Plumbing Question on 1/4 mile 2" buried PVC water line with Compression Connectors

[MountainBuck]

I live in a remote area and have a quarter mile buried water line that is my responsibility to the metro water line at the main road.

My neighbor had a leak he noticed in his water bill and had a plumber dig up our dirt road to temporarily install a boiler valve for the purpose of a leak detection company to pump in nitrogen and listen for the escaping gas hiss to locate the leak. However, in doing this the plumber nicked my line which is very close to my neighbors line.

At no cost to me, the plumber cut out the nick he made in my line and installed two of these compression fittings and a small section of 2 inch PVC.

The boiler valve was installed and the leak detection company came out and laughed at the work because it was worthless. Right past this area the pipe goes downhill. They knew the leak was in the downhill area and the leak detector guy said "gas doesn't go downhill." So he never did anything, drove away and billed for the visit.

Eventually, after long painful discussions about what to do next, I reminded my neighbor that this same plumber installed a compression union down hill a few years ago when he had a previous leak. The plumbers and my neighbor finally agreed to act on my hunch and dug up this existing compression fitting and found that it was leaking.

The reason why this compression fitting had failed was that at this point, the 2" water line starts a large bend where the pipe must turn 180 degrees down the driveway. We call this area of driveway "the switchback." If you zoom in on the picture you should be able to see that the pipes don't exactly line up in the compression fitting. There is great pressure of the pipe and the water in this fitting.

This got me to wondering if there was a better solution to this issue.

What I found was confusing and contradictory. The first solution would be to use a the PVC cement bond, but this plumber said that would be weak and didn't want to do it. I found references to a "stiffener" that could be added into the ends of the pipe when using a compression fitting but when I looked online, all I could find were the stainless steel stiffeners for other types of plastic pipe and none said specifically PVC. The last solution I found was the larger PVC threaded unions but those would still have to be cemented into place.

Has anyone seen or used a "stiffener" inside a PVC pipe in conjunction with a PVC compression fitting? Should I be looking at something else?

By the way, the plumbers charge $500 for each time they dig up and install one of these ball valves, so my neighbor had to install about 3 or 4 of them and that cost builds quickly. The ball valves were installed to narrow down the location of the leak the last time it happened.

 

[mrmikey]

What's the reason you can't use a conventional stainless steel barb fitting and s/s hose clamps? Underground is one place I wouldn't trust a push on.

 

[pmsmechanic]

You can also fuse the plastic together. It's a tool that squares off the ends of the pipe and the end result is a fused joint done with heat. I have no idea what pressure ratings on it are but it's common pipe repair in the natural gas industry.

 

[MapleLeafFarmer]

What's the reason you can't use a conventional stainless steel barb fitting and s/s hose clamps? Underground is one place I wouldn't trust a push on.
View attachment 3084003 View attachment 3084004

we use barbs/clamps for poly water pipe but rigid pvc pipe like we use for pools we simply glue fittings / couplers /etc... unless in a tight or wet area where glue can be problematic. I see compression stuff used on pvc when guys are too lazy to make things dry and clean. For swimming pools especially as getting pipes dry and clean can be difficult due to all the wetness.

 

[dicktill]

I live in a remote area and have a quarter mile buried water line that is my responsibility to the metro water line at the main road.

My neighbor had a leak he noticed in his water bill and had a plumber dig up our dirt road to temporarily install a boiler valve for the purpose of a leak detection company to pump in nitrogen and listen for the escaping gas hiss to locate the leak. However, in doing this the plumber nicked my line which is very close to my neighbors line.

At no cost to me, the plumber cut out the nick he made in my line and installed two of these compression fittings and a small section of 2 inch PVC.

The boiler valve was installed and the leak detection company came out and laughed at the work because it was worthless. Right past this area the pipe goes downhill. They knew the leak was in the downhill area and the leak detector guy said "gas doesn't go downhill." So he never did anything, drove away and billed for the visit.

Eventually, after long painful discussions about what to do next, I reminded my neighbor that this same plumber installed a compression union down hill a few years ago when he had a previous leak. The plumbers and my neighbor finally agreed to act on my hunch and dug up this existing compression fitting and found that it was leaking.

The reason why this compression fitting had failed was that at this point, the 2" water line starts a large bend where the pipe must turn 180 degrees down the driveway. We call this area of driveway "the switchback." If you zoom in on the picture you should be able to see that the pipes don't exactly line up in the compression fitting. There is great pressure of the pipe and the water in this fitting.

This got me to wondering if there was a better solution to this issue.

What I found was confusing and contradictory. The first solution would be to use a the PVC cement bond, but this plumber said that would be weak and didn't want to do it. I found references to a "stiffener" that could be added into the ends of the pipe when using a compression fitting but when I looked online, all I could find were the stainless steel stiffeners for other types of plastic pipe and none said specifically PVC. The last solution I found was the larger PVC threaded unions but those would still have to be cemented into place.

Has anyone seen or used a "stiffener" inside a PVC pipe in conjunction with a PVC compression fitting? Should I be looking at something else?

By the way, the plumbers charge $500 for each time they dig up and install one of these ball valves, so my neighbor had to install about 3 or 4 of them and that cost builds quickly. The ball valves were installed to narrow down the location of the leak the last time it happened.

