How much Water does a Faucet Use?

Faucets come in different sizes and shapes, and water pressure can vary between different places, but water flow rates are usually within a certain range.

On average, a faucet can use anywhere between 4-8 liters per minute (1-3 gallons per minute). This can depend on a number of different factors from the available water pressure to the age of the faucet and pipes. Newer faucets tend to have smaller flow rates than older ones because of improved standards and the use of aerators. Aerators are the small mesh screens at the end of faucets that allow air to mix in with the flowing water. They decrease the amount of water needed to get the same result by breaking up the water stream into smaller ones as it comes out of the faucet.

How can I measure the water flow rate from a faucet?

It is really easy to measure the flow rate of water coming out of any faucet. All you need is a water bottle or container of a known volume and your phone stopwatch. Here are the steps:

  1. Open your faucet to the flow rate you want to measure.
  2. Place the water bottle or container under the faucet and start the stopwatch on your phone at the same time.
  3. Stop the time on the stopwatch as soon as the container is filled.
  4. Calculate your flow rate using the following formula: Rate=Volume/Time. Multiply the rate by 60 to convert to minutes.

Useful tips:

  • Open the faucet to the maximum rate to get a consistent result that you can compare to other measurements (or even your own measurements later on).
  • Use a bigger container for more accurate results. This allows you to keep the water running for a longer time. A gallon (3.785 liters) is a great example.

Here’s an example of how I measured the water volume flowing out of my kitchen and bathroom faucets:

I used a 1.5 liter bottle and my phone. It took about 11 seconds for my kitchen faucet to fill the bottle, while my bathroom faucet only took 9 seconds. To calculate the flow rate, I divided the bottle volume (1.5 liters) by the time (11 or 9 seconds) and then multiplied the result by 60. This gives 8.2 liters per minute for my kitchen faucet and 10 liters per minute for my bathroom faucet. Keep in mind that I live in a new building where the water pressure is high, so your results might be less.

How much water does a bathtub faucet use?

On average, a bathtub faucet runs at 15-26 liters per minute or 4-7 gallons per minute. Bathtub faucets do not require flow restrictions like other faucets because they don’t run continuously. If you’re feeling bad about it, you shouldn’t. A bathtub can use less water than some showers. For example, a bathtub can take about 160 liters or 42 gallons of water, but people usually only fill it up to 113 liters or 30 gallons. That is the same water used in a shower running at 9.4 liters per minute or 2.5 gallons per minute for 12 minutes. Next time you take a bath, try filling your bathtub with less water so you can be even more sustainable.

How much water does a shower use?

The amount of water you use when taking a shower depends on the flow rate of the water and the time you spend in the shower. On average, a 10-minute shower can use 75-200 liters or 20-53 gallons.

You can use the following table to estimate how much water you use when you shower.

Flow Rate /
Time
7.5 lpm
2 gpm
12.5 lpm
3.3 gpm
20 lpm
5.3 gpm
5 minutes38 l
10 gal
63 l
17 gal
100 l
27 gal
10 minutes75 l
20 gal
125 l
33 gal
200 l
53 gal
15 minutes113 l
30 gal
188 l
50 gal
300 l
80 gal

lpm: liters per minute ; gpm: gallons per minute

You can always cut down on the amount of water you use when you shower. One way I have found to be useful is to set a timer on your phone for 5 minutes and try to finish before it rings. It might seem like 5 minutes is not enough in the beginning but you’ll get used it. All you need to do is get in, shampoo, soap up, and rinse off. If you prefer taking long and relaxing showers, why not consider taking a bath instead?

How can I reduce the flow rate from a faucet?

It is really important to conserve water, and the rate at which it comes out of a faucet can make a big difference to your conservation efforts. It is also important because it can help you save more money. So how can you decrease the flow rate of your faucets? First, make sure that all your faucets are new and have an aerator. If your faucets are new but don’t have aerators, you can buy and install ones easily.

If you are in the US, make sure to buy WaterSense labeled faucets and aerators. WaterSense labels mean the product meets EPA criteria. They have a maximum flow rate of 1.5 gallons per minute and can reduce your water usage by up to 30%. The best part about it is that the savings are passive; all you have to do is install them and make sure they don’t get blocked over time.

What can I do to save water at home?

There is a lot of advice on how to decrease your water usage at home and save water. I have separated them into categories so you can conveniently look at the ones that apply to your household:

Faucets/Taps

  • Turn off the tap while brushing your teeth, shaving, or washing the dishes. This simple action will save you more than 11000 liters or 3000 gallons per year if you only turn it off when brushing your teeth.
  • As mentioned above, replace your faucets with high efficiency ones and make sure to use aerators.

Cooking

  • Only boil the amount of water that you’re gonna use. This also helps save energy.
  • Eat less meat. Beef and poultry products use huge amounts of water. One study estimates that one kg of beef can take 1763 liters of water to produce (Source).

Toilet

  • Use low-flush toilets which can use less than a third of the water used in older toilets. According to the USGS, older toilets can use 15 liters or 4 gallons per flush whereas most new toilets only use 6 liters or 1.6 gallons per flush (Source).
  • Check for a leaky toilet. Put a few drops of food coloring in the toilet tank and check if it shows up in the bowl without flushing.

Shower-heads

  • Use a high-efficiency shower-head. Showers can account for 20% of all water used at home, and high-efficiency shower-head can reduce water usage by up to 70% (Source).
  • Take shorter showers or try to use water more sparingly in your showers. You can set a timer on your phone to keep your showers short.
  • Take baths if you can. Surprisingly, a tub full of water uses less water than the shortest showers.

Washing Machines

  • Only wash your clothes in full loads. Half loads use twice as much water for the same result.
  • Use Energy Star certified washing machines which use 33% less water then other machines (Source).

Dishwashers

  • Dishwashers use less water than washing dishes by hand
  • Try to use dishwashers that are energy and water efficient such as Energy Star certified ones. A dishwasher can save more than 14000 liters or 3870 gallons over its entire lifetime (Source).
  • Similar to washing machines, it is better to use dishwashers with full loads only.

Plumbing

  • Fix your faucets if they are leaky. A leaky faucet can waste up to 15000 liters or 4000 gallons a year (Source).
  • Check your pipes for leaks as well. Leaky pipes are often cited as the number one source of water waste, and leaks outside where it’s closer to the main lines can be especially wasteful.

Gardening

  • Try to water your plants during the cooler times of the day as this will increase the time it takes for the water to evaporate.
  • If you have access to a roof or a balcony, you can install water butts and use rainwater for your plants.
  • Re-use your boiled water from cooking veggies to water your plants. Make sure to let it to cool first.