How to Find a Hidden Leak

A bill that jumps with no change in habits is often the first clue. Compare the same month from last year to rule out seasonal use like irrigation or a pool.

Turn off every faucet, appliance, irrigation valve and pool fill. Lift the City meter lid near the sidewalk and watch the small leak indicator for a few minutes. If it moves, water is going somewhere.

Close the main valve at the house and watch again. If the indicator stops, the leak is inside. If it keeps moving, the leak is between the meter and the house, often in the yard line, which can be long on large North Central lots.

Look for bubbling paint, soft plaster, swollen baseboards, cupped wood floors, dark grout lines and stains. Feel for cool or damp spots. Smell for must in closets and bathrooms.

Open sink cabinets and look for drips, stains and soft bottoms. Pull the washer and refrigerator out a little and check the wall and floor behind them.

Put a few drops of food coloring in the tank and wait 15 minutes without flushing. Color in the bowl means the flapper is leaking.

In homes with galvanized pipes, brown water and low pressure suggest pipes near failure. Small leaks at threaded fittings often show as orange crust under sinks.

Call a plumber for leak detection if the meter moves and you cannot find the source. If walls or floors are already wet, call for drying too; see drying and dehumidification.

Do a meter test once or twice a year and look under sinks every few months.

On large North Central lots, the line from the meter to the house can be long and old. A leak there may not show as a wet spot if the soil drains well. If the meter keeps moving with the house valve closed, a plumber can locate the yard leak with listening equipment.

Irrigation valves that do not close fully, broken drip lines and pool auto-fill valves are common hidden water users. Turn them off during the meter test to rule them out, then test each one.

Plaster walls show leaks differently than drywall. Look for hairline cracks that appear suddenly, paint that bubbles or flakes and areas that feel cool. Tap gently; damp plaster can sound different.

Look at ceilings below bathrooms, near the water heater closet and under flat roofs. A faint ring or a change in texture may be the first sign of a slow leak.

Found a damp wall or a moving meter? Call (602) 878-3892 for a local provider who can check moisture and start drying.

Check the water heater's relief valve pipe for drips and the base for rust or water. If you have a softener, check its fittings and brine tank. These are easy to overlook.

Write down meter readings and dates. A log shows whether a leak is new and helps a plumber narrow it down.

Pinholes in galvanized pipe inside walls, slow drips at old shut-off valves under sinks, toilet flappers, leaking tub spouts and yard lines on large lots are the usual suspects in North Central Phoenix homes.

The meter never lies. Test it twice a year.

Hidden leaks in older homes usually give small signs before they cause big damage: a higher bill, a moving meter, a soft patch of plaster, a musty closet. Paying attention to those signs, and calling a plumber when the meter moves, keeps a small leak from becoming a large repair.

Set a reminder twice a year to compare water bills, do the meter test, open every sink cabinet and walk the house looking at walls, floors and ceilings. Ten minutes of checking can catch a leak months before it shows up as a stain.

If the meter moves and you cannot find the source, call a plumber for leak detection, and call (602) 878-3892 if walls or floors are already damp. Early action keeps repairs small. Check it twice every year.

Watch the bill, test the meter, check walls and cabinets, and call for help when the meter moves or a wall feels damp.

Questions about how to find a hidden leak? Call (602) 878-3892 to reach a local North Central Phoenix provider, 24 hours a day.