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Water main repair in Nassau and Suffolk County

Repair, replacement and new installation, residential and commercial

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SUFFOLK: 631-407-2873 NASSAU: 516-604-2651
Close-up of trenchless plumbing machinery and a plumber inspecting pipes for a Long Island, NY commercial repair project.
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Water main repair, replacement and installation

Most people who search for water main repair mean the line that runs from the street to their house, and that is the work we do most. We also repair and replace the larger mains themselves for commercial properties and site work.

Long Island Sewer and Water Main has worked Long Island water and sewer lines since 1983, family owned, out of Sayville, across Nassau County, Suffolk County and the five boroughs. On call 24 hours a day. Suffolk 631-407-2873, Nassau 516-604-2651.

Water main repair and leak repair

A water service line usually tells you it is failing before it bursts. The signs worth acting on:

Pressure that has dropped and stayed down, especially if it affects the whole house rather than one fixture. A water bill that climbed with no change in use. Wet ground, a soft patch or unusually green grass in a line between the street and the house, often showing up before anything appears indoors. Rusty or discoloured water on an older galvanized or iron line. The sound of running water with everything shut off.

A leak on the house side of the curb runs on your meter until it is fixed, which is why a service line leak is usually worth addressing quickly even when nothing has failed yet. If the leak turns out to be inside the house rather than in the buried line, that is leak detection and pipe repair instead.

Water main replacement and new installation

Some lines are worth repairing and some are worth replacing. A single clean break on a sound pipe is a repair. A line that has already leaked more than once, or an old galvanized or lead line, is usually a replacement, because repairing one section of a pipe that is failing along its length just moves the next leak down the run.

New installation is its own job: a new service to a building that never had one, a second service, an upsize for a property that has outgrown its line, or a water main extension on site work. Where the route allows it, these can often be run with directional drilling instead of an open trench.

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Water main contractors on Long Island

Water main work is not general plumbing. It is buried utility work, which means a permit from the authority that owns the main, a utility mark-out before anyone breaks ground, coordination with the water authority for the shut and the tie-in, and restoration of whatever the work crossed. A contractor who does this regularly handles that as part of the job rather than discovering it halfway through.

We work both sides of the property, water and sewer, which matters when a job turns out to involve both or when the two lines share a trench. If the problem is on the sewer side, that is sewer line repair.

Water main break and emergency repair

A water main break does not wait. If water is surfacing in the yard or the street, or pressure has dropped away suddenly, shut the water off at the main valve inside the building if you can reach it safely, and call. If the break is on the street side of the curb it belongs to the water authority, and we will tell you that rather than charging you to look at it.

Suffolk County 631-407-2873, Nassau County 516-604-2651, answered 24 hours a day, 7 days a week.

SUFFOLK: 631-407-2873 NASSAU: 516-604-2651

Water main services across Nassau and Suffolk

Repair, replacement, installation

Service line and main work, residential and commercial, including new services, upsizes and water main extensions.

Permits and mark-outs handled

Buried utility work needs a permit, a mark-out and coordination with the water authority. That is part of the job, not a surprise halfway through it.

Water and sewer, one crew

Both sides of the property, which matters when the two lines share a trench. On call 24 hours. Suffolk 631-407-2873, Nassau 516-604-2651.

Family owned since 1983

Forty years of Long Island water and sewer lines, worked out of Sayville, across Nassau County, Suffolk County and the five boroughs.

Water main repair near you on Long Island

Tell us what you are seeing and we will tell you whether it is a repair or a replacement. If the line can be replaced without opening the yard, that is trenchless water line replacement. If the leak is inside the building rather than in the buried line, that is leak detection and repair. For a new run on a fresh path, directional drilling.

Call 631-407-2873 in Suffolk or 516-604-2651 in Nassau.

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Blurry image of trenchless plumbing equipment used for sewer and water main services in Long Island, NY. The equipment is typically used for non-invasive pipe replacement and repair, ensuring minimal disruption to the property.

Water Main Repair FAQS

The water main is the distribution pipe running under the street, owned by the water authority. The service line runs from that main to your building, and from the curb in it is normally the property owner's.

In everyday use most people call the whole thing the water main, and that is fine. When someone asks us for water main repair they usually mean the service line to their house, which is the work we do most.

The split is normally at the curb stop or the property line: the authority owns the main and the connection in the street, the property owner owns the line from there to the building. Where exactly that line falls varies by municipality and by the age of the connection, so it is worth confirming with your own water authority.

Practically: if water is surfacing in the street, call the authority first. If pressure has dropped or the bill has jumped and the ground is wet between the curb and the house, that is usually yours and it is worth getting looked at.

The usual signs, roughly in the order people notice them:

  • A water bill that climbed with no change in use
  • Pressure that dropped across the whole building and stayed down
  • Wet ground, a soft patch or unusually green grass between the street and the house
  • Rusty or discoloured water on an older galvanized or iron line
  • The sound of running water with everything shut off

A buried leak often shows outside before anything shows indoors, which is why the bill and the wet patch usually arrive before the pressure drop.

Often, yes. Where the route and the pipe allow it, a service line can be replaced through small access pits rather than a trench the length of the run. That is trenchless water line replacement.

It is not always possible. Tight bends, some depths and some existing pipe conditions rule it out, and the only way to know is to look at the actual run rather than guess from the address.

Yes. Buried utility work needs a permit from the authority that owns the main, plus a utility mark-out before anyone breaks ground, and the shut and tie-in have to be coordinated with the water authority. Work in a road or sidewalk usually needs its own opening permit and restoration to the standard that authority sets.

Requirements differ by municipality. We handle the permitting as part of the job, and you should be wary of any quote that treats it as optional.

A typical residential service line replacement is a one to two day job on site once the permit is in hand. The permitting and the mark-out come first and are usually what sets the start date, not the digging.

Longer runs, road openings, commercial services and jobs needing a water authority shut take more. You will be told which yours is before the work is booked rather than on the day.