First steps: shut off the water and stay safe
If you think the main line to your house is leaking, act quickly to limit damage and water loss.
- Shut off the main valve where the line enters the house. If it will not turn or does not stop the flow, close the utility’s shutoff at the meter if you are allowed to operate it. In many places that valve is for utility use only, so check with your water provider first. They can often shut it off for you.
- Keep people and pets away from flooded areas, especially a basement or crawlspace where water could be near electrical panels, outlets or appliances. Do not stand in water to touch electrical equipment. If water is reaching your electrical panel or outlets, call your utility or an electrician.
- Watch for sinkholes or soft ground. Water from a buried line can undermine soil. Keep clear of any ground that looks sunken or soft.
- Call a plumber or your water utility, depending on where you think the leak is (see below).
Signs of a leaking water main
- Soggy patches, pooling water or unusually green, fast-growing grass in the yard when it has not rained
- A higher water bill with no change in how you use water
- Lower water pressure throughout the house (see how to fix low water pressure for other causes)
- A hissing or running water sound near where the supply enters the house
- A water meter that moves when all fixtures are off
- Wet or damp spots in a basement or slab floor near the entry point of the line
Many of these overlap with other problems, so confirm with a meter test. See the broader list in signs of a leaking pipe.
Confirm it with the meter test
- Turn off every tap and appliance that uses water, inside and out, including irrigation.
- Look at the meter’s low-flow indicator, or note the reading.
- If it is moving, water is going somewhere. Close the main shutoff valve at the house.
- Check the meter again. If the indicator stops, the leak is on the house side of the valve (inside plumbing). If it keeps moving, the leak is likely in the buried line between the meter and the house, or the shutoff valve itself may not be sealing fully.
If the shutoff valve is old or stiff, forcing it can break it. Be gentle, and if it is stuck, ask a plumber to replace it.
Who is responsible for the line?
Responsibility varies by location, so check rather than assume. In many areas:
- The utility owns and maintains the main in the street and often the line up to the meter.
- The homeowner owns the service line from the meter, or from the property line, to the house.
But some utilities, cities and counties set the boundary differently, and some offer optional service line protection programs. Call your water provider and ask where their responsibility ends. Your property records, utility website or plumber may also help. It is also worth reading your homeowners policy, since coverage for buried line leaks varies and may require an endorsement.
Can you fix it yourself?
For a buried main, usually a professional should handle the repair. Reasons include digging near other buried utilities, working in a trench safely, meeting local code, and pressure-testing the line afterward. Permits or inspections may be required.
Things a homeowner can reasonably do:
- Shut off the water and document the problem with photos and meter readings.
- Contact the utility and get quotes from licensed plumbers or contractors.
- Make the area safe, for instance by marking or fencing off a soft or sunken spot.
On exposed, accessible pipe, a temporary clamp or repair coupling can sometimes hold until a plumber arrives. Sealing compounds and tapes on a leaking PVC pipe are generally short-term measures, and they are not a reliable permanent fix on a pressurized main. A proper repair usually involves cutting out the damaged section and installing a coupling or new pipe.
Repair options
- Spot repair. If the damage is limited, a crew digs down, cuts out the damaged section and splices in new pipe with a coupling.
- Replacement. If the pipe is old, corroded or leaking in several places, replacing the whole run may be more sensible than repeated spot repairs. Material choices, such as copper or plastic, are discussed in copper vs plastic water pipe.
- Trenchless methods. Some contractors can pull or burst a new line through the old route with less digging. Suitability depends on soil, depth and the existing pipe, so ask whether it is an option for your property.
Before anyone digs
In many countries, you or your contractor must request a utility locate before excavating, which marks buried gas, electric, telecom and water lines. In the United States, this is generally done through 811. Hitting a gas or electric line is dangerous. Do not dig near suspected buried lines yourself without a locate, and if you smell gas or see damage to a gas line, leave the area and call the gas utility or emergency services.
What to ask a plumber or contractor
- Are you licensed and insured, and will you pull the required permits?
- What is the cause, and is it a spot repair or a full replacement?
- What material will you use, and what warranty comes with the work?
- How will the yard, driveway or landscaping be restored, and is that included in the quote?
- How long will the water be off?
Get more than one written quote when time allows. If the leak is part of wider pipe aging inside the house, see replumbing a house for the larger picture.