We need to resurface our driveway. Our lot slopes from front back.. Our driveway runs along the back of the house, perpendicular to the slope. As it is the run off is right along the foundation of our house. An old cement walkway is allowing water to run in along the foundation. We want to reverse the slope of the driveway toward the back. Easy enough.. accept that it has to integrate with an alley which runs along the side of the house. How do we join our driveway with this downward slope if we change it to move water along the other side? Thanks.