Leak detection finds water escaping from hidden pipes in walls, under a concrete slab or in the yard line, using meter checks, pressure tests, acoustic listening gear and thermal cameras before anything is opened up. Pinpointing the spot keeps the repair small. Call the number on this page to be connected with a local plumber in Phoenix.

Warning signs
- A water bill that climbs while your habits stay the same
- The meter's leak indicator spinning with everything shut off
- A warm or damp patch on a tile or concrete floor
- Stained drywall, swollen baseboards or lifting flooring
- Running water sounds when no fixture is on
- A wet or extra-green spot in the yard along the water line
Try this first
Shut off all faucets, appliances and irrigation, then check the meter. If the indicator still moves, something is leaking. Toilets are a frequent cause, so put a little food coloring in each tank and wait; color in the bowl without a flush means a flapper is letting water through. Also check irrigation valves and pool auto-fill lines, which are common outdoor leak points.
Slab homes and hidden lines
Phoenix houses are commonly built slab-on-grade, with water lines running under or through the concrete. A leak there may show up only as a warm floor, a higher bill or a meter that will not stop. Hard Phoenix water, which the City lists at 10 to 17.6 grains per gallon, leaves scale in fixtures and appliances, and older central neighborhoods can still have galvanized supply pipe that corrodes from the inside.
How a plumber narrows it down
| Technique | Purpose |
|---|---|
| Isolation testing | Close valves section by section to find which part of the system is losing water |
| Pressure test | Confirms whether a line holds pressure |
| Acoustic detection | Listens through floors and soil for the sound of escaping water |
| Thermal imaging | Spots warm hot-water leaks and cool wet areas behind surfaces |
| Moisture meter | Maps how far water has traveled into walls and flooring |
The yard line belongs to you
The City of Phoenix says property owners are responsible for the water line on their property up to the City main, so a leak on that line is usually a plumber job for the owner. If water is gushing from the street, a hydrant or a broken main, report it to the City at 602-261-8000.
What affects cost
Price depends on how many methods are needed, how much piping must be ruled out, access, and whether the leak is indoors, under the slab or outside. The repair is quoted separately once the leak is found.
Leak Detection questions from Phoenix homeowners
How can I tell if I have a hidden leak in Phoenix?
Who fixes a leak on the water line in my yard?
Can a slab leak be found without breaking up the floor?
Who do I call about water gushing from the street?
Related plumbing services in Phoenix
Leak Detection in nearby cities and towns
Maricopa County
Pinal County
Sources
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