When homes are built close together on a slope, rainwater from the higher property can flow toward the lower home and collect near its foundation. Over time, this may saturate the soil and contribute to erosion, moisture intrusion, or foundation movement. What can you do? Start by talking with your neighbor about redirecting their downspouts toward the front or rear yard. Depending on the property, a properly designed drainage system may also help. A Grading / Drainage Contractor can evaluate the area and recommend the best way to move water safely away from both homes.