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How to Detect a Leak

General Detection of Leaks within Your Home

By detecting a leak in its early stages, an individual could save a substantial amount of money. Water leaks (either a large leak or a combination of smaller leaks) can often be detected through a test using your water meter.  

Using your water meter, the following steps will allow you to perform a simple leak check:

  1. Ensure that you have turned off all water both inside and outside of the house.
  2. Make sure that all automatic water equipment (clothes washers, dishwashers, sprinkler systems, irrigation controllers, etc.) are not running at this time.
  3. Take a reading of your water meter and record that reading. 
  4. Wait 15 minutes before reading your meter again and recording that reading.
  5. If your meter has recorded water use during this 15 minute period, it could be due to a leak.

Note: If you did record use during this period, you may want to confirm that the water use is not due to small appliances such as water filters, water softeners, or whole house humidifiers.

Once you have confirmed that there is a leak, you will need to take other measures to determine the location of the leak(s).

Water Supply Line Leaks
There are sometimes leaks between the meter and the home, in the water supply line.  Start by examining your yard between the meter and house during dry weather for signs of a soft or muddy spot or a patch of greener grass. These leaks are often difficult to detect because the supply pipe is usually buried at least 3 feet (.91 m) below the ground surface.

Sometimes the leaking water will travel along the pipe, back to the meter. If the meter box contains water, and the water is not due to rain or irrigation run-off, this may indicate a leak in the supply line. Another common exit point for the leaking water might be where the supply line rises above the ground and/or enters the house.  

Typically, leaks between the meter and the house are the responsibility of the homeowner; leaks from the meter or pipes leading from the main to the meter are the responsibility of the water utility. The water utility should be contacted before any attempt to repair the water supply pipe. If the utility deems the leak to be the responsibility of the homeowner, a professional plumber should be contacted.


Faucet, Shower, and Tub Leaks
Replace worn washers in faucets and showerheads. Even a small drip can waste as much as 170 gallons of water each day.

Faucet leaks are a common occurrence and usually simple to repair.  A faucet dripping slowly at only one drop every two seconds will waste more than 1,000 gallons (3.7 m3) per year.   The repairs necessary to stop the leak depends on the type of faucet. If you are comfortable with making minor home repairs you should be able to repair most minor faucet leaks, otherwise, contact a professional plumber.

Toilet Leaks

Toilets are one the most common sources of leaks in the home, and usually go unnoticed because the leaks are often silent. 


Note:  Large toilet leaks can be detected when the valve constantly emits a hissing or gurgling sound when the toilet is not in use. 


To begin looking for leaks, remove the tank lid and inspect the flush mechanisms. The water level in the tank should be no higher than 1 inch below the top of the overflow tube.  If the water level is to the very top of the overflow tube, water is slowly leaking into the overflow tube and down the drain.  

Follow these simple steps to diagnose a leaky toilet:

  1. If you use an automatic bowl cleaning device, remove it.  Do not continue until all coloring from the automatic bowl cleaning device is gone.
  2. At least five minutes after the last flush cycle, carefully remove the toilet tank cover.
  3. Gently add 4 to 5 drops of blue, green, or red food coloring into the tank (not the bowl). DO NOT FLUSH. Test dye tablets are available at the office of North Beach Water District.
  4. Wait 10 to 15 minutes – no flushing during this time. If you find color in the bowl, there’s a leak.

Common causes of toilet leaks include:

  • The flapper valve or valve seat has deteriorated
  • The flushing arm or lift chain is not working properly
  • The tank water level is too high and spills into the overflow
  • The float rod, ballcock, or float ball may be worn or corroded

Leaks in toilets always get larger and more costly over time. The sooner repairs are made the more quickly you can start saving water – and money.

Once repairs are completed take a few minutes to re-test, to assure there are no more leaks.