I feel your pain ...

Good luck, Dick

 

[4570Man]

What's the reason you can't use a conventional stainless steel barb fitting and s/s hose clamps? Underground is one place I wouldn't trust a push on.
View attachment 3084003 View attachment 3084004

Those only work for poly not pvc.

 

[4570Man]

I don’t like to keep fixing water line. After the first repair is made the trend seems to keep on as your neighbor is experiencing. I’d about start up the ditchwitch and replace all of it. If that’s absolutely not an option I’d replace the bent section so you can at least couple it back on straight and correctly instead of fighting with misaligned pipe. My solution seems kinda excessive which it is but he’s already at $2000 in plumber visits plus the lost water which is frequently beyond $1000 per leak and it’s not even fixed yet.

 

[Fishin-4-a-Livin]

These are the couplings that I use for my buried water lines. Very heavy duty compression fitting.

This particular one is 1 1/4”

 

[ponytug]

I live in a remote area and have a quarter mile buried water line that is my responsibility to the metro water line at the main road.

My neighbor had a leak he noticed in his water bill and had a plumber dig up our dirt road to temporarily install a boiler valve for the purpose of a leak detection company to pump in nitrogen and listen for the escaping gas hiss to locate the leak. However, in doing this the plumber nicked my line which is very close to my neighbors line.

At no cost to me, the plumber cut out the nick he made in my line and installed two of these compression fittings and a small section of 2 inch PVC.

The boiler valve was installed and the leak detection company came out and laughed at the work because it was worthless. Right past this area the pipe goes downhill. They knew the leak was in the downhill area and the leak detector guy said "gas doesn't go downhill." So he never did anything, drove away and billed for the visit.

Eventually, after long painful discussions about what to do next, I reminded my neighbor that this same plumber installed a compression union down hill a few years ago when he had a previous leak. The plumbers and my neighbor finally agreed to act on my hunch and dug up this existing compression fitting and found that it was leaking.

The reason why this compression fitting had failed was that at this point, the 2" water line starts a large bend where the pipe must turn 180 degrees down the driveway. We call this area of driveway "the switchback." If you zoom in on the picture you should be able to see that the pipes don't exactly line up in the compression fitting. There is great pressure of the pipe and the water in this fitting.

This got me to wondering if there was a better solution to this issue.

What I found was confusing and contradictory. The first solution would be to use a the PVC cement bond, but this plumber said that would be weak and didn't want to do it. I found references to a "stiffener" that could be added into the ends of the pipe when using a compression fitting but when I looked online, all I could find were the stainless steel stiffeners for other types of plastic pipe and none said specifically PVC. The last solution I found was the larger PVC threaded unions but those would still have to be cemented into place.

Has anyone seen or used a "stiffener" inside a PVC pipe in conjunction with a PVC compression fitting? Should I be looking at something else?

By the way, the plumbers charge $500 for each time they dig up and install one of these ball valves, so my neighbor had to install about 3 or 4 of them and that cost builds quickly. The ball valves were installed to narrow down the location of the leak the last time it happened.

Well, that sounds like a pigs breakfast, and not one of your making! Sorry to hear it.

I think that your neighbor should consider finding a different plumber. I also think that the plumber should not be using compression fittings underground. Some countries do bury certain special kinds of compression fittings, but they use different materials, and not PVC. Around here, buried compression fittings for water is against code, for several reasons. I think, e.g. the couplings loosen over time, the seals can act as a siphon (Venturi) to suck in air, water, and microbes from the soil.

Not to be critical, but I do see a few issues with the way the pipe was laid.

• Every time water starts or stops in the pipe, you are going to have a small water hammer and pipe motion.
• That is a pretty tight bend for 2" PVC, and in my experience, pretty much any fitting you try to put there is going to have a hard time, and fail.
• If the "switchback" is on a slope, every time the water flow stops or starts, the pipe is also going to try to work its way downhill, and that will stretch and move the pipe over time, (straining the couplings), and has to be accounted for.

Possible fixes:

Do as @4570Man suggests, retrench, use new pipe, and put in a straight run, with concrete at the elbows to anchor the pipe. If your local code and utility permit it, I would certainly consider one run of polyethylene pipe, no fittings, until it was inside the house. Regardless of the type of pipe, when you lay the pipe in the trench, try to have it meander a little to allow for expansion and contraction of the pipe compared to the soil. It will happen. Do use compacted trench sand.

You can also heat PVC and bend it. I would use the longest possible stick (20'), and get all of the couplings out of the curve, but I think that that tight a curve is going to be a problem in straight PVC. You could go track down some 22.5 degree bends and work your way around the curve with straight sections plus 22.5s, but I will warn you that the size is uncommon, and priced accordingly, and the water flowing in the pipe is going to flex each coupling every time the water starts and stops, so a long way from ideal in my book.

No, you should not try to use a "stiffener". If you need stronger pipe change up from schedule 40 to 80 or 120, but the stronger pipe is going to resist the bend even harder, putting even more strain on the fittings.

Brass fittings buried should have waterproofing applied to them, e.g. self sealing silicone tape to prevent below grade corrosion of the brass that can be fairly rapid in some soils.

All the best,

Peter

 

[AnotherBueller]

Have you thought about asking you water company how they repair water main brakes and do that?