How Do You Fix an Underground Water Pipe Leak?

Who owns the underground pipe, you or the utility?

Ownership depends on your utility, not on one national rule. In every utility we checked, the homeowner owns or maintains part of the buried line, but the exact split changes by city.

Check your utility's ownership page first

Search your own water utility's name plus "service line ownership" or "what's yours, what's ours" before you call anyone. The table above shows four real examples, not a universal rule.

A leak between the street main and the meter

In the Nashville, North Carolina example, a leak in the main under the street, or in the line between the main and the meter, goes to the town. For the water main itself, see whether the city or the homeowner is responsible for a leaking water main.

A leak on your side of the meter

Past the meter, the line is usually yours. Denver Water says property owners are responsible for service lines that run all the way into the home, and in Fremont, Nebraska, the customer owns the corporation valve and the service line.

Calgary's bylaw puts a similar duty on the owner: keep the water service connection in good repair and pay for the repair. Calgary is a Canadian city, so treat this as one model of how a utility can assign the duty, not as a US rule.

How do you confirm the leak is underground?

Denver Water's meter test separates an underground leak from one inside the house. Read the meter with no water running, wait 30 minutes or more, then read it again.

The meter test with the house shut-off valve closed

1. Make sure no water is running anywhere in the house.
2. Note the gallon calculating sweep hand or the number wheels on the meter.
3. Wait 30 minutes or more, then look at the meter again.
4. If the reading moved, close your house shut-off valve and read the meter once more. If it still moves, Denver Water says the leak is underground.

This differs from the EPA's WaterSense meter check, which asks you to recheck after two hours and points toward a leaky fixture or hose, not a buried line. Use the shut-off-valve step above to confirm an underground leak specifically.

Warning signs: a jump in your bill, soggy ground or standing water

The Town of Nashville, North Carolina lists two signs worth checking: a sudden jump in your water bill, and soggy ground or standing water in the yard with no obvious cause.

See how to tell whether a leak sits before or after the meter if your test points to the meter area itself rather than the yard beyond it.

Where do you shut off the water, and should you touch the street valve?

Shut off the water at your property's own shut-off valve, the stop tap. Leave any valve at the street alone unless your utility tells you to operate it.

Shut off the house valve first

The Town of Nashville, North Carolina says the property's shut-off valve, or stop tap, must be maintained by the homeowner. See how to find and turn off your main water shutoff valve if you are not sure where yours is.

Do not operate the street valve unless the utility says so

Access to the meter or the main shut-off valve can be the utility's job, not yours. In Calgary, the city's locator contacts the homeowner to get access to the meter or main shut-off valve to test a suspected private-side leak, rather than asking the homeowner to operate it alone.

• Do not dig before you call 811.
• Do not operate a street or city-owned valve unless your utility tells you to.

If you are on a private well

One older how-to guide suggests turning off or unplugging the well pump once you find the leak. Treat this as general advice rather than a verified rule, and check with a well or pump professional for your own setup.

Do you need to call 811 before you dig?

Yes. Anyone planning to dig should contact 811, or their state's 811 center, before digging, and the call is free.

Why you call before any digging

811, the free national before-you-dig service, advises calling a few business days before you begin. Crews mark the approximate location of buried utility lines with paint or flags.

The Nevada Public Utilities Commission says a homeowner digging with mechanical equipment must also call 811, and hitting an unmarked line without calling first can bring fines and repair costs.

Will your private line be marked?

The 811 page does not address water lines or private-side marking directly, so ask 811 or your locator whether your own service line will be marked. Nevada's utility locator marks water lines in blue where the line runs from the main in the street.

How do you find the exact leak without digging up the yard?

Utilities usually pinpoint a buried leak by listening, not by digging randomly. Crews use listening rods and electronic instruments to find the spot, then expose only that point.

