My basement apt. got about 20 smelly gallons when the footwell drain clogged. I had been watching for leaves and stuff, but during a particularly hefty torrent, desbris got washed from the roof. Those crafty leaves clogged the drain just 30 minutes after I checked the drain. I was online 20 feet from the door, and felt water on my feet. When I opened the door a 4 inch tidal wave swept over the seepage and soaked my area rugs.
Sump pumps and a shop vac took care of most of the damage.
Compared to the folks in Pennsylvania and Delaware, I got off very light.