This means that your gutters are most likely clogged. The build up of leaves, and debris can cause this. When there is a substantial amount of rain and your gutters are backed up, the water will begin to overflow. Your downspouts can also get clogged. If the water cannot flow out of the downspout, it will back up and overflow from you gutter. Clogged or leaky gutters are one of the biggest causes of basement leaks, mold and other foundation problems. A gutter cleaning can solve flooding. Cleaning them at least twice a year is highly recommended.