A water bill that jumps when nothing at home has changed is one of the most common first signs of a hidden leak. Before you assume the worst, though, it’s worth ruling out the simple causes and checking the meter yourself.
Start with the simple causes
- A running toilet. A flapper that doesn’t seal can let water run quietly all day. Check every toilet for refilling when nobody has flushed.
- Irrigation. A changed timer, a stuck valve or a broken sprinkler head can use a lot of water without anyone noticing.
- A pool auto-fill. If it’s running constantly, the pool may be losing water.
How to check your water meter for a leak
You don’t need tools for this, just a quiet house.
- Turn off every tap and water-using appliance, including the sprinklers.
- Make sure no toilet is refilling.
- Find your meter, usually in a concrete box near the street or sidewalk.
- Note the reading on your meter.
- Use no water for about an hour, then check it again.
If the number moved, water is going somewhere. It could be a running toilet, so check those first. If the toilets are quiet, a hidden leak is likely. Your water provider may also be able to help you read the meter.
Is it the house or the yard?
A typical property holds more than one pressurized system. To split the yard from the house, run the meter test twice:
- With the irrigation shut at its main valve or backflow device, not just the timer.
- With that valve open again and the timer still off.
If the meter only moves on the second run, the leak is likely on the irrigation side. If it moves both times, the main line or something inside the house is the better suspect.
Your side of the meter or the utility’s?
In general, the line from the meter to your house belongs to the property owner, and the street side usually belongs to the water utility. Boundaries vary by provider, so if water is bubbling up at the curb or in the street, call your water provider first.
What a moving meter does and doesn’t tell you
A moving meter only confirms that something is leaking. It doesn’t tell you where. Finding where, whether it’s a wall, a slab, a yard line or a pool, is the part that takes testing.
Meter moving with everything off? See residential, slab and underground leak detection, or request service.
