You meant a pick, not a pike before, friend.
It would be much more difficult to dig a well in winter. I think, however, that it crosses the lines on realism vs worth taking the time to code. We don’t have snow in game yet and snow during winter would be a very easy source of water (as long as you have a fire, of course). So from a balance standpoint it’s not exactly game breaking considering the requirements… Also, it’s not like it stops you, it just takes a lot more effort.