I assume you're caching by a road? How cold does it get? How many days exactly?
In the utah desert, we used to cache a lot in the winter, but with larger groups and larger water needs. What we found to work was to cache in LARGE containers because they take longer to freeze through. What was implemented were those insulated orange gatorade coolers (perhaps 20 gallons). Don't screw the cap on much at all because it freezes. The spout freezes too but you can just open the top and break the ice.
Five gallon jugs would sometimes freeze solid. Putting things on foam pads to insulate from the ground worked. So did covering the water, even putting the container in a garbage bag would help.
I guess the strategy of anticipating ice and dealing with it would work as well. We didn't like dealing with ice though.