Finding a hidden water leak

Leaks that you cannot see can cost the most, because they can run for months. The goal is to learn whether water is leaking at all, then which side of the meter, then which pipe.

Step one: confirm there is a leak

Turn off every tap and appliance, then look at the meter. If the low flow indicator or the dial moves, water is passing through the meter, which points to a leak after it, on the house side. If it stands still, the leak may be intermittent, before the meter or absent, and the bill rise may have come from use. Your meter belongs to the water supplier, but you can read it.

Step two: check the usual suspects

Toilets are the easiest place to test. OCWA's own method is to lift the tank lid, add a few drops of food coloring and wait about 45 minutes. If color reaches the bowl without flushing, the flapper may need replacing. Next look at faucets, hose bibs, the water heater's relief pipe and any softener or humidifier.

Step three: before or after the shutoff

Keep every fixture off and watch the dial. If it keeps moving, water is passing through the meter, so the leak is after it, inside the house. Where the meter sits just inside the cellar wall, as OCWA's rules allow for services of 150 feet or less, the buried line comes before it, and a leak there will not move the dial. Its signs are soft or unusually green ground, a wet spot at the foundation, low pressure or a notice from the supplier, and a contractor confirms it with pressure or acoustic tests. A meter in a curb pit is the exception, so ask the supplier where yours sits. In the City of Syracuse your responsibility begins at the curb box. Outside the city, OCWA describes your side as starting at the valve at the property line, though its FAQ puts all piping with the owner, so ask it where your boundary is. The meter itself is not yours.

Where leaks hide

• Under a slab or in a basement floor, where hot lines can warm the surface above them.
• Inside walls near fixtures, shown by stained plaster or peeling paint.
• Buried between the curb and the house, shown by soft or unusually green ground.
• Behind tub and shower valves.
• Pipes that sweat in humid summers. The average July dew point at Syracuse airport is about 61 degrees Fahrenheit, so a cold water pipe cooler than that collects condensation that can look like a leak and drip like one.

How contractors trace a leak

Pressure testing isolates each branch. Acoustic listening picks up the sound of escaping water. Thermal imaging shows warm or cool patches. Tracer gas or metal locators help on buried lines. The point of all of them is a small opening instead of a torn out wall. A good contractor will show you the spot before cutting.

What winter leaves behind

Freezing can split a pipe that shows no sign until the thaw. If your house went through a hard cold snap and the bill rose afterwards, ask for a leak search. The damage found may include a split pipe or a cracked fitting.

Why it matters to repair quickly

OCWA's rules list wasting water through a customer's unrepaired leaking pipes among the grounds to discontinue service. More practically, leaks rot framing, grow mold and run up the bill. Syracuse also bases its sewer charge on actual water use, so wasted water costs twice.

Small steps while you wait

Before you call anyone, photograph the meter face, the area under each sink and the base of the water heater. Dated pictures help a contractor judge how fast water is escaping. If a spot is wet, wipe it dry and check again in a few hours so you know whether it is active.

Keep a record

Write down the meter reading and the date before and after the repair. A week later, repeat the test with everything off. If the dial still creeps, a second leak may be present. That small log is the evidence that the job worked.

Repair afterwards

Once located, the repair can be a fitting, a pipe section or a valve. Disinfection is required before use on altered or repaired potable lines under the county requirements. Ask whether it is included. Get the price for the repair separately from the search, so you can compare.

Source Onondaga County Water Authority and City of Syracuse Department of Water, read Oct 5, 2026.