How Much Water Fixtures Use

How much do your water fixtures use and how does it compare to a WaterSense certified product?


WaterSense certified showerheads are required to flow at a rate of 2.0 gallons per minute (gpm) or less.  Since 1994, national standards require showerheads to use 2.5 gpm or less.  Prior to that, showerheads were manufactured to use anywhere from 3.0 gpm to 5 gpm.

Showerhead gpm arrowLook closely at your showerhead – gpm is often printed on the face of the showerhead or around the showerhead base.  If the gpm is not visible, place a bucket with gallon increments marked under the showerhead and time how many seconds it takes to fill the bucket to the 1 gallon mark. Use this equation: 


60 seconds / # of seconds recorded x 1 gallon = ?? gallons/minute.


WaterSense certified toilets are guaranteed to use 1.28 gallons per flush (gpf) or lessSince 1994, national standards required only toilets using no more than 1.6 gallons per flush (gpf) be sold.  Pre-1994 residential toilets used between 3.5 gpf to 10 gpf.

Most toilets have the gpf stamped between the hinges on the toilet seat and the toilet tank.  Put the toilet seat down to see if it is printed there.  If not, lift the cover off the toilet tank and look for a date stamp on the underside of the lid or on the side of the tank.  Toilets dated prior to January 1, 1980 likely use between  5 gpf and 7 gpf.  Toilets dated between January 1, 1980 and January 1 , 1994 likely use 3.5 gpf and toilets dated after January 1, 1994 use 1.6 gpf.  If you see the letters “ULF” printed, this means the toilet is ultra low flow and uses 1.6 gpf.

Sink Faucet

WaterSense certified faucets and sink aerators are tested to perform at 1.5 gallons per minute or less.  Since 1994, faucet standards have been between 2.2 gpm and 2.5 gpm.

Tri-max aerator 1.5Aerators are the nozzles with a screen on them that the water flows out of on your sink faucet.  To determine how much water is flowing out of your sink, look closely at the side of the aerator for the printed gpm. If the gpm is not visible, use the method for measuring flow described above in the shower section.

Clothes Washer

The WaterSense program does not yet certify washing machines, but the EPA Energy Star program does.  Washing machines save energy by using less hot water.  Washing machines manufactured  before 2010 are the least efficient energy and water wise.  For more information about Energy Star, go to the Energy Star website.