I have four window wells in my basement.
All have drains and there is no water problem.
But one of the wells fill with mud and I can't see where it comes from?

Bob K.

How far above the ground is the top of the window well? Can rain water be overflowing the top and bringing in mud?

Harold's asking for more details. Any loose dirt around the window well?
Could it be backing up from the drain? Can you give us more details? Back to you. Tom