3

I'm helping a neighbor who is out of town. As luck would have it, the water main pipe they just had installed less than 4 days ago cracked and started leaking. When I checked it out I discovered that the line on the home side of the meter is some grade of gray schedule 80 PVC. It cracked a short nipple right where it entered into the coupling to the brass:

Point of failure

Meter box overview

So my first thought, is this really up to code / commonly used? There is going to be an awful lot of expansion / contraction of the exposed pipes here as the weather in this area (Santa Cruz California) ranges from lows in the high 20's to highs in the triple digits. In my mind, I would never think to use anything but a good grade of copper for this connection.

I want to make sure I'm not off base in my assumptions about the relative strength of copper vs PVC for a connection like this that sits above ground.

Note: There is an update shared in the accepted answer.

10
  • 7
    Don't know much else than you, but the first(top) picture the two pipes don't seem to be in straight line at the coupling . That will usually cause a leak at or near a joint, no matter what material is used.
    – crip659
    Commented Apr 30, 2022 at 19:06
  • 3
    That is right where the PVC should break; thread roots ( notches) next to much stronger, stiffer steel section. Any misalignment or soil movement cause high stress at that point. I have seen copper and steel used for main supply lines , not PVC but I seen only a few installations. The angular misalignment looks like the main problem. Unless thermal expansion/contraction could cause the angle mismatch , I doubt temperature was the cause. As you suggest , some thing with some flexibility would have been a help. Commented Apr 30, 2022 at 19:21
  • 2
    I don't have much to do with municipal supplies, but my default waterline "with some flex" is 160 or 200 PSI polyethylene (not pex) with insert barbed fittings and double stainless-steel worm-screw clamps.
    – Ecnerwal
    Commented Apr 30, 2022 at 19:38
  • 2
    Schedule 80 PVC is what we generally use for water meter to house underground- copper is a substantial upgrade and very desirable (until you see the cost). It looks to me that male adapter is cross threaded as well. Also the pipe may have been displaced/ dislodged by a careless back filling of the trench. One thing we do is sand both the inner fitting and the pipe ends and bevel the pipe end slightly (maybe 1/4") where glue will be applied to aid the glue's adhesion.
    – Kyle
    Commented Apr 30, 2022 at 20:11
  • 1
    I'm surprised it didn't leak from the beginning. It's crossthreaded, and the ptfe maybe helped stem the flow, but it's never right as is. Ground (earth) wiring is more often geen or green with yellow trace - that blue is there to help find the pipe years later when it's buried.
    – Tim
    Commented May 1, 2022 at 9:06

4 Answers 4

9

To answer your question about code yes schedule 80 is right.

With regard to expansion the earth temp doesn't vary enough to cause a problem in your area even though it’s probably only a foot below the surface.

as others point out that threaded connector looks to be cross threaded look at the narrow gap at the bottom of the pic compared to the much wider gap at the top.

I believe the easiest way to repair this would be to add a union and replace that bad connector If you cut close to the bad fitting a union should take up that space so that would be all you need to purchase worst case most big box stores do carry short sections of pipe if needed.

I am editing my answer and stating that it probably was not cross threaded but that when backfilled the pressure on the pipe broke at the weakest point , this is where conduit usually breaks also in rough environments.

As for copper in costal earth my comment below was meant to say corrosive soil conditions not crossover.

3
  • 1
    Thanks Ed. Appreciate the confirmation. I did some searching and it certainly seemed from the CA state codes I looked at that sch. 80 was not verboten. Unfortunately, in CA we also have to deal with movement caused by things other than temperature changes too. I'm still convinced that copper is a better option here. Commented May 1, 2022 at 5:11
  • Mark in many areas copper is better but close to the coast it is not the high salt content being a crossover is the issue, I started out north of San Francisco and earth movement is not an issue for the most part but tree roots are and in that case pvc actually bends fairly well. The problem wit copper is finding thick wall at a reasonable price get the thin stuff and you will have pinholes in some areas in less than 10 years.
    – Ed Beal
    Commented May 1, 2022 at 15:25
  • Gotcha Ed. Thanks. I actually have a short section of copper buried just a couple of inches below grade in my own yard for a sprinkler manifold. It's very sandy soil here, but I don't know if the PH is such that it would foster rapid corrosion. It's in a place where it is easy to check so I will be keeping an eye on it! Commented May 2, 2022 at 19:47
8

As for your other part of the question mentioned in your comment:

That blue wire is a tracer wire (also called locating wire or locator wire) and it is used to locate plastic pipes and other buried utility lines.

It is not a grounding wire.

The blue colour indicates a potable water line. Green is for sewer, and yellow for gas. It is a special wire with a polyethylene jacket rated for 30+ years under ground wet location.

When connected to a wire tracer transmitter it functions as an antenna and may transmit radio waves at a frequency between 500Hz and 200KHz.

The underground pipe can then be located by tracing the radio waves emanating from the wire antenna buried just on top of the plastic water pipe, with a device that looks a bit like a metal detector and is used in a similar swaying way while listening for an audible beep.

enter image description here

enter image description here

Image credits:

1
  • Wow. Super helpful info! I was also a bit concerned that a PVC pipe could be more easily damaged by digging than the galvanized it replaced. Nice to know there is a standard way to trace the pipe's location without having to dig. Commented May 1, 2022 at 14:45
4

Copper might be better, but in my opinion HDPE would be even better. (By the way, ground movement and flex are actually why lead used to be the standard for house-to-main pipe!)

Do not have that plumber back--anyone who can cross-thread a connection that blatantly and not notice, or worse just do it on purpose because the misalignment between the pipe angles was slightly hard to deal with properly, should be fired immediately. He's probably already been paid, but if not, don't pay him--if he takes you to small claims, just take your pictures with you. In fact, this sloppiness is so egregious that he should be reported to the state licensing commission. If he is in fact licensed--if he is not licensed and your neighbor hired some handyclown to work on his water line, well, lesson learned.

1
  • Thanks for the thoughts. It was a plumbing business that has multiple trucks and crews. I suggested that the neighbor request to see the actual license for the plumber who performed the initial connection that failed. I also suggest they self-request an inspection at the building department. I spoke to the plumber who showed up the next day. He seemed very experienced and made the repair with more room to handle flex. He spoke of the importance of looking at the code, not soliciting opinions. That was a good sign! Commented May 2, 2022 at 19:43
2

Answering my own question here about "suitability" of PVC Schedule 80:

This is spelled out in section 604.10 of the California Unified Plumbing code:

enter image description here

This table lists the ATSM standards which are required:

enter image description here

It's unlikely anyone can provide an estimate of how frequently each of those materials is actually selected. I would venture to guess that Sch. 80 is fairly common as it is suitable and significantly cheaper than copper.

Update on the issue

Thanks to all who commented on my question. I apologize for soliciting opinions initially. Stack Exchange is a Q&A site and specifically prohibits this. I should have known better. I've been answering questions for years on stackoverflow.com. 😞

The company who did the initial work finally sent someone (a different plumber) out the next day to fix it. The connection was re-done with a much longer section of pipe feeding directly into the meter and several angles inserted to allow the pipe room to flex without snapping. The work seems like it should hold up better now. Here is a photo:

enter image description here

The initial work was not cross threaded as was suggested in the comments. It looked like that was the case because it was cracked and at an angle.

I encouraged the neighbor to seek an inspection from the local building department. It's technically required and was never done by the plumber initially. I will post any follow-up on that.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.