Isolating the water
Shutting the house down at the main or at a branch valve, so the rest of the property can stay usable while the repair is planned.
A pressurized line that has opened up puts out water fast, and every minute it runs is more drywall, flooring and baseboard. Tempe Emergency Plumber gets the water stopped, finds the break and repairs the line, then tells you why that section failed.
Close the main valve first. In most Arizona homes it is on the supply line where it enters the house at the front, often beside a hose bib, or in the garage near the water softener loop. There is also a valve in the meter box near the street, which needs a meter key. Do not stand in spreading water near outlets, and do not try to clamp or tape a line that is still under pressure.

The order matters on a burst line: stop the water, find the break, then repair the pipe properly rather than patching whatever is easiest to reach.
Shutting the house down at the main or at a branch valve, so the rest of the property can stay usable while the repair is planned.
Pressure testing and listening equipment narrow it down when the pipe is inside a wall, above a ceiling or under the slab, so the opening is as small as the job allows.
Cutting out the failed section and repairing it, or replacing the whole run where the material itself is the problem. You are told which situation you are in.
The line is brought back up to pressure and checked before anyone leaves, and you are shown the failed piece of pipe so you can see what went wrong.
Hard water does most of the long-term damage. Mineral-heavy water moving through copper for decades thins the pipe from the inside, and pinholes turn up first on the hot side, where heat speeds the process along. Older homes near campus and through central Tempe are far enough into that timeline for the first failures to be arriving now.
Polybutylene is the other common culprit. Plenty of valley homes built between the early 1980s and the middle 1990s were plumbed with gray polybutylene tubing and plastic fittings that go brittle with time and treated water. When those let go, they usually do it at a fitting, without warning, and the whole run is suspect rather than that one joint. Beyond that we see damaged lines from a nail or a screw hitting pipe during a remodel, and exposed runs in unconditioned space that have baked through too many summers.
If the water is still spreading, read what to do when a pipe bursts while you wait. If you cannot see where it is coming from, start with leak detection. A line under the concrete is covered on our slab leak repair page, and when a leaking water heater is the source, our repair or replacement comparison explains the decision. You can also request service directly.
It follows the repair, not a list price. What drives it is where the break is, how much drywall, tile or concrete has to come out to reach it, and whether the rest of that run is sound. Tempe Emergency Plumber finds the break first, then gives you a price before any cutting starts, so nothing gets approved sight unseen.
Look for a valve on the supply line where it enters the house at the front, often near a hose bib, or in the garage close to the water softener loop. Turn it clockwise. If there is no valve or it will not budge, the meter box near the street has one, though it needs a meter key. Find yours now rather than during an emergency.
That is a question for your policy and your carrier, and every policy is different. What helps either way is documentation: photograph the water and the damaged area before cleanup starts, and keep the failed section of pipe. Tempe Emergency Plumber can show you what failed so you can describe it accurately.
It depends on the material. A single failure in otherwise sound copper is usually a spot repair. Repeat pinholes in the same run, or any failure in polybutylene, point toward replacing the run, because the next one is coming. See the same thinking applied to water heaters on our comparison page.
Call and describe what you can see. We will talk you through the shutoff while a plumber is dispatched.