How to find a hidden water leak with your water meter

How do you check for a leak with your water meter?

Use a time when nobody needs water for a couple of hours. Then:

1. Turn off every tap, and make sure nothing that uses water is running: the dishwasher, the washing machine, the irrigation system, an ice maker or a humidifier.
2. Find your meter and write down the reading. Many meters also have a small leak indicator, a dial or symbol that turns whenever any water is moving through.
3. Watch the indicator for a few minutes. If it turns with everything off, water is going somewhere.
4. For a slow leak, leave everything off for two hours and read the meter again. Any change means a leak.

The City of Surrey has short videos that show how to find and read the meter and check for a leak this way.

Where is the water meter?

In Surrey, meters are required for all new homes, including single family houses, and the City has a page on understanding your water meter with help on finding it. A meter is often in a box in the ground near the front property line, or where the water line comes into the house. Vancouver is bringing in metering across the city, so more homes there will have one too.

If your home has no meter, you can still look and listen for the signs further down this guide.

Which leaks are most common inside the house?

Start with the toilets. Surrey lists toilets, pipes, taps, hot water tanks and irrigation systems as the usual places, and says leaking toilets are usually high volume and hard to spot. Check in this order:

• Toilets. Listen for running water when nobody has flushed. If it’s quiet, put a few drops of food colouring in the tank and wait 15 minutes without flushing. Colour in the bowl means the flapper is leaking. Our guide on a toilet that keeps running covers the fixes.
• Taps and the pipes under sinks. Look for drips and damp cabinet floors.
• The hot water tank. Look for water around the base or coming from the overflow tube. Our guide on a leaking water heater explains what each kind of leak means.
• Outdoor taps and irrigation. Check for wet patches in the lawn that never dry and for drips at hose connections.

How do you tell if the leak is in the buried line outside?

Close the main shut-off where the water line comes into the house, then watch the meter again. If it still moves with the main closed, the water is escaping between the meter and the house, which is usually the buried service line. If it stops, the leak is somewhere in the house plumbing.

Other signs of a buried line leak are a wet patch in the yard, pressure that has dropped at every tap, and water seeping in where the line enters the basement. Our guide on who owns the water line covers which part the city looks after, and when a line is worth replacing.

What are the signs of a leak in a wall or under the floor?

A leak inside the walls or under a concrete floor can run for weeks before you see water. Look for:

• A stain on a ceiling or wall that keeps getting bigger.
• Paint bubbling, or drywall going soft near a bathroom or kitchen.
• A musty smell, or mould in a corner that stays damp.
• A warm spot on a floor, which can mean a hot water line leaking under it.
• The sound of water running inside a wall when everything is off.

Water often runs along a pipe or a joist before it drips through, so the stain may not be right under the leak. Finding where it starts is the hard part of the job.

How much water can a hidden leak waste?

More than most people expect. Surrey’s figures put a dripping tap at about 57 litres a day, and a 0.8 mm hole in a pipe, about what a leaking toilet loses, at roughly 1,000 litres a day. On a metered home that water is on your bill.

In Surrey, if a leak on your property pushed your bill up, you can apply for a leak adjustment once it’s fixed. Read the meter to show your use is back to normal, and send the City’s form with your repair receipts.

Will the city find or fix the leak for you?

Not on your property. Surrey says it is not responsible for detecting or fixing water leaks on private property. Vancouver repairs leaks only on the City’s part of the line, and bills the owner for a service visit when the cause turns out to be on private property.

When to call a plumber

Call a plumber when:

• The meter moves with everything off and the toilets check out.
• The meter still moves after you close the main shut-off.
• A stain is spreading, or a floor feels warm in one spot.
• You hear water running in a wall when nothing is on.
• Your water bill has jumped and you can’t find the reason.

DrainX traces leaks back to where they start, inside the house and in the buried water service line, then repairs the pipe or fitting and shows you what we found. Tell us what the meter did with the main shut-off open and closed, and where you’ve seen water.