I have a tight, rough area of my house where water collects, and the foundation is not graded properly. There is no room to add soil to fix the grading issues. I thought I could install an exterior sump pump in the immediate area. However, freezing will be an issue considering this is in a northern, cold climate where winter temps routinely are below zero. Can an exterior pump be safely installed below the freeze line, and not be subject to freezing? How successful can such a pump operate to move water from say a small, 3'X5' area? Thank you.