Hidden water loss detection in Arizona: water is leaving and you can't see where
Most leak calls in the Valley don't begin with a puddle. They begin with a number. The monthly bill is higher than it should be, or someone lifted the meter lid and saw the indicator turning while the house was quiet. Nothing is wet, nothing sounds wrong, and the question is simply where the water is ending up.
A slab leak is one answer. It is rarely the only possible one, and treating it as the first guess can mean paying for detection work that a few minutes at the meter would have ruled out.
What people notice first
Why Arizona homes make this harder
A typical Valley lot has more places for water to go than a house in most other states. Pools with automatic fill valves top themselves up without anyone noticing. Drip systems run on timers before dawn, with dozens of emitters and buried tubing that can split or pull loose. The service line from the street meter often runs a long way under gravel and pavers before it reaches the foundation. Some homes still have an evaporative cooler with its own feed, and many have a softener or filter system that sends water to a drain on a schedule.
Each of those can raise a bill or move the meter the same way a leak under the slab does. That's why we treat elimination as the first job on every call. It's quicker for you, and it means that when a technician does start listening at the floor, they already know the house is the likely source.
Checks you can make before you call
Three observations, no tools. Stop at whichever step answers the question.
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1
Everything off, watch the meter
Close every tap, make sure the dishwasher and washer are idle and no toilet is refilling. Lift the meter lid and watch the small leak indicator for five minutes or so.
Still: no constant leak right now. Turning: go to step 2.
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2
Irrigation controller to off
Switch the controller off at its panel. Don't open valve boxes or dig. Wait a few minutes and watch the indicator again.
Stops: the drip system or its feed is the likely source; a landscape contractor handles that. Still turning: go to step 3.
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3
Note the pool level overnight
If you have a pool, note where the water sits against a tile line in the morning and look again the next morning. In summer some drop is normal evaporation, so just tell us what you saw.
Dropping noticeably: mention it; pool repair is a separate trade. Steady: go to step 4.
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4
Likely the service line or the slab
With the house quiet, the irrigation off and the pool steady, a moving meter points at the line from the meter to the house or a line under the floor. This is where the technician comes in.
Meter Still Moving? Talk to a Leak Tech
Coolers, softeners and filter systems are harder to rule out on your own. Mention them on the call; the technician isolates them as part of locating. See the hidden water uses checklist.
How the technician narrows it down
The technician picks up where your checks left off. The first aim is to separate the yard from the house: the service line is isolated and tested so that a leak between the meter and the foundation isn't mistaken for one under the floor. Inside, hot, cold and any outdoor branches are isolated in turn.
Once one line is shown to be losing pressure, acoustic equipment is used to listen for escaping water through the slab, and thermal imaging helps trace a hot line that is spreading heat. The likely spot is marked, and you'll hear plainly how confident the technician is. More on how slab leaks are found.
Writing down what you saw
A few notes make the first visit shorter. Write down the time of each meter reading, whether the leak indicator was moving, and how quickly. A slow creep and a steady spin point to leaks of different sizes, though neither says where the water is going.
Also note anything that changed around the time the bill rose: a new pool cover, a different watering schedule, a house full of guests, a new appliance. These are explanations a technician will want to rule in or out before anyone opens a floor. Photograph the meter face, including the register digits, and take the same photo the next morning. Two readings a few hours apart give a clearer picture than one.
If you can't reach the meter, or the box is full of water or debris, leave it alone and tell the dispatcher. Meter boxes can shelter insects and small animals, so lift the lid with a tool rather than your fingers.
If it is under the slab
The contractor sets out pricing once the leak is located.
Afterwards
When the repair is done, the line is tested again and the meter should sit still with the house quiet. Run the same check yourself a few days later; it's the simplest confirmation there is. Any floor or wall patching, drying or cleanup is a separate job, and the technician can tell you what to look for in someone to handle it. What to expect after a slab leak repair.
Questions about hidden water loss
How long should I watch the meter?
Five minutes is usually enough for the leak indicator. If you want a second read, note the main dial before bed and again in the morning with nothing used overnight.
The meter only moves sometimes. Is that a leak?
It may be a fixture that runs intermittently, such as a toilet refilling, a softener regenerating or a pool auto-fill. A slab leak tends to move the meter steadily. Mention the pattern on the call.
I can't find my meter box. What now?
It's usually near the street or sidewalk in front of the house, under a lid flush with the ground. If gravel or landscaping has covered it, skip the check and call; the technician will find it.
Could the leak be in the yard instead of under the house?
Yes, and on longer Valley lots it's common. That's why the service line is tested separately before anyone listens at the slab. See yard lines vs slab leaks.
Should I turn the pool's auto-fill off to test?
We don't ask homeowners to adjust pool equipment. Watching the waterline is enough for a first read, and the technician can isolate the fill line during the visit if needed.
What if every check comes back clean?
Then a constant leak is unlikely right now. A high bill may come from use patterns or an intermittent fixture. If you still notice warm floor or running sounds, call anyway; those point at the house regardless of the meter.
Do the contractors fix drip systems or pools if that's the cause?
No. We handle slab leaks only. If the checks point to the pool or irrigation, you'll know before anyone is sent out, and that work belongs with those trades.
Is there anything I shouldn't do while I wait?
Don't dig, break flooring or open plumbing to look for the leak. Keep clear of water near outlets, appliances or pool equipment. If you smell gas, leave the house and call the gas utility and emergency services from outside.