Deb
I am curious how it is that these lines freeze every year and yet do not break? What kind of pipe?
I live in a cold climate too and one of the things I work on all the time is trying to come up with better and easier ways for people to winterize their "cabins".
I don't think I would be for draining anything back into the well. Not quite sure I follow the "dry hydrant" idea...Okay, you install a hydrant in the normal way near the well head somewhere. Power to pump is off, pressure tank, WH, house lines drained. Is the plan to open hydrant, hook a hose to the hydrant, a drill pump, and a hose back to the well head, open faucets in house, turn on drill pump, and pump water from the house main line up through the hydrant and back into the well head? This should work IF there are no bellies or sags in the pipe under the house where you start sucking air. Any water trapped in lower spots will stay there and can freeze. And if the drill pump has the ability to lift the water. A drill pump has a very limited ability to lift water--that is what keeps it from draining the well. If a drill pump could lift the water from a 190' well, we wouldn't put in expensive 220 v 1-1/2+ hp pumps way down there in the ground ;-) Also, I don't know why it would be called a dry hydrant since it wouldn't really be.
Hube's idea is good, but like he said, only if there are no nineties or sharp bends.
No access to your crawl space? Seen crawl spaces that I wondered why they had an access since no one who weighted more than 80#s could possibly get down there, but never a crawl space with no access. Don't think that you should tear up your bathroom floor either, most people do not have access holes in their bathroom floors. How about a closet, under a staircase, a pantry? I find that lines under homes freeze when the crawl space is not tight--you go down there in the dark and can see NO light, which means no place for cold air to come in. The ground actually puts out quite a bit of heat. I don't believe that I have ever gone into a crawl space that is completely tight and repaired freeze breaks.....
Deb
The Pipewench