I spent the winter in Bath PA at at campground before retiring in the spring. In a new at that time 2018 Forest river Grey wolf tt. It gets cold there, but not like where i am now in very northern MN.
That said, with a heated insulated fresh water hose connectected to the city water connection on the outside of the camper, other end going into a below ground enclosure.
I never had a frozen water hose, thats without dripping the water ever as that was a no no.
Wrapping the camper part with some reflexit insulation and using a good yet non evasive tape to secure it to the camper must have did its job at the camper end never freezing.
Securing insulation, tape, velcrow, no drill snaps, screw in snaps, lots of options to secure insulation over the connection part in or out type water connection.
A winter temp by the OP was never mentioned. That would be a big problem in some areas and nothing at all in others.
Its not hard to make a normal water hose heated and insulated.
Good hose, heat tape bought to length or some places sell it by the foot. Wrap that around the hose, wrap heavy duty tinfoil around that, then pipe insulation and done.
Leaving extra heat tape at each end to wrap around the connection points is even better.
The ends become the freezing weak spot.
The water is only one small step in fulltime winter camping.
The colder the area, the bigger and more steps.
