Since there are no pictures, I will assume the source of the water is the downspout and not drainage from the yard or something else. Resetting the metal window well flush with the foundation wall will not solve your problem. You need to get the water away from the foundation. The best way to do this is to divert the downspout water to the street. This means digging a trench and laying 4" drainage pipe under the sidewalk and through the curb, allowing the water to drain into the street. (There are contractors who will cut the concrete for you.) Alternatively, you could pipe the water to a catch basin away from the foundation. Ideally, the window well should have a drain pipe starting at about 4" below the window down to the weeping tile along the base of the foundation (6 to 7 feet down). But not many builders do this. They just put a few inches of gravel in the bottom of the well and hope you don't notice until after the warranty period.
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