Main Water Line Replacement in Southern California
What Is the Main Water Line?
The main water line, also called the water service line, runs underground from your water meter, usually near the street or sidewalk, to the point where it enters your house. Every fixture and appliance in the home depends on it. In most Southern California water districts, the utility owns the meter and the pipe on the street side of it, and the property owner owns the line from the meter to the house. If a leak turns out to be on the street side of the meter, it is the utility’s repair, and we will tell you so.
Many older homes across Los Angeles County still have their original galvanized steel service line, which corrodes from the inside out the same way galvanized house piping does. Homes plumbed between 1978 and 1995 may have polybutylene, a plastic pipe with a long record of failures. Either material is a reason to plan the replacement rather than wait for the leak.
Signs Your Main Water Line Is Failing
A failing service line is buried, so the evidence usually shows up somewhere else first. Watch for these signs:
- Low Pressure Throughout the House – When every faucet is weak at once, the problem is upstream of all of them, often in a corroded or leaking main line.
- A Water Bill That Keeps Climbing – An underground leak runs around the clock, and the bill is often the first place it shows.
- A Meter That Moves With Everything Off – If the meter’s leak indicator turns while no water is in use, water is going somewhere.
- Wet Ground Between the Meter and the House – Soggy soil, a soft spot, or a strip of grass that stays greener than the rest of the yard can mark a leak below.
- Water Surfacing at the Sidewalk or Driveway – Water seeping up through cracks in concrete near the meter is a classic service line leak.
- Rusty or Discolored Water at Every Tap – Common when the service line is galvanized and corroding from the inside.
A leak inside the house can produce some of the same signs. When the cause is not obvious, our exploratory leak search finds it before anyone digs.
Repair the Line, or Replace the Whole Run?
Not every leak means a new line. A single failure in a copper service line that is otherwise sound can be repaired: we expose the failed section, replace it, and test the line. Galvanized and polybutylene lines are a different story. Galvanized pipe is corroding along its whole length, so a repair on it is usually followed by another leak somewhere else on the run, and polybutylene that has started to fail rarely stops at one spot. On either material, replacing the line from the meter to the house is the fix that lasts, rather than paying to dig up the same yard again next year.
Because Repipe Once does both the detection and the replacement, our recommendation follows what we actually find, not the bigger invoice. If a repair is the right job, we will say so.
Our Main Water Line Replacement Process
A main line replacement is mostly planning: knowing exactly where the line runs and where it failed means a smaller trench and a shorter shutoff.
- Confirm and Locate – We confirm the leak at the meter, then trace the path and depth of the line so we are not digging blind.
- Plan and Estimate – You get a clear explanation of what we found, the route for the new line, and an upfront, transparent estimate.
- Permit – We can pull the plumbing permit for you before work begins, or you can pull it yourself if you prefer.
- Trench Only Where Needed – We open the ground only where the run requires it. Where a driveway or walkway sits over the old line, the new one does not always have to follow the same path, and we will show you the options.
- Install and Pressure-Test – The new line is connected from the meter side to the house and pressure-tested before anything is backfilled.
- Inspect and Restore – The work is inspected, the trench is backfilled, and we restore the work area before we leave.
We replace main water lines throughout Los Angeles, the San Gabriel Valley, the Inland Empire, and Orange County. See all the locations we serve.
Main Line Replacement With a Whole-House Repipe
If the service line is galvanized, the pipes inside the house are often the same age and the same material. A whole-house repipe covers the supply lines from the meter through every fixture, and when the underground line has corroded, leaks, or is dropping your pressure, we replace that run as part of the same job. The result is new pipe from the meter to every faucet, planned as one project.
We repipe in both copper and PEX, and our guide to copper vs PEX repiping covers how to choose. If the leak turns out to be under the house rather than in the yard, slab leak detection pinpoints it without breaking concrete to search.
Testimonials
Why Choose Repipe Once for Main Water Line Replacement?
A main line replacement means opening the ground on your property, so the job should be planned before the first shovel goes in.
- Detection Before Digging – We locate the line and the leak first, so the trench is small and in the right place.
- Licensed Plumbing Contractor – Repipe Once is a licensed California contractor, CSLB #1004038.
- Permitted, Tested, and Inspected – Every new line is pressure-tested before backfill and inspected before we close out the job.
- Transparent Pricing – Free estimates, and the price we quote is the price you pay. Financing is available through our Hearth partner program.
- Done Once, Done Right – Workmanship on every Repipe Once installation is warranted for 15 years. Full terms are on our limited warranty page.
With Repipe Once, you get a new main line from the meter to the house that you will not have to think about again.
Frequently Asked Questions
Who is responsible for the main water line, me or the water company?
In most Southern California water districts, the utility owns the meter and the pipe on the street side of it, and the property owner owns the line from the meter to the house. If you are not sure which side a leak is on, we can find out before anyone digs. If it is on the utility’s side, we will tell you to call them.
How can I tell if my main water line is leaking?
Turn off every faucet, appliance, and irrigation system that uses water, then look at your water meter. Most meters have a small leak indicator, a triangle or dial, that turns whenever water is flowing. If it moves while nothing is on, water is leaking somewhere. Check that no toilet is running first. If the meter still moves, call us and we will locate the leak.
Will you have to dig up my whole yard or driveway?
No. We locate the line before we dig and trench only where the run requires it. Where a driveway or walkway sits on top of the old line, the new line does not always have to follow the same route, and we will walk you through the options when we quote.
Does main water line replacement need a permit?
Yes. We can pull the permit for you, or you can pull it yourself if you prefer. When we pull the permit, we also schedule the inspection and meet the inspector on site. Every new line is pressure-tested before backfilling.
Will a new main line fix my low water pressure?
When the cause is a corroded service line, yes. Galvanized pipe corrodes from the inside out until the opening closes up, and a new line restores full flow. If the pressure problem is somewhere else, such as a failing pressure regulator or corroded piping inside the house, our inspection will show it before you commit to a replacement. We test pressure regulators and replace them when they have failed, so a regulator problem gets fixed as a regulator problem.
Is low water pressure my pipes or the pressure regulator?
Either, and a test tells them apart. The pressure regulator sits where the service line enters the house and steps street pressure down; when it fails, pressure drops or swings at every fixture. Corroded galvanized pipe narrows from the inside and produces the same symptom. We gauge the pressure at a hose bib, test the regulator, and check the line before recommending anything. We test and replace pressure regulators, and if the regulator is the whole problem, that is the whole job.
Does insurance cover main water line replacement?
Policies vary. Many homeowners policies cover damage a leak causes but not the cost of replacing a worn-out line, and some owners carry separate service line coverage. Some water utilities will also consider a bill adjustment once a leak is repaired, so keep your invoice. We provide the documentation your insurer or utility asks for.
Does a whole-house repipe include the main water line?
A whole-house repipe covers the supply lines from the meter through every fixture. When the underground line between the meter and the house has corroded, leaks, or is dropping your pressure, we replace that run as part of the same job.
Request a Free Main Water Line Estimate
If your pressure has dropped, your water bill keeps climbing, or the ground between the meter and the house will not dry out, your main water line may be failing. Repipe Once locates the problem, replaces the line, and tests it before backfilling, across Los Angeles, the San Gabriel Valley, the Inland Empire, and Orange County.
Get a new line from the meter to the house that is done once, done right.