Listening and locating: utility tools

The Portland Water Bureau says crews listen at a hydrant, a service line, or elsewhere on the pipe's path, using listening rods to hear leaks on pipe that is not visible above ground.

An electronic instrument can convert the vibration of escaping water into sound, and a correlator calculates the leak's position, according to the Southwest Florida Water Management District. These are utility tools, not typical homeowner equipment.

Ask the utility to locate the leak

Before you hire anyone to dig, ask your utility whether it offers leak locating on the private side. This can save you from opening ground in the wrong spot. For the steps that come before that call, read the full walkthrough for finding an underground water leak.

Exposing only the repair point

Once a leak is located, a hydrovac procedure, using pressurized water and a vacuum system, can expose the pipe at just that spot instead of trenching the whole yard, according to the City of Calgary. The next section covers this and other repair methods.

Can you fix an underground water pipe yourself, or do you need a licensed plumber?

Check your utility's rule first. Denver Water says most leaks are easy to fix while others may need a plumber, Nashville, North Carolina says work beyond basic upkeep needs a licensed, insured plumber, and Fremont, Nebraska requires a city-licensed master plumber.

Check the rule for your utility first

None of the sources we checked give a skill test or a DIY threshold for an underground repair, so do not assume one. Digging into, cutting, or joining a line the utility owns should wait until the utility or a licensed plumber confirms who does the work.

When the work is beyond basic upkeep

Once the job goes past basic upkeep, such as cutting out a section of pipe or joining a new one, Nashville's rule is to hire a licensed, insured plumber. See what a permanent pipe repair involves and when a patch is not enough for the indoor side of that same decision.

Which repair method fits: spot repair, trench, or trenchless?

Calgary's city guidance lists three repair methods for a service line: a hydrovac spot repair at the leak point, a trench from the city's service valve to the house, and a trenchless service pull that installs a new line with minimal digging. A plumber or your utility can tell you which one fits your leak.

Spot repair with hydrovac

A hydrovac crew exposes only the leak point with pressurized water and a vacuum system, Calgary says, avoiding a full trench for one isolated spot.

Trench excavation

A trench excavation opens the ground from the utility's service valve to the house, the more traditional option for a longer section of bad pipe.

Trenchless service pull

A trenchless service pull installs a new line from the house to the service valve with minimal digging. Ask your plumber or utility whether your soil and layout fit this option.

Cut out and replace a section (one how-to guide)

A 2008 how-to guide describes cutting out the damaged spot, leaving extra sound pipe on each side, and replacing the whole line if it looks worn throughout. Treat the exact cut length and pipe material in that guide as general, dated advice, not a verified code or standard.

Do not rely on a clamp or patch as a permanent fix for a buried line; no source in our research confirms one as permanent underground. For a temporary clamp on an outdoor line while you wait for help, see temporary emergency repair methods for an outdoor water line.

Do you need a permit before the repair?

Sometimes. In Fremont, Nebraska, you must get a permit from the Department of Utilities before any repair work begins.

The sources we checked do not set one national permit rule, so ask your own utility or local building department before you start, and ask whether an inspection is needed before the trench is closed.

How much does it cost to fix an underground water pipe?

No verified dollar range is available for this repair. The City of Calgary says the cost of a repair can be highly variable, depending on the contractor and the type of water service repair, so ask any contractor for an itemized estimate that names the repair method.

Three things tend to drive the price: the repair method (spot repair, trench, or trenchless), how much ground has to be opened, and the contractor you hire. Underground repair tends to cost more than an indoor fix simply because of the digging involved. For a broader breakdown, read the full cost guide for underground water pipe repair.

Will insurance pay for the repair?

A basic homeowners policy typically does not cover these repairs, according to Calgary's city guidance, but Nashville, North Carolina says some line repairs may be covered. Check your own policy and ask your insurer about coverage for the service line.

This is general information, not insurance advice, so confirm the details with your own insurer. See how insurance treats burst pipe claims for the broader coverage picture beyond underground lines.