Tracking Down a Hidden Leak

Start at the meter

With every tap, appliance and sprinkler off, look at the meter's leak indicator. Movement means water is flowing somewhere.

Split the house from the yard

Close the main valve at the house. If the indicator stops, the leak is inside. If it keeps turning, look at the line between the meter and the house, or at outdoor lines.

Toilets are common culprits

A worn flapper lets water trickle into the bowl silently. Add food coloring to each tank and wait 15 minutes; color in the bowl means a leak.

Look and listen

Check under sinks, behind the washer, around the water heater and in the basement or crawl space. Listen at walls near bathrooms for hissing.

After winter

In spring, hose bibs and sprinkler lines damaged by frost are frequent sources. Run each one and look inside the wall behind it.

Get help

If you can't find it, a plumber can trace it with testing equipment. See emergency plumbing if water is visible.

Overnight reading

If the indicator is hard to see, write down the meter reading at bedtime and again first thing in the morning, using no water in between. Any change means water moved while the house was quiet.

Water softeners and heaters

A water softener stuck in its rinse cycle or a dripping relief valve on the water heater can send water down a drain without anyone noticing. Check both before assuming the leak is inside a wall.

More plumbing guides

• A Snow-Season Plumbing Checklist for Ogden Homes
• Shutting Off Your Water in an Emergency
• When to Replace a Water Heater
• Sprinkler and Hose Bib Shut-Down
• Checking a Utah Plumber Before You Hire