GreenLife score
EPA WaterSense puts the average American family’s home water use at more than 300 gallons a day. About 70 percent of that is indoors. Outdoor watering is roughly 30 percent nationally, and much higher in dry Western states during summer.
At 1 to 1.5 cents a gallon for water and sewer combined, 300 gallons a day comes to about $1,100 to $1,650 a year. That makes water a bigger bill than many people assume. Sewer charges are often based on how much water you use, so every gallon saved indoors is billed twice.
Where the water goes indoors
- 24%
- toilets, the largest single indoor use
- 20%
- showers
- 19%
- faucets
- 12%
- leaks, about 10,000 gallons a year in an average home
Source: EPA WaterSense, based on Water Research Foundation residential end-use data. Shares of indoor use.
Clothes washers take most of the rest. Dishwashers and baths are small by comparison. A modern dishwasher uses 3 to 5 gallons a load, less than washing the same dishes by hand.
Read your meter for hidden leaks
The EPA estimates that one home in ten has leaks wasting 90 gallons or more a day. Many of them make no noise. Your water meter is the fastest way to check, and the test is free.
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Find the meter
It’s usually in a concrete box near the street, in the basement or where the main line enters the house. Lift the lid with a screwdriver.
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Look for the leak indicator
Most meters have a small triangle, star or dial that spins when any water flows. If it moves with every tap closed, water is leaking somewhere.
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Do the two-hour test
Write down the reading, use no water for two hours, then read it again. Any change means a leak.
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Narrow it down
Close the shut-off valves behind each toilet and repeat. If the leak stops, it’s a toilet. If not, check faucets, the water heater relief valve, irrigation lines and the line to the street.
The usual suspects
A running toilet is the most common and most expensive leak. A worn flapper can let 100 to 200 gallons a day slip into the bowl, which is $400 to $900 a year at 1.2 cents a gallon. Put a few drops of food coloring in the tank; if color reaches the bowl within 15 minutes without flushing, the flapper needs replacing. The part costs $5 to $10.
A faucet dripping once a second wastes about 3,000 gallons a year. Usually the fix is a new cartridge or washer for $5 to $25.
Cheap fixture upgrades
WaterSense fixtures use at least 20 percent less water than standard models and have to pass performance tests, so they don’t feel weak. Replace old fixtures as they wear out, or sooner if they’re very old.
| Upgrade | Upfront cost | Yearly saving | Payback |
|---|---|---|---|
| Bathroom faucet aerators (1.5 gpm or less) Our pick | $2–$5 each | $10–$30 | Under 6 months |
| WaterSense showerhead (2.0 gpm or less) | $20–$50 | $40–$70 | Under 1 year |
| Fix a running toilet | $5–$25 | $70–$900 | First bill |
| Replace a pre-1994 toilet with a 1.28 gpf model | $200–$400 installed | $100–$140 | 2–3 years |
| Weather-based irrigation controller | $100–$300 | $40–$120 | 1–5 years |
Typical US prices in 2026; savings for a family of four at 1.2 cents a gallon for water and sewer, plus water heating at 17¢ a kWh where hot water is involved.
Outdoor watering
The EPA estimates that as much as half the water used outdoors is wasted through evaporation, wind and runoff from overwatering. Most lawns need about an inch of water a week, including rain. Set an empty tuna can on the lawn, run the sprinkler and time how long it takes to collect an inch of water. That’s your one-inch run time; split it into two waterings a week.
Rain barrels help with garden beds and pots but don’t hold enough to water a lawn. Replacing part of the lawn with mulched beds or native plants cuts outdoor water use more, and it means less mowing.
How water and sewer pricing works
Most utilities bill a fixed monthly charge plus a price per unit of water. A unit is often 1,000 gallons or one CCF, which is 748 gallons. Many use tiered rates, so the price per gallon rises as you use more. Cutting summer watering in a tiered system saves more than the average rate suggests.
Sewer charges are often based on your winter water use, when little goes on the yard. Some utilities offer a separate irrigation meter so outdoor water isn’t charged for sewer. It costs money to install, so it pays back mainly for large yards. Your bill or your utility’s rate page will show which system applies.
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How much water does a family of four use per day?
EPA WaterSense puts the average American family at more than 300 gallons a day at home, about 70 percent of it indoors. Households with efficient fixtures and little lawn often use half that.
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Why is my water bill so high all of a sudden?
The most common cause is a leak, usually a running toilet. Do a two-hour meter test with no water in use. If the meter moves, check the toilets first, then faucets and irrigation lines.
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What uses the most water in a house?
Toilets, at about a quarter of indoor use. In summer, lawn and garden watering often uses more than everything indoors combined, especially in dry states.
