How cold is cold, this fall we spent several days with temps in the mid-20s at night and 50s during the day. It just was not cold enough long enough to freeze any significant amount of water.
Fresh, grey and black tanks take a while to chill down. The pump, fresh water and drain lines to the sinks and the toilet are all inside the living space, usually behind or under cabinets, sinks and etc. The are warmed by the space heater we use for the living space.
When we do camp in sustained cold, we dry camp. We carry a seven gallon water jug for cooking. We use the CG wash house. It is not too much different than when we tent camp in the summer.