Slide left out during first snow

I would not put the water pump off till spring. Any water lines or components like pumps, faucets and valves that are not purged of water and filled or rinsed with potable antifreeze are at risk of splitting open when the water freezes. Low point drains do not necessarily drain all of the water out of everything. I blow out the lines with compressed air, then run antifreeze through them all, then blow the antifreeze out with compressed air to minimize after taste from the antifreeze in the spring. A gallon or two of RV antifreeze is a bargain compared to the cost of repairing any freeze damage.