How does water supply enter into a pedestal house in cold climates?
Typically in an insulated chase, with heat tape. A more minimal install may just use heat tape and insulation without a chase, but it does not last well - but that's usually what you'll find under mobile homes that are not "on a foundation" in Maine, for example. A high-class operation will use internal "heat tape." A low end operation, or one with a gravity pressure water system (well higher than the house) may simply have a faucet they leave dripping all winter.

For a second home or cabin, the water may just be shut off for the winter. Drain everything, put some antifreeze in the toilets and sink traps.