Leak Detection Across the Bay Area — Find It Before You Dig
A leak you cannot see is still doing damage. We locate slab leaks, buried service line leaks and concealed pipe leaks using acoustic listening, thermal imaging and pressure testing. The aim is to pinpoint the leak precisely, so the repair opens up as little floor, wall or ground as possible.
Already know where it is? See leak detection and repair for the fix itself.
- Slab leaks under concrete floors and foundations
- Buried leaks on the service line between meter and house
- Concealed leaks in walls, ceilings and crawl spaces
- Meter testing to confirm whether you are losing water at all
- Pressure and isolation testing to narrow down the zone
- Acoustic listening and thermal imaging to pinpoint the spot
- A clear report and marked location before any repair
Signs You Have a Hidden Leak
Catching these early is almost always cheaper than waiting for the failure.
The meter moves with everything off
Shut every tap and appliance, then watch the low-flow indicator on the meter. If it creeps, water is going somewhere. This is the cheapest test there is, and it tells us straight away whether we are hunting a live leak or chasing an old stain.
A warm patch on the floor
A warm or hot area on a slab floor almost always means a leak on the hot side of the under-slab pipework. You may also hear water running with nothing switched on. Left alone, it will undermine the slab and drive up the heating cost of every hot tap.
Water bill climbing for no reason
A steady rise in usage with no change in habits is the classic buried leak. On a service line between the meter and the house, the water often never surfaces at all — it simply soaks away into the ground, which is why nothing looks wrong above.
Damp patches or a musty smell
Staining on a ceiling or the base of a wall, blistered paint, lifting flooring or a persistent musty smell all point to water arriving somewhere it should not. The visible mark is often well away from the actual leak, which is why pinpointing matters.
Pressure has dropped off
A noticeable fall in pressure across the whole house can mean a substantial leak upstream, though it can also be a failing pressure regulator or corroded galvanised pipe narrowing the bore. Testing tells you which, before anyone starts breaking concrete.
A wet spot in the garden or drive
Grass that stays green in a dry spell, a soft patch of lawn, or water seeping at the edge of a driveway usually marks a buried supply leak. It rarely surfaces directly above the fault, so digging where it looks wet is often digging in the wrong place.
The Kinds of Leak We Track Down
Slab leaks
Pipework run under or within a concrete slab, leaking where you cannot see it. Expansive clay soil across much of the Bay Area moves with the seasons, and that movement stresses pipe and joints under the slab. We locate the point acoustically and confirm with thermal imaging before anything is cut.
Buried service line leaks
The run between the water meter and the house is usually the longest unbroken length of pipe on the property, and often the oldest. We isolate it from the house, pressure test it, then trace and listen along the route so the excavation lands on the fault rather than near it.
Concealed leaks in walls and ceilings
Water travels along joists and behind finishes, so the damp patch is rarely above the leak. Thermal imaging shows the temperature pattern behind the surface and moisture meters map how far it has spread, which narrows the opening to something you can patch easily.
Drain and waste leaks
Waste pipes are not under pressure, so listening equipment has little to work with. These are found differently: camera inspection inside the line, plus dye and fill testing to prove which fixture or section is losing water. Different tools, same goal of pinpointing before opening up.
How We Find a Leak
Meter test first
We shut everything down and read the meter, which confirms whether water is actually being lost and gives a rough sense of the rate. It takes minutes and it stops the whole job going down the wrong path from the start.
Isolate and pressure test
By closing valves in sequence and pressure testing sections, we separate the house from the service line and irrigation from everything else. That tells us which part of the system is losing pressure, so the search area shrinks from a whole property to one run of pipe.
Pinpoint with acoustic and thermal
Pressurised leaks make noise. Acoustic equipment picks that up through slab, soil and finishes, and thermal imaging shows temperature differences where water is tracking. Between them we can mark the location tightly rather than giving you a general area.
Confirm and mark the spot
We cross-check the location by more than one method wherever we can, then mark it clearly on the floor, wall or ground. If a drain is involved we run a camera to confirm what is happening inside the line before anyone excavates.
Report and options
You get told what we found, where it is, why it likely failed, and what the realistic repair options are — a spot repair, a re-route, or replacing a run that is past saving. The price for the repair is quoted and agreed before it starts.
