There’s a simple reason why rain in the early new year months floods so many basements. There are a number of events that all come together like a perfect storm. The conditions are as follows;
1/. The ground outside is frozen. Perhaps from 4-16 inches depending on how cold it’s been. Right now in HRM it’s at least 8 inches minimum and more in some areas.
2/. There’s existing snow on the ground.
3/. Then you get mild temperatures and rain along with it.
4/. At this point, you know what’s going to happen. None of the rain is going to penetrate into the ground because it’s frozen. So it just lays there and builds up, and because it will always take the ” path of least resistance”, it drains and runs to the lowest places, running right along your foundation.
5/. The heat in your basement warms up the concrete wall and transfers some of that heat to the exterior, just slightly and enough to keep the frost away ever so slightly by about an inch from your foundation.
6/.When you get rain, and melting snow, this water runs along the top of the frozen ground until it hits your foundation……where there’s an inch of unfrozen ground and will enter in through any cracks or deficiencies in your foundation, around lower level windows, even sometimes over the top of the actual foundation wall.
7/. The results of any leaking into your basement will not be good. Sometimes even relatively healthy exterior drains can be overloaded. It’s like having a small stream or river pouring next to your wall. Then water enters from under the floor or hydrostatically between your floor and the concrete wall.
So in a perfect world, you would have the ground running away from the foundation and all downspouts as well, and ensure this has been done prior to Old Man Winter making his visit.