, that's 73,000 gallons of water per year, twice as much as the average American person uses! Curious about how much water is wasted from leaks? Check out the American Water Works Association's Drip Calculator. Click here for information on how to check for and repair leaks.

Plumbing Standards

Federal Plumbing Standards

Federal plumbing standards require that all plumbing fixtures in your home are low-flow/flush. In 1994, the Federal Plumbing Standards for low-flow plumbing fixtures went into effect and are as follows:
  • Toilets - maximum flush volumes of 1.6 gallons per flush (gpf)
  • Sink faucets - maximum flow rate of 2.2 gallons per minute (gpm)
  • Showerheads - maximum flow rate of 2.5 gpm 

Some of you may remember when the standard first changed back in 1994, the technology wasn't fully developed and performance lagged. You may have needed to flush more than once or sacrifice low showerhead pressure. Fortunately, technology has advanced and the plumbing fixtures of today are very high quality with outstanding performance. Look for the EPA WaterSense labels that indicate water-efficient products that are backed by independent third party certification and meet EPA's specifications for water efficiency and performance.

California Plumbing Standards

As of January 1, 2014 the new California high-efficiency plumbing standards went into effect for all plumbing fixtures sold and installed within the state.  These standards are in line with the EPA WaterSense specifications and are as follows:
  • Toilets - maximum flush volumes of 1.28 gallons per flush (gpf)
  • Sink faucets - maximum flow rate of 1.5 gallons per minute (gpm) for bathroom faucets and 1.8 gpm for kitchen faucets
  • Showerheads - maximum flow rate of 2.0 gpm

How to Conserve Water in Your Home
  • Check for leaks regularly. Be sure to look under your sinks. If you think you're toilet is leaking, pick up free toilet leak detector tablets from our office.