It had been leaking for five months. What finally settled it was a drought: the ground stayed wet when nothing else in the county was. We dug down four feet and found a one inch poly line, which was strange, because the pipe entering the house is copper.
This is a real job in Andover Township, with the real numbers on it, because a case study without figures is just a story.
Five months, and a drought that gave it away
The homeowner had known something was wrong for a while and had not landed on a water line. That is normal. A service line leak underground does not announce itself the way a burst pipe in a wall does. There is no sound, often no pressure complaint worth calling about, just an area of ground that is wetter than it should be, which for most of the year looks like ordinary New Jersey.
Then it stopped raining, and the wet patch stayed. That is the tell. If one area of your yard stays soft through a dry spell while everything around it goes hard, that water is coming from somewhere other than the sky.
We went out with M. Miller Plumbing, who we bring in for the plumbing side of this work, and started digging.
A poly line where a copper line should be
About four feet down we found a one inch polyethylene line.
That did not add up, because the service entering the house is one inch copper. A run does not change material on its own. What it means is that somewhere in the fifty or so years this line has been in the ground, somebody made a spot repair or replaced a section, and did it in poly.
So the homeowner had a copper service with a poly section spliced into it, and had no idea, because nothing on the surface tells you that. Whoever did the work is long gone and there is no record of it. That is extremely common on older services and it is worth knowing about your own: the material at the house does not prove the material in the yard.
Why it failed, and why it will fail again
The crack was small, on the bottom of the pipe, on the inside.
There was no dramatic reason for it. No rock sitting on it, no dig damage, nothing anybody did. Just an old pipe that had not been bedded in sand, sitting in ground full of sharp stone. Over years of freeze and thaw the ground moves, and a pipe with no cushion under it moves with it, working against whatever is next to it until something gives.
That is the whole argument for sand bedding in one sentence. We dig a water line trench to about forty six inches so the pipe can sit at forty two on four inches of sand. It is not detail work and it is not padding an invoice. It is the difference between a line that fails in fifty years and one that fails in fifteen.
What we did, and what we told him
The spot repair: $4,750. The homeowner asked for the repair, and the repair is what we did. Cut out the failure, make the connection, backfill, compact and regrade the area.
Then we gave him the honest version, which is that this will happen again. A fifty year old line with an unrecorded splice and no sand under it has told us what it is going to do. The next crack is not a question of whether.
Full replacement of the 500 foot service: $17,400. And our recommendation was to do it now rather than in January, because a water line that fails in a deep frost is a different and much worse job, for us and for him.
We did not refuse the repair to force the replacement. He asked for the repair, he got the repair, and he got the real number for the permanent fix alongside it so the decision was his to make with everything on the table.
Why we specified poly on a job where we usually argue for copper
We have written elsewhere that copper outlasts poly, and we stand by it. On this job we specified poly anyway, for three reasons that all had to be true:
- It is a 500 foot run. Copper material typically costs ten to twelve times what poly costs, and over 500 feet that is not a rounding difference, it is most of the project.
- It fits the customer's budget. A recommendation the homeowner cannot afford is not a recommendation, it is a way of doing nothing for another year.
- Poly is an approved material in his town. That is not universal. A number of New Jersey municipalities have restricted or prohibited poly for water services, and the permitted materials are set by your town or utility rather than by any statewide rule. We checked. If it had not been approved there, this would have been a copper job regardless of the run length.
The one thing that would have overridden all three is contaminated ground, because petroleum can permeate plastic pipe and cannot permeate metal. No reason to suspect it here.
Being right about materials in general and being right about this property are two different jobs.
What is actually on site for a job like this
People ask what a water line replacement involves, and the honest answer is more equipment than most expect, because each machine is solving a different problem:
- Kubota KX040 excavator. Opens the trench. Small enough to work a residential property without destroying what is around it.
- Five ton compaction roller. The driveway here is stone, and stone needs to be rolled back to a surface somebody can drive on rather than raked flat and left to rut.
- Wacker Neuson jumping jack. Compacts the trench itself in lifts. This is the machine that decides whether you get a settled line across the lawn next spring.
- Dump truck. Hauls in the sand for the bedding, which is the material the failed pipe never had.
- Mini skid steer. Moves the sand around the site. Five hundred feet of trench is a lot of sand, and the alternative is a crew wheelbarrowing it all day, which is slower and wrecks people.
That last one is worth saying plainly. Keeping the crew from being worn out by lunchtime is not a comfort item, it is why the compaction at foot 480 is as good as the compaction at foot 20.
Common questions
How do I know if my underground water line is leaking? The most reliable sign is ground that stays wet when it has no reason to be. If one area of the yard stays soft through a dry spell while everything around it dries out, suspect the service line. On this job the homeowner had been living with it for five months and only became sure during a drought. Other signs are a jump in the water bill, a drop in pressure, and in winter an area of ground that stays unfrozen or clear of snow.
How much does it cost to repair a leaking water line versus replacing it? On this job the spot repair was $4,750 and replacing the full 500 foot service was $17,400. That is roughly $35 a foot for the replacement, which is what a long run does to the per-foot price, since mobilization is spread over more distance. A short service costs more per foot than a long one.
Should I repair a leaking water line or replace it? Repair a line that failed for a reason, such as dig damage or a single bad section. Replace one that failed because of what it is: an old line, a wrong or unrecorded material, or a pipe that was never bedded properly, because those conditions have not gone anywhere and the next failure is a matter of when. If a replacement is coming, doing it outside a deep frost is materially better than doing it during one.
Why would my water line be a different material than the pipe at my house? Because somebody repaired or replaced a section at some point and used what they had. A copper service with poly spliced into it is common on older properties, and there is usually no record of it. The material at the house does not tell you the material in the yard.
Why does a water line need to be bedded in sand? To keep it off anything sharp. Ground moves through freeze and thaw, and a pipe with no cushion under it moves against whatever is around it. On this job the failure was a small crack on the underside of a line sitting in sharp stone with no sand under it, with no other cause. We dig to about forty six inches so the pipe sits at forty two on four inches of sand.
Costs for this work across the board are on what this work costs, and the wider service is on our sewer and water line page.
Still not sure how this applies to your property? That is what a free on-site estimate is for. Call 862-268-2510 or tell us what is going on, and we will give you a straight answer, including when the answer is that you do not need us.