Pipeline Pressure Testing
Isolating a line and monitoring its pressure confirms whether it leaks, and which section — hot or cold, inside or outside — is responsible.
Leak Location Services · Alhambra, CA
Underground Main Line Leak Detection in Alhambra, CA
The main service line runs underground from the meter to your home, and when it leaks the signs are easy to miss or misread: a soft patch of lawn, a bill creeping up, pressure dropping. Underground main line leak detection first separates the service line from in-home plumbing and from irrigation, then pinpoints the leak along its buried route.
Open 24 hours, 7 days a week · Serving Alhambra & the San Gabriel Valley
Signs you may need this service
- A persistently wet or unusually green patch of yard
- Water bill increases with no in-home explanation
- Reduced water pressure throughout the house
- Meter movement that stops when the house shut-off is closed
- Sound of water near the meter or along the line's route
Individual symptoms do not always prove a leak — they justify a proper investigation, which is what this service provides.
What this service investigates
The buried supply line from the meter to the building entry point, its shut-off valves and connections, and the separation between house plumbing and irrigation feeds.
Who it is for
- Homes with wet yards or unexplained outdoor water use
- Properties with low pressure and rising bills together
- Anyone facing a service-line repair quote who wants the location verified first
How the process works
1
Meter test with the house isolated, to prove whether the loss is in the service line, the house, or irrigation.
2
Trace the buried line's route across the property.
3
Pinpoint along the route with acoustic listening or tracer gas, depending on depth, material and noise.
4
Mark the leak point and depth estimate, and explain repair options for that section.
Equipment & methods
Meter and isolation testing, line tracing, acoustic correlation/listening, and tracer gas for deep or quiet leaks.
What affects the diagnosis
Irrigation leaks can mimic a main-line leak, which is why isolation comes first. Depth, soil type, paving and plastic pipe can affect precision. A marked location is an evidence-based pinpoint, not an X-ray — the repair opening verifies it.
What you receive
Confirmation of which system is leaking, the marked leak location along the route, and the reasoning, so a repair crew digs once, in the right place.
Read more: our guide related to underground main line leak detection · All services · Service areas
Underground Main Line Leak Detection FAQs
How do I know it is not my sprinklers?
By isolation. With irrigation shut off at its own valve and the house isolated, the meter test shows which system is still losing water. That check is built into the visit.
Will my yard need to be dug up to find the leak?
No. Detection is done from the surface. Digging is only for the repair, and only at the marked point.
Can a main-line leak affect water pressure?
Yes — a significant leak diverts water before it reaches the house, and pressure and flow can both drop. Low pressure alone does not prove a leak, which is why the meter test comes first.
What if the leak is under the driveway?
It can still usually be pinpointed from the surface with acoustic or tracer-gas methods. The repair under paving is a separate scope and is explained as such.
Related services
Tracer Gas Leak Detection
A safe tracer gas introduced into a drained line escapes at the leak point and is detected at the surface — ideal for tiny or silent leaks.
Acoustic Leak Detection
Electronic listening equipment picks up the sound of pressurised water escaping a pipe, so the leak can be pinpointed through floors and walls.
Think you have a hidden leak?
The sooner a leak is confirmed and located, the less water is wasted and the less damage spreads. Call now, or send a short request and describe what you are seeing.
Open 24 hours, 7 days a week · 1065 Westminster Ave, Alhambra, CA 91803