If a pipe has burst at your house right now, call (858) 333-3038. On bigger Poway lots in Green Valley or Garden Road, the supply line can run a long way from the meter to the house, and the break isn't always close to the front door. The contractor can track down where it is and stop the water.
Most pipes show some sign of trouble before they fail. Pressure drops at one tap, the first water in the morning comes out tinted, a fitting starts to weep, or a patch of yard stays wet when it hasn't rained. That last one matters out here, because a long supply line under the yard can leak for a while before anyone notices.
The contractor can find the break, repair it, and look at the rest of the line too. One bad section gets repaired. A line that's failing in several spots means a conversation about replacing it, laid out in plain English with the tradeoffs, and it's your call.