Removed galvanized service line and pull through poly?

[Dgeist]

This is a follow to my post about materials and techniques for new residential water service. My current service is galvanized, laid in 1970 but exposed and re-buried a couple years ago, and is about 20-30 inches deep in the front yard (50' or so).

I know I could dig it out, but clay in my area is a bear to dig in by hand and even if I'm going to leave the current pipe in there, I still have to dig out both ends. Directional boring would add just over a grand to the cost of the work, but I'm wondering if I could possibly disconnect both ends of the pipe and just "pull it through" into the basement with either the new poly line attached or a rope to which I'd attach the poly line. Obviously some assistance with the sledge hammer and come-along would be required, but if I could do it, I'd save near $1000 and not have to dig up the yard.

The other alternative is to cut off both ends, and mechanically trench right next to it (or over it if the line is deep enough) and just deal with the repairs to the landscape, which is mostly just turf grass in the affected area with the exception of crossing under my front sidewalk.

Has anyone tried or seen my 'poor man's directional boring" attempted? Am I just coming up with elaborate ways to solve a simple problem?

Dan

 

[Jadnashua]

The friction, especially with the couplings in there, on trying to pull a 50' pipe through the ground is going to be quite a bit...if the pipe is at all compromised, and at 50-years old, probably is, it probably wouldn't make it and I doubt you'd be able to do it with any manual device. I haven't had to deal with any of the trenching or drilling scenarios...can't help there.

 

[Sponsor]

 

[Dgeist]

Thanks, Jim. I suspected as much, especially with as much friction as would be found in old galvanized pipe and possibly some external corrosion.

Assuming I leave the pipe in place and just cut off both ends once I trench down to it, do I need to do anything special with respect to preventing contact between it and a new poly line? I was thinking of possibly putting in some larger PVC as a protection sleeve first for protection and to make it more serviceable later. Is that common practice? If I terminate that sleeve in my basement, would I need to use anything more than foam or silicone caulking to seal that penetration?

Dan

 

[Terry]

You could consider digging a hole in the middle and boring both directions.
I've bored under driveways before.
Pulling your pipe in clay?

 

[Dgeist]

The more I look at it, I think a simple trench is the most cost-effective, whether hand dug or with a 24" "pull-behind" trencher (I have no frost line in my area, so it's at 24"). I'll have to do a hybrid "pull" of some kind under the sidewalk, so pulling out the galvanized pipe to help with that may be a good plan after all, but pulling anything into the structure sounds like it might be a problem waiting to happen. I really don't want to DIG under the sidewalk any more than boring a pilot hole, mostly for fear of disrupting it structurally. As for the rest of the run, I'm guessing if I can get CLOSE to the pipe's level and apply some torque, it won't be too terribly hard to pry out.

If you've ever looked at the soil in southeast's piedmont region, you'd know what I mean about the clay: http://www.nrcs.usda.gov/wps/portal/nrcs/detail/ga/soils/?cid=nrcs144p2_021871

It's drains poorly, is heavy and clumps. It gets hard when its dry and it gets really sticky and starts to smell bad if it's left wet. Interesting to dig in

Dan

 

[Reach4]

Different places have different requirements about pipe penetrating into a basement. I don't find it now, but I remember a post that said his area required switching to copper some distance before the basement wall.

I have a friend with a new house where the copper water line comes through galvanized The galvanized drips. Look to seal the outside part of your pipes well against water rather than trying to seal from inside. 3M Fast Cure 4200 Polyurethane Adhesive/Sealant looks interesting, tho I have had no experience with it. Fast is relative. http://multimedia.3m.com/mws/media/385584O/3mtm-marine-adhesives-and-sealants-brochure.pdf

I suggest laying down tarps, cardboard etc to hold the dirt. Clay laying on grass is bad for the grass. Clay lumps mixed with topsoil makes for bare spots.

Either separate topsoil vs clay, or discard part of what you dig and top up with topsoil. The trench will settle with time. You can hasten that by flooding the restored clay for a day or two before putting the topsoil into place. Some pound the restored dirt with a sledgehammer to compact the dirt.

Commercial diggers will usually just heap the clay mix on top. Avoid that.

 

[Jadnashua]

Most raw clay swells (sometimes a lot) when it gets wet. You don't have to do anything to the old line, you can leave it there.

 

[Dgeist]

Thanks, Reach. Sealing is something I'd definitely do at EVERY level (probably hydraulic cement against anything touching the foundation and something like what you mentioned anywhere inside. I'll check with my city on any stipulations of where and what can penetrate the foundation.

 

[Cacher_Chick]

I have seen guys pull pipe through using a chain off the backhoe, but they were putting in copper, and the soil was not clay.

 

[hj]

For A 50' line I would use copper rather than poly, but that is just a personal preference based on many years of experience.