450' water line

[frank29]

I need to replace a problematic water line. Existing diameter (1-1/2") provides plenty of volume & pressure. Problem is the constant leaks, at least a dozen over the past 20 years. The existing blue colored line is a "bell & socket" design: each length is 20', one end has an enlarged end which has a rubber O-ring, the other end just slid into the enlarged end. It has the same diameter as PVC, in fact the end coming through my basement wall is reduced using standard PVC fittings.

Some of the leaks have an understandable cause such as trees roots growing next to a joint. Other leaks are mystery leaks worthy of the X-Files. The convuluted path the line took contributed to this. Now that my property is developed, the new line will follow the driveway and hopefully avoid some of my past problems.

The last time I had a leak I promised myself, as I sat in a muddy trench, that the next leak would prompt a compete replacement. That time is now.

I am undecided between 20' lengths of PVC and longer lengths of coiled poly pipe. Any strong opinions on this?

As far as poly pipe is concerned, there seem to be a lot of options (at least compared to PVC). Any thoughts on particular brands or connection methods? Using a barbed insert into either end of a pipe and tightening with clamps seems to be inferior to PVC solvent welded connections?

Thanks for any help.

 

[texasjohn]

I think it would be instructive to do an analysis of the CAUSE of each of the prior failures. The point is, poly pipe is flexible and a tree root will push against it, deform it, but not likely BREAK or shatter it such as can happen with PVC.

On the other hand, poly is perhaps more susceptible to a puncture from a rock or very sharp object.

Look into pulling with a subsoiler whichever type of pipe you end up using. I've pulled poly black coil and it works well... there are reports on TBN that others have pulled links of PVC after they are joined together and dried.

So, I'd try to do a $ cost analysis, installation time analysis, installation equipment cost, likely reliability analysis given your conditions of soil and leak history..... and, hopefully, an answer will emerge.

 

[marimus]

Ive pulled in several thousand feet of poly pipe using my subsoiler. Through clay, loam, rocks and more. So far its never leaked, and it sure is quick to install.

PVC would have taken days and days to install, but at least its more expensive

Cran

 

[EddieWalker]

I The existing blue colored line is a "bell & socket" design: each length is 20', one end has an enlarged end which has a rubber O-ring, the other end just slid into the enlarged end.

This is the good stuff and probably something most people have never seen. it's very expensive and about as good as it gets for water lines. Like anything else, if it's not installed properly, it will fail. I'm at a loss to why it's leaking, so please be more specific. My guess is it wasn't installed properly. You don't bend it, you don't put glue joints on it and you must be sure to block it at the ends of a run. It will move. It's designed to move. The important thing is to limit it's movement so it works as it's designed.

Your first choice for a new line should be the blue, slip jointed pipe. It's either C-900 or C-909. It's not easy to install, but it's not rocket science either.

Next would be Schedule 40 PVC. The problem with PVC isn't the wall thickness. Schedule 80 is stronger, but it's so much overkill that there's no advantage to it in underground applications. Schedule 80 is mostly used for above ground use. The weekness in PVC is the glue. It doesn't actuall glue the pieces together, but sort of welds them together chemically with primer and then glue. This gives you a very solid seal, but there's no flex in it. If you have clay soils, or soil that moves, then PVC will be stretched to the breaking point. My experience isn't all that great, but I've see these breaks and it's either the middle of the pipe, or the joint pulls apart. When it's the joint, you can see part of the plastic pipe actually breaks away.

Black Poly comes in several thickness's and lengths. The thicker is better and your only real option. I forget the ratings as it's not something I'd ever use. Lots of guys have it on there homes, especially for lines running from a well to the house. It seems to last for them, so it's OK in some areas.

My main issue with it is the City of Tyler used it in part of the city for their water lines. I don't know how much of it is in the ground, but it's not working out. They have crews that work 24/7 fixing leaks. It's so common, that's all those guys do. I know this first hand as I had one of those homes that had a line break. It took them a few hours to get there as they were working on another leak. We chated while they fixed it and really drove the point home to me at how bad it is. The city would replace it, but with all that they have in the ground, it's cheaper to keep the crews out working on patching it.

Before you start on this, you really should go talk to somebody at your water district and find out what works, and what doesn't. They live for this stuff and go to meetings all the time on it. Plumbers might be helpful, but nowhere nearly as knowledgable as your water district.

Soil, distance, depth, preasure and money need to be figured into what to use and how to install it.

Good luck,
Eddie

 

[mjncad]

I would put the pipe regardless of type in a bed of pea gravel or squeegee. it allows for subtle movements in the pipe and if you need to dig up a portion to repair it, it sure beats getting compacted clay soil off the pipe. Put a 3" to 6" bed of gravel down first, then lay in the pipe, then put at least another 6" of gravel in before you cover it up with 6" to 12" of native earth. I also like to put detectable marking tape above the pipe before it gets covered up by native earth.

I know this adds to the cost; but it's easier to do it now while the trench is open than later.

 

[TedLaRue]

EddieWalker and mjncad posted replies while I was typing mine, and I mostly agree with both of their posts. Considering EddieWalker's post describing problems with polyethylene (PE), and my post below, it seems that PVC may be the way to go. And mjncad's suggestion of backfilling with pea gravel is an excellent idea, but could be pretty expensive for your 450' line. If your trench is 12" wide and you cover the pipe with 6" of pea gravel, you'll need more than 8 cubic yards of pea gravel (about 11 tons). Check your local source to see if that's affordable. Also consider whether you have the means to distribute the gravel. Of course if your trench is only 6" wide, you'd need only half that amount.

