I doubt that there is much you can do because you can't easily access the buried line. The only thing I can suggest is that it is more likely that any freezing would have occurred near where the hose enters the ground or leaves it. If that is the case, a gently applied hair dryer might free things up.

I would also be concerned over the long term about getting my potable water from a hose buried in the ground, from a health perspective. Do you live somewhere that has no plumbing supply codes?

Kudzu,

That 'black' hose is probably alkathene and is/was approved for potable supply, at least where I used to live (NZ/Australia) - for a while it was even used in houses in walls etc like Pex is now. I doubt it's a code issue, although if it wasn't buried deep enough that could be. -30 is pretty intense, though. Must be Canada, especially since they said Celsius.

In a rural area, it's very common. Mostly it's for water troughs etc in my experience, but for a long run from a well to house, say, it's understandable. Copper might not be practical, or it might just be too expensive.

Obviously it needs to be deeper in original poster's case, but like you said, not too much to do now....unless...

I know this is probably a long shot, but if there was a way of feeding hot water back down the line or perhaps heating tape on a copper section might heat it far enough back....?

I agree the freezing point is likely to be the shallow points. Chances are the pipe's unharmed if it's in the ground provided it's not been physically cut by frost heave or vehicles etc...it's pretty flexible.

My guess.. lack of snow.

Snow insulates the ground from the really cold weather. No snow allows the cold to penetrate the ground deeper. My second guess is that you have black polyethylene water line buried. It's very common to use this material in private water systems, especially in long runs from one building to another or from the well to the building.

The problem with this type of pipe is that you cannot apply heat to it effectively because it will deform or melt if the temp gets too hot. I agree that your problem is likely quite close to one of the buildings. If the outbuilding where the pump is has heat in it, then the heat is likely just enough to keep the pump and pressure tank from freezing.

If so, my third guess is that this building is where the problem is. You need to go to Home Depot's electrical aisle and buy a heating cable and a roll of black electrical tape. These cables come in various lengths and are usually orange in colour. You will have to wrap it around the plastic pipe tightly starting where the pipe leaves the building. Use the electrical tape to secure the end of the cable that is furthest from the plug, to the pipe and then continue wrapping until you have used up the entire length.

Use more electrical tape to secure the heating cable. If you have some old blankets around, wrap them around the heating cable to help hold the heat in. Plug in the heating cable and just leave it.

Go in the house and partially open a tap and leave it open. Make sure the drain is open. The idea here is to gently heat the pipe and the water that is in the pipe. If the freeze up is close to the building, the warmed water should thaw it. If it thaws even a little, water will begin to flow from the tap you opened. Warmer water will flow toward the frozen area and thaw it out very quickly. Let the water run for a good twenty minutes to get all the ice out of the line.

I would keep this heating cable in place and turned on. If you read the directions, you will find that these cables have a thermostat built into them where the orange meets the black. Tape this thermostat to the pipe.

Anyone capable of planning a wedding can certainly accomplish this task. Good luck and let us know how you made out.