If you suspect that water may be leaking from a broken pipe or fitting somewhere underground, here's how to know for sure:

1) Turn off every faucet, fixture, and appliance that uses water'even the ice maker.

2) Open the water meter's cover so that you can see the gauge.

3) Mark the rim of the gauge where the needle is pointing (if there are several dials, mark the one that indicates 1-cubic-foot increments).

4) Leave the water shut off for 30 minutes, and then see if the needle has moved from the mark. If it has, your plumbing is leaking somewhere.

5) You can look for signs of a leak, such as sink holes or mushy areas of ground, but you may have to have a professional find it.