Why Leaks Hide So Well in Bay Area Homes
Two local conditions produce most of the hidden leaks we get called to. The first is soil. Much of the Bay Area sits on expansive clay that swells in winter rain and shrinks through the dry months. That constant movement works on buried pipe and on anything cast into or running beneath a slab, and joints that were fine for years eventually give up under it.
The second is the age of the pipework. Homes built before the 1960s were commonly plumbed in galvanised steel, which corrodes from the inside, narrows the bore and eventually perforates. Copper is not immune either — pinhole leaks happen, and hard water and high pressure do not help. In both cases the failure starts small and stays completely invisible until damage shows up somewhere else entirely.
That is why we detect before we dig. Water does not travel in straight lines: it follows the path of least resistance along pipe runs, joists, sub-base and soil, then surfaces wherever it can. Cutting where the damp shows is how people end up with three holes in a floor and a leak still running. Locating properly means one opening in the right place.
We use several methods together rather than relying on any one of them. A meter test proves there is a live loss rather than an old stain. Isolation and pressure testing narrow the search down to a single zone. Acoustic listening and thermal imaging pinpoint the spot itself. Camera inspection covers the drainage side, where listening equipment is of little use. Every method has blind spots, and cross-checking between them is what turns a probable location into one that is genuinely worth opening up.
What Affects the Price
We quote every job up front, so you approve the price before anything starts. These are the things that move it:
- Size of the property and how much pipework has to be isolated and tested
- Whether the leak is under a slab, buried outside, or hidden in a wall or ceiling
- Access — finished floors, tight crawl spaces and landscaping all slow the search
- Whether irrigation, a pool line or a second building has to be ruled out first
- Whether the drainage side needs a camera inspection as well as pressure testing
- How many methods are needed to confirm the location with confidence
- Distance, which can carry a fee on some on-site estimates
Most quotes are free and can be done from photos or video you send us. Some on-site estimates carry a fee based on distance, and we tell you that before we come out.
Leak Detection — Frequently Asked Questions
Straight answers, without the sales pitch.
Can you find a leak without breaking the floor?
Yes — that is the whole point of detection. Acoustic listening, thermal imaging and pressure testing all work through slab, soil and finishes. Opening up comes at the repair stage, and only at the spot we have marked. Detecting first is what keeps that opening to one place instead of several exploratory holes.
How can I tell if it is a slab leak?
Common signs are a warm patch on the floor, the sound of running water with everything shut off, unexplained damp at the base of a wall, and a meter that keeps ticking over overnight. None of them is proof on its own. A meter test plus isolating the under-slab pipework will confirm it quickly.
What is a meter test and can I do it myself?
You can. Turn off every tap, appliance and ice maker, then look at the small low-flow indicator on the water meter. If it moves at all over fifteen minutes with nothing running, you are losing water somewhere. Tell us what you saw when you call — it saves time at the property.
Do you find leaks in drains as well as supply pipes?
Yes, though with different tools. Drains are not pressurised so listening equipment is of limited use. We use camera inspection inside the line, plus dye and fill testing, to identify which section or fixture is losing water. That also shows up cracked joints and root intrusion at the same time.
What if the leak turns out to be on the irrigation?
It often is, and it is one of the first things we rule out. Irrigation runs on the same supply, is usually buried shallow, and leaks quietly into soil that is meant to be wet anyway. Isolating the irrigation valve and re-testing separates it from the house supply in minutes.
Do you repair the leak once you have found it?
Yes. Detection and repair are handled by the same crew, and we do not subcontract our service area. Once the leak is pinpointed we set out the repair options — spot repair, re-route or replacing a failing run — and quote it. You approve the price before any repair work begins.
Do you charge extra for nights, weekends or holidays?
No. We do not add overtime charges, ever. The rate you are quoted is the same whether we come out on a Tuesday morning or at 2am on a holiday weekend.
Are you licensed and insured?
Yes. Power Plumbing USA holds California contractor license #1082507 and carries full liability insurance. All work is performed to California Plumbing Code, and we pull permits where the job requires them.
Where We Provide This Service
We cover 15 Bay Area cities from our Union City base. See the full service area →