If they pay attention to their gutters at all, homeowners generally do so only in autumn, even though poorly maintained drainage systems can do more harm in winter than at any other time of year. That's because when it's truly cold outside, water spilling over a clogged gutter doesn't collect into a pool—it freezes. If the freezing occurs over the surface of a driveway or walkway, merely maneuvering around your property becomes a treacherous proposition. By the same token, if gutter overflow freezes before it falls, icicles can form. While a few delicate icicles clinging to the eaves can be picturesque, large, pointy, and unstable chunks of ice can be life-threatening to anyone standing below, and the collective weight of many heavy icicles can actually tear gutters away from the home.