Around here, a 250' roll of 125psi 1-1/2" PE pipe runs around $180 as of August, 2007. That's about 72 cents per foot.

A 20' long stick of schedule 40 PVC glue-type bell end runs about $7 which is about 35 cents/foot. I don't have a price on PVC with the o-ring type bells.

Check your local suppliers for prices in your area!

You have a 450' run. Assuming the prices I gave above are correct, the difference in price for the pipe alone would be $166 in favor of PVC. I think that difference would be about the same or perhaps even greater if you factor in the cost for fittings for the PE and the cost of primer and glue (if any) for the PVC. So it comes down to how much your time is worth. Gluing or driving together 22 joints in the PVC....that's about $7.57 per joint for your labor. If you can do a joint in 15 minutes, that's like paying yourself $30/hour. And that's assuming that man-handling the 250' rolls of PE takes no time at all.

I doubt if you have a subsoiler that can lay 1-1/2" PE line, but if you did, that would probably be the way to go as marimus suggested.

 

[TedLaRue]

Here's my experience:

I put in a 600' water line using 1-1/2" polyethylene (PE) black plastic pipe with only one joint. For that joint I used a brass barbed coupling and triple clamped it (six stainless steel clamps). Then I "marked" the joint by burying four or five flattened aluminum cans just a few inches underground above the joint. I also put in a T-post to temporarily mark the spot (twelve years ago, and the post is still there). By the way, when you clamp PE, it's wise to go back the next day and tighten the clamps again. They also make a coupler that has a stainless steel sleeve that fits up inside the pipe, with a heavy split brass clamp that goes around the outside of the pipe and is tightened with a couple of bolts. That's a much more secure coupling, but they aren't cheap. I'd have used one, but I didn't know about them at the time I laid the line.

Then I put in an additional 120' of 1-1/2" line using 20' sticks of PVC pipe with a bell on one end. I glued that pipe using primer and then the glue. I backfilled the first few inches of that by hand, also.

My water pressure is 70psi which is quite high, but I've had no leaks on either part of the line. I put the line 36" deep and backfilled the first few inches by hand to avoid large rocks up against the pipe.

If I had to do it again, I would probably go with PVC.

I used PVC for the 120' stretch because I didn't want to buy a 250' roll of PE for a 120' stretch. The PE may be quicker, but costs more and the pipe is softer. The PVC is cheaper but the pipe is brittle, and if you glue the joints, it's somewhat time consuming. The o-ring joints are pretty quick (if you lubricate the o-rings with soap), and they allow for some movement of the pipe. I've used them for drain pipes, but I'm still not convinced that the o-ring joints are as good as glued joints for pressurized water lines.

 

[marimus]

Wow, I can't believe how cheap PVC is for you guys!

Over here, pvc is several times the price of PE pipe (of any pressure rating).
We use PE for town water supplies, but there is never any leak issues with it. They butt join the pipes using a special tool that heats the pipes and then clamps the ends together.

The PE I uses is of "rural" designation, which is rated to 120psi and is marked with a green stripe. Higher pressure pipes have a blue, or yellow stripe for the highest rated.

Cran

 

[frank29]

.......if it's not installed properly, it will fail. I'm at a loss to why it's leaking, so please be more specific. My guess is it wasn't installed properly......

I'm sure that was a big part of my problem, at least early on. Shortly after the intial install the first slip joint (20' from the meter) started leaking. I cut out a section and solvent welded a piece of PVC in. A week or two later the secon slip joint (40' from meter) started leaking. Same fix, except this time I noticed the meter had been pushed back by the pressure causing the first two joints to leak....luckly the next joint (60' from meter) had enough friction through 60' of ground contact to stop pushing the meter.

Other understandably leaks were caused by tree roots.....the line's original (current) path was dictated by my ability to navigate a trencher through my undeveloped densly wooded lot. Bad move. A good part of the line runs through areas that are still densly wooded, hense, tree roots problems. The replacement line will run alongside the driveway and greatly reduce this problem.

The rest of my problems are just plain wierd. For example, last summer I had two tees start to leak. These tees had never been used. In case I every wanted to add another spigot, I put a tee in line with a short capped stub. In both places I put a meter box & cover. I don't know if they started leaking at the same time or not, all I know is I was searching for a leak and found both problems at the same time. The leaks were at the foot of the tee....I probably not describing this correctly: where the tee crosses forming a perpendicular crossing, the PVC was cracked! When I saw this I called a plumber, he saw no reason for such a thing, the line is straight and not in a bind.

My neighbors have no problems. I know I caused some of the early on problems, maybe I caused all the problems; I just know I want a new line running through a cleared area and the idea of minimizing joints sounds appealing.

Thanks to all for the input.

 

[LoneCowboy]

PVC, PVC, PVC

I agree with Eddie Walker, that jointed pipe doesn't leak unless it's installed incorrectly.

PVC freezes and shatters, and PE won't
BUT
PVC has wayyyyyy better flow characteristics and will not get eaten by tree roots, where poly will (it gets squeezed, impossible to find until it finally breaks, can take years)

Prime every joint, gray glue, twist as you put it together. The bell faces the water source. (you'll see it, it's not a hard step facing the water if you do it that way)
PVC lasts 50+ years, poly lasts about 20.
Just bury the PVC 1' below your frost line., won't be a problem.