The first step in preventing basement flooding is to understand how your basement is designed. The diagram to the right illustrates proper connections to the storm sewer and sanitary sewer system. The floor drain and waste from the bathrooms and kitchen are going out through the sanitary sewer and the sump pump and downspout are discharging to the storm sewer.
Storm water improperly discharged into a sanitary sewer can causing basements to flood into homes . The saintary sewer was designed to handle the sanitary waste only and does not have the capacity to handle the additional flow of storm water.
Submersible Sump Pump Installation
Find your sump pump. If the sump pump is connected to any other pipe in your home, it is most likely improperly connected. The drainage pipe from your sump pump should go from the pump directly outside