Very long water line...

[Valveman]

Poly pipe will expand or contract by 1" for every 10 degree temp change for every 100' of pipe. If you have 20 degree change in ground temp between summer and winter, 2500' of pipe will expand and contract by 50". Be sure and fuse weld the connections as it will pull apart from compression couplings. And concrete thrust block or anchor the ends of the line.

In summer the pipe expands 50" and pushes up in the ditch. Rain will pack the dirt under the pipe. Then during winter when the pipe contracts 50", it will pull loose from the connections.

PVC pipe doesn't expand or contract nearly as much, and gasket fittings leave some room for expanding and contracting.

 

[Water Monster]

Thank you for the comments. One more question please...

We plan to trench using a bobcat with rented attachment which I think will leave a ditch 5" - 6" wide. Is 2" pipe flexible enough for us to drop this in as we go along and lift the end out to glue on new piece? Any other thoughts or suggestions would be appreciated. Will probably only install 500-750' at a time since run is so long.

 

[Sponsor]

 

[Water Monster]

Thank you, Valveman...I just noticed your post on the new page. What about primer/glue for the 2" PVC? This is what suppliers here are suggesting?

 

[Texas Wellman]

I always use the Weldon brand for Glue and Primer with no problems. Glue everything on top and then kick it in the ditch, it will flex. Pressure test before burying.

 

[Texas Wellman]

BTW: See if you can find a supplier to sell you the pipe in a "lift". A lift of 2" is 2800 ft. You should be able to get a good deal and perhaps have some leftover to sell etc.

 

[Greenmonster123]

I would suggest using gasket end pipe not glue end pipe.

 

[Boycedrilling]

You will have a hard time finding 2" gasketed pvc pipe and it would probably cost 50% more than glue type PVC. However in that long of a continuous, straight line run of pipe, I would recommend one or two gasketed expansion fittings. It does get hot in Georgia. We used to own farm ground at Cartersville, and I have a sister that used to live outside of Ringgold.

I only use Weldon brand PVC glue and solvent. They are other brands that are half as expensive. But I will not use them in pressure applications. However PVC electrical conduit is another story. Do not use one of their fast setting glues like 721 or Wet-RDry. I use P70 primer, either clear or purple. Then I use 705 glue. Follow Weldon's instructions. I believe they have a video on their website. They actually have classes now that instruct installers in selecting the proper solvent and glue and the proper methods of use. I have them scheduled to teach a class at a regional groundwater expo.

 

[Craigpump]

I'm not a fan of glued pipe.

You might want to consider 2" Certalok PVC. It has an O ring and a plastic spline. Very simple & fast with no potential of contamination from solvents.

 

[Greenmonster123]

You will have a hard time finding 2" gasketed pvc pipe and it would probably cost 50% more than glue type PVC.

That is not true, gasket pipe is within 5% of glue pipe. You probably won't be able to walk in to Home Depot and find 2500' of it but it is likely available from any reputable supply with some notice.

 

[Texas Wellman]

Just curious on why y'all don't like glued pipe? If done properly it will not come apart at the joints, ever. Yes, it can break but not at the joints. Never seen gasketed PVC in small sizes.

 

[Valveman]

Fro short runs, (200'-300') glue pipe is fine. But for long runs gaskets let the pipe expand and contract without crawling out of the ditch because of temp changes. Needs to be bedded with sand correctly though.

 

[Greenmonster123]

Just curious on why y'all don't like glued pipe? If done properly it will not come apart at the joints, ever. Yes, it can break but not at the joints. Never seen gasketed PVC in small sizes.

I have installed tonsof gasket pipe 2"-6" in the past few years for irrigation systems. Gasket pipe installs probably 2 times as fast because you are not having to hold the joints to wait for the glue to set. And as others have said it can expand and contract within the joint.

 

[Water Monster]

I'm a little concerned about the glue. This is the first I've heard about a gasket pipe. I planned to use ball valves periodically to isolate future problems or leaks. Could we accomplish the same thing with this...500' or 1000' of glued pipe and then a compression type ball valve? Could a fitting provide necessary flexibility for expansion and contraction?

 

[Valveman]

I have a 12 year old system with 7200' of 1.5" poly that came in 500' rolls. I have had to dig up every compression fitting and butt fuse the pipe. Even the threaded ball valves I installed have tree roots spiraling down the threads into the valve until they leak. I made some S turns, butt fused the pipe, concrete anchored the ends and fittings, and now I am salting the threaded fittings for the tree roots. I hope this is the last fix as I am getting too old to be digging so much. Just my 2 cents.

 

[Reach4]

http://www.hdpe.ca/wp-content/uploads/2016/03/tr-21_thermal_expansion_contraction_plastic_pipe.pdf is a paper on plastic pipe thermal expansion. Not a real easy read.

 

[Water Monster]

I did not think of roots...plan to trench on Monday and up a dirt road and very close to tree line. Thought that I would keep the trench closer to the trees than the road? Road has mild traffic, maybe 25 cars a day, and most of trench would go in drainage ditch that is less than a foot deep in most areas.

I spoke with local plumber since initial post and he recommends 1.5" poly line. I would certainly be easier for me and HD Supply sells some very nice compression ball valves that look like something a municipality would provide. In the event of inadequate pressure could one of Valveman's products work here? I would like to have serious pressure at the property and now thinking a total of three frost proof hydrants will be installed.

 

[Craigpump]

Your plumber is still looking to install a booster system at some point. Do the job right the first time and be done with it.

Like the Fram oil filter guy used to say "pay me now, or pay me later"

 

[Water Monster]

Ok...if we need to regulate pressure then with 2" pipe how is this best accomplished. Someone suggested that the regulator should go immediately after the tap at the street? Does this make sense? I thought that I would place regulator at the end of the 2500' run and before entrance to the property before splitting lines to hydrants.

 

[Greenmonster123]

Ok...if we need to regulate pressure then with 2" pipe how is this best accomplished. Someone suggested that the regulator should go immediately after the tap at the street? Does this make sense? I thought that I would place regulator at the end of the 2500' run and before entrance to the property before splitting lines to hydrants.

What is your incoming pressure and what do you want to reduce it to?

 

[Texas Wellman]

I'm not sure thermal expansion should be much of an issue in GA. I don't imagine it freezes much.

You only need one ball valve at the front and one at the back.