If your water bill goes up, but you haven't changed the way you use water, chances are you have a leak. Leaks can waste several or even hundreds of gallons of water per day, so it's good to check for leaks at least once or twice each year.

Detecting a home water leak

Step 1: Locate your water meter

  • Residential water meters are usually located near the curb or sidewalk in a concrete box.
  • Use a screwdriver to lift the meter box lid to access the meter.

Step 2: Ensure no water is being used on your property

  • Turn off all indoor and outdoor water using appliances (sinks, showers, garden hose, etc.)

Step 3: Check your water meter

  • Locate the leak detector triangle, or asterisk (see arrow pointing to this in the image below). If you observe any type of movement on the Leak detector, you have a leak on your property.

Learn more information about reading your water meter at the Reading your water meter page.

Finding out if your leak is indoors or outdoors

You’ve checked your water meter and confirmed there’s a leak – now let’s narrow down where it is. 

Step 1: Shut off your house valve

  • Your house valve is usually located where the main water line enters your home. Find it and turn it off.  

  • If your house does not have a shut-off valve, call your water retailer so that a water technician can be sent to turn off the water for you. Look up your water retailer.

Step 2: Check your water meter

  • Watch the flow indicator on the meter for a few minutes.
    • If the indicator moves, the leak is outside—likely in the irrigation system or the service line between the meter and the house.
    • If the indicator stays still, the leak is inside the home, possibly from a toilet, faucet, water softener, or another appliance.  

Step 3: Find the leak

Once you’ve identified whether the leak is indoors or outdoors, try narrowing it down:

  • Outdoors:
    • Start with the irrigation system. Check irrigation valves as they are prone to getting stuck open and faucet spigots for your hoses.
    • If not irrigation-related, inspect the service line for wet or muddy spots between the meter and house.
    • If no visible signs, you may need to have a professional plumber assist you in pinpointing the leak.
  • Indoors:
    • Check toilet tanks first. Use a dye test to detect silent, rubber flapper leaks.
      • Place dye in the tank, wait five minutes. If the dye enters the bowl, you have a flapper leak.
    • If the leak is indoors and it is not a toilet leak, check all other water-using fixtures and appliances.

Step 4: Fix the leak

  • Some leaks are easy to fix like replacing a toilet flapper or cleaning a stuck irrigation valve. 
  • More complex issues, such as service line leaks, may require a plumber or professional repair. 

Water Wise Programs

Valley Water Free Water Saving Devices

To request water saving items, call the Santa Clara Valley Water District's water conservation hotline at (408) 630-2554 or go to the Valley Water Shopping Cart to get items shipped to you for free. Santa Clara County residents can request a do-it-yourself items to evaluate indoor water use, including dye tablets to test toilets for leaks. You can also call (408) 630-2554 to schedule an inspection.

For Customers of San Jose Water Company

Learn more about the Water Audit Program or call: (408) 279-7900.