View Full Version : Help thaw a frozen underground pipe

02-06-2004, 12:36 AM
A thread in which I hope to see unleashed the fabulous might of the SDMB.
Situation: My friend has a frozen pipe. It is 1-1/4" PVC. It is the supply from his well to his house. 45 feet out from the house, it has a 90 degree fitting. From there, it travels an unknown distance to meet a larger cast iron pipe, and the toal length from the fitting to the well is approximately 800 feet. The iron pipe is buried about eight feet down, and would be hard to get to through the frozen ground. The frozen pipe is under his newly paved driveway. Without thawing this pipe, there will be no well water 'til probably May.
An professional attempt was made to get a steam line to the ice, but the steam line could not get past the fitting. We are considering a hose to pump brine to the ice, but don't think the hose will pass the fitting, either. If the pipe were conductive, we would be using a welder, but it isn't.
Any ideas?

02-06-2004, 06:01 AM
If he can get to the pipe and be able to get it open he can thread a garden hose down it to the point where it is frozen and use hot water to melt the ice. Of course this won't work if he doesn't have any water at all.

02-06-2004, 06:44 AM
Living in Texas I don't have much experience with this sort of thing but Gramps used to be a plumber and IIRC he said when he lived up North he used some chemical that he poured into the water lines to thaw it. Kinda like anti-freeze after the fact. Flush the lines afterwards. Then find the area that's freezing up and take care of that.

This site sells something similar.

02-06-2004, 07:58 AM
So, the website claims it will thaw frozen supply lines from a well system. Pour a couple of liters into the water line at the primer screw atop the well pump. I'd probably try both ends simultaneously. It'd be nice to know the active chemicals involved.

Have you tried pouring salt into the line. I've heard that'd work sometimes.

good luck

02-06-2004, 08:10 AM
BTW Eight feet deep and it's frozen? Too damn cold for this cowboy...brrr

Forgive my ignorance in this situation, just trying to help. Throw out a few ideas and maybe bump your thread once or twice.

So, where you at...who ya helping, Santa maybe? :D

02-06-2004, 08:39 AM
Has it frozen before or is this the first year that this has been installed? The temperature has moderated considerably since the real cold snap on the East Coast, so if the frozen section is under an asphalt driveway, I wouldn't be surprised if solar radiation wasn't enough to thaw it eventually.

I'm not sure why you'd need to get the brine hose past the 90 degree bend -- couldn't you just flood the pipe with hot brine, wait a while, drain it and repeat?

Frost depth is never going to get down to 8 feet in Coastal Maine, so I'm guessing that the PVC pipe under the driveway is considerably less deep? Can you use this information to form a good guess as to where the block is? If you want wacky suggestions -- if your friend has any buddies who are pavers, they may be able to heat the asphalt driveway, either using a heated roller or an infrared patching techique (e.g. http://asphaltanimals.com/patching.htm#"Infrared%20Patching").

02-06-2004, 08:55 AM
The depth of the PVC pipe is unknown, but known to be shallower than the iron pipe. We are considering pumping a brine solution up the pipe, but suspect that the brine will not reach the ice unless we get the hose past the fitting. We also would have no way to know it it were having an effect. I'm thinking the main obstacle is that fitting. .
Thanks to all for the replies so far; keep that gray matter churning!

02-06-2004, 09:12 AM
I just talked to a nice fellow name Murray at the company that sells liqui-fire. Unfortunately, it looks like this is not a good application, as this product works by traveling throught the water to the ice. It's denser than water, so it settles to the low spot, but with the PVS known to be higher than the ion pipe, the stuff would settle before getting to the ice.
Good try, though...

02-06-2004, 09:32 AM
You seem certain that the pipe is frozen beneath the driveway. Could you drill a hole beside the driveway in the soil on either side with an auger (post hole digger) any size would probably do. I used to drill roadsides to setup street signs etc. (similar to saw used to cut frozen lake for fishing)? Here, (Texas) they can be rented for a few bucks a day.

They can drill at angles and have bits that can be added for depth. One on either side angled to the center. Insert a piece of PVC in the hole to near the bottom and fill it with a mixture of boiling anti-freeze/water. As the ground absorbs the mixture, keep filling the tube with more. It wouldn't refreeze and would ultimately increase the temperature of the surrounding soil.

Too bad about the liqui-fire...it'll help somebody that reads this maybe.

02-06-2004, 11:26 AM
I don't know where you live, but here (E. Hungary) the temperature very very occasionally goes down to -18 or so at the coldest, and the ground only freezes to a depth of max. 80 cm. I've been told by the plumber who helped me lay some pipes (I dug a 1-meter-deep trench to be on the safe side) that they have to bury the pipes two metres below ground in parts of Russia where it reaches -40.

Eight feet is even deeper than this, so unless you live in the north pole (or the pipes aren't buried as deep as you think) I doubt very much whether the section of pipe under your drive is frozen. Theoretically, covering the well should have prevented anything below a certain depth from freezing, so presumably your friend didn't do this, in which case surely it's only the end of the pipe exposed to the cold air that's frozen - i.e. the bit that connects it to the well...

If this is the case (and there is every chance I'm completely and utterly wrong about this), then maybe it's enough to pour hot water into the well until it thaws out the frozen end of the pipe.

02-06-2004, 01:32 PM
This won't help now, but next summer your friend should do one of two things: either dig up the pipe and re-bury it deeper, or dig up the pvc and replace it with metal piping with thaw wires attached. Then if the pipe freezes, one attaches a welder to the thaw leads and cures the problem.

02-07-2004, 12:05 AM
I really hate to think we're beaten here, but it looks pretty tough. To restate: chemical means are apparently out, as the frozen part is not at the lowest part of the system. Paving equpment: well, hmmm... I don't think that'll heat enough ground deep enough to thaw the whole thing. Ditto boiling water in an auger hole... (we could be talking about 40 feet of ice). trabi, the ice is 800 feet from the well.
The main obstacle still seems to be the 90 degree fitting. I'd like to pump in hot brine, but I don't think I can get it to the ice without getting the hose around that corner. It's a question of getting the solution physicallt to the problem from the hous end of the pipe.
Thanks to all for the respose so far; I know this is a tough one. (Miracle workers, this is your Big Chance.

02-07-2004, 12:49 AM
The pipe I'd choose for the situation described is called PEX or cross linked polyethylene. Used in Europe for decades, it is receiving increasing approval from code authorities in the US and may be available at a local plumbing and heating supply store. PEX is highly flexible, yet if the diameter chosen is close to the ID of the pipe with blockage, insertion shouldn't be difficult, and it is kink-resistant. To pass an elbow, I'd use a utility knife to bevel the leading edge to 45 and use a rotary motion when obstacles are encountered.
Good luck.

02-07-2004, 07:31 AM
My suggestion is to bypass the frozen section, then either reuse it when it thaws if not broken, or run a new line in the spring. If the pipe is frozen then it has a good shot of being cracked already.

You may be able to just run a hose from the well into your normal hose fitting, though there is usually a anti-backflow device on these. You will also have to run water continously when temps are below freezing to prevent the temp. line from freezing.

02-07-2004, 07:55 AM
hammerbach even if the ground is frozen you should be able to drill it. But forget that for now.
I know it's a long way, but why can't you get to the ice from the well end of the pipe?
Any water in the line would drain out when you disconnect from the pump and unless there are some hard turns in the line you should be able to get a line all the way without too much problem.
Maybe y'all have already tried this?

02-07-2004, 08:59 AM
I was thinking about how to get to the ice from the well. If you disconnected from the pump, drain out the water, then put an elbow pointing up, add enough pipe to ensure that it is higher than the rest of the line (esp. the frozen section).

You could then attach a large funnel of some sort and simply fill the line with brine. I haven't done the math but 800' x 1 1/2" shouldn't be that much fluid. It might take awhile to thaw...dunno about that. I guess you could do that from either end huh? hmm...I don't know, just a thought, maybe somebody'll pick it up and take it a few more steps. Where the hell is McGiver when you need him?

But hey, I'm still churning and bumpin' ;)

You got curious now, I hate an unsolved puzzle.

I hope I'm not becoming a nuisance. A few years ago my well went dry AND I had problems with the local community water coop. They wanted $2500 for a meter and I knew the SOB running the joint.
So, I hauled water for nearly three years (until the asshole retired from the water board) The meter price went back down to $1000 and I got on line.
Gonna drill me a new well this spring to water the garden and yard etc.
Point is...I know what a pain in the ass it is to be out of water for an extended length of time.
You don't fully appreciate the luxury of indoor plumbing 'til it's gone.

02-07-2004, 10:18 AM
Nobody here is being a nuisance. All ideas are much appreciated thank you.
I'd love to drain the well side of the pipe, but that's not where the pump is. The well is a few feet above the house, so it has a natural pressure head. I think he said the iron pipe is a 4" (it has not seen light of day since the mid '60s).
I think we're stuck on this one, and he'll have to haul water or dig up the pipe. Let that be a lesson to us all, to install our plumbing correctly.
And thanks,t-keela. Glad to have your input.

02-07-2004, 10:33 AM
Try something like a 1/2" dia. plastic tubing.
Tie the end to a plumber's metal drain snake, made like a tightly wound coil spring, and let the snake pull the tube thru the pipe. The snake will negotiate the fitting and take the tubing on down to the point of obstruction. Then feed hot water thru the tubing and proceed to thaw out the line.


02-07-2004, 10:41 AM
I'm still not convinced, if I could just see what we've got...

I'm usually pretty good at finding a way to get something done. Meanwhile, I've still got the poly tanks I used to haul water in. I've got a 550 gallon tank w/ a small jet pump that sits on top. I kept it in my greenhouse (reg. temp) and it was hooked up to the house.

I've also got a 210 gallon tank that fits in the bed of a truck. It' got a faucet at the bottom to attach a water hose. I'd fill it up every other day or so. When I got home I'd park the truck up the hill and attach the waterhose which ran downhill into the greenhouse. It'd gravity fill the big tank at night. Get up next morning and repeat if necessary.

Actually it worked pretty damned good for three years. AND cost a hell of lot less than the $2500 for a meter or twice that for a new well. I'm gonna drill my own this time. Gotta get me windmill...anybody? Gonna elevate a storage tank and irrigate w/ slow flow to the garden this summer. Maybe help keep the pond full also.

Tell your friend he can borrow my system if needed. Probably cheaper to build his own. ;)

Anyway, he may want to get by this way 'til it thaws. Good luck!

02-07-2004, 04:23 PM
They actually make a device called a ground thawing machine. It has an engine to drive a pump, and the heat from the engine goes into water/anti-freeze that is pumped through a series of flexible pipes. The pipes are laid on the ground where needed, and then covered with insulating blankets. Advertised to thaw 1 foot deep per 24 hours.

Your local equipment rental place might have one if you live in a decent sized town.

But as mentioned above, if the pipe was PVC and actually froze solid, it is likely that it has cracked.

02-07-2004, 05:22 PM
Here's a possiblity that you might try, if all these other suggestions don't work.

Attach a lead from an electric welder to the pipe at the well, and then attach the other lead to the pipe inside the house, and send a current thru it to melt the frozen water. If the pipe inside the house is PVC, then you need to attach the lead to a metal rod (something like an electrical grounding rod) that is inserted right into the water in the pipe. This won't work as well as it would with metal pipes, but just maybe the water itself would be conductive enough to complete the circuit. (Remember, it doesn't have to be a good conductor -- a poor conductor wastes electricity as heat, and that's just what we want here.) It's worth a try, at least.

I know it works for frozen metal pipes up here in Minnesota. I've had it done twice in 20 years. They disconnect my water meter, connect a lead there and the other one to a fire hydrant 4 houses away. Takes about 15-20 minutes of current to melt it. But that's entirely thru metal pipes. We don't have PVC pipes coming into the house -- they're not allowed here.

And you're probably right that it's freezing underneath the driveway. Mine freezes under the sidewalk in front, probably because the ground slopes down so that at that point the pipe is probably about 3 feet closer to the surface, and also the sidewalk is shoveled bare, while the rest of the ground is covered with 2-3 feet of snow providing additional insulation. Not sure what you could do for a permenant solution,though. My solution is to leave a faucet running just a bit during the times it's most likely to freeze. A bit wasteful of water, but much less expensive than having a welder out to thaw out the pipes.

02-08-2004, 12:16 PM
My plumber friend suggested something like his hydraulic snake which is a high pressure hose with a three orifice nozzle on the tiip. It is inserted in a clogged or stopped up pipe and threaded through to the clog of stoppatge. H high pressure pump then forces water through the jet nozzles at the tip. Cuts through roots, paper, seqage, and ice. Warm water would hasten the action.

You can even buy smaller & shorter versions to attach to the sink faucet to clean out sink drain lines up to something like ten to fifteen feet.


02-08-2004, 07:20 PM
I agree with the folks that say the pipe is probably cracked but here's what I'd do in this situation;

At a point within the house that offers a straight piece of pipe between me and the L, I would cut the pipe and thread a piece of nylon or teflon hose down the pipe until it stopped at the ice. If I thought that the ice was 40 or 60 feet from me I could compare that to the hose I've fed into the hole.

At the cut end of the pipe I would assemble a cheap, low volume pump, a 5 gallon bucket and a bucket heater. If you are not familiar with a bucket heater, it is similiar to a water heater element and is used to heat water in buckets for folks with crafts that demand water when it's cold outside like masons mixing mortar. It may have another name, but that's what we call 'em 'round 'ere.

Okay, arrange, attach and connect everything above to have the bucket heater heating water in the bucket while the pump sits in the bucket and pumps the hot water through the hose to the ice. The water melts the ice and is forced back to the cut end of the pipe.

If you can place the bucket under the cut the water will drain back into the bucket to be reheated and re-pumped. If putting the bucket beneath the cut is impossible you can dry fit some PVC fittings and pipe to the cut end to drain the water into the bucket. Just thread these fittings over the hose before it's attached to the pump. Make sure that any fittings you attach to the cut end are not glued so that you can seperate the connection to help with feeding the hose.

If you leave enough slack in the hose to allow for the total length of the ice blockage the hose can be pushed further into the pipe so that it is always directing the hot water right into the ice.

If the water drains too fast a P-trap can be fitted to the end of the cut to make the water fill the pipe before draining.

I'd start this job in the morning and monitor the process every now and again.

Good Luck!

02-08-2004, 11:40 PM
Thanks, Soisi... That's pretty much my suggestion as well. He says it's the third time with this pipe... Thanks to all, I'll be showing this thread to my friend Monday night.

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