It hasn't rained here for about 3 1/2 days. Before that we got a ton of rain and I did a lot of driving. I noticed today that my back passenger side floorboard is completely soaked but the roads and car have been dry for about three days. I assume it's still wet from some type of leak from when I was driving 3 days prior in the rain but I would think it should be dry by now?

Has this happened to anyone else? I can't for the life of me figure out where the rain is coming from. The door seals seem dry, is there a plug or a place underneath where water can come in to these things?

The X5 is a 2002 4.4i

I am worried something will start rotting, the car already has an unpleasant smell from the moisture (almost a faint smell of fresh olives)

Also, FYI I am positive this is water. The residue is clear and has no smell at all so it's not some fluid leak.