Spillover

Over the top of the wall:
Water entering at the top of the wall, between the concrete and wooden sill-plate, is due to one of 2 things: The soil grade has been built up outside the home, higher than the concrete. Homeowners, in their efforts to keep water away from the foundation, build the dirt level higher than the concrete wall, ironically creating a seepage problem through the below grade brick or siding.

The surest way to verify which of these two "spillover" problems you have is to water test by running a hose on the ground on a dry day. If water comes in, it is a below-grade problem.  If water does not come in, then it is an above grade problem that will require caulking, tuckpointing or possibly roofing repairs.

Sometimes there is an above grade penetration of water, due to a caulking or tuckpointing issue. Any water that penetrates the veneer of the house will run down the back side of the siding and appear at the sill-plate juncture in the basement.

The basement is a valuable part of your home and is designed to be dry, usable space, whether as a finished recreation room, a workshop, or simply a safe storage area. Once a leak occurs however, its usefulness and value is very limited - fortunately permanent solutions are available for all seepage problems.