How a Leaky Toilet Affects the Water Bill

Is Your Throne Fit for a King, or Fit for a Repair?

What Causes a Toilet Leak?

  • The flapper becomes warped or damaged and does not provide a watertight seal on the flush valve. In-tank toilet cleaners can cause flapper damage.
  • The flapper, trip lever or chain may lose its alignment with the flush valve, leaving a gap that can cause a leak.
  • The flush valve can develop small cuts or other damage that causes a leak between it and the flapper.  This is usually caused by grit or sediment.
  •  The fill valve can become stuck in an open position causing water waste as it flows down the overflow tube.  This can happen when your water pressure changes in your home.

How Can I Test for Toilet Leaks?

  • Listen - The toilet should make a refill noise only when the tank is refilling after a flush.  
  • Look - A large leak will cause moving water in the bowl long after the tank has refilled from a flush.  For a small leak, place some food coloring in the tank.  If the color appears in the bowl you have a leak.

High water bills are often caused by leaking toilets that waste large amounts of water

Size of Leak
Amount of Water Waste Per Day
Small 30 gallons per day
Medium 250 gallons per day
Large Up to 4,000 gallons per day

Running toilets use even more!

How to Detect Leaks

Leaking faucets are generally a result of a worn rubber washer.  The washer on a sink is usually located under the handle.  These are relatively easy to replace if you have the right tools.  It does require shutting off the water under the sink or at the main shutoff valve and removing the handle.  (NOTE: faucet handles are NOT shutoff valves.)  Check your local home center or hardware store on how to repair faucet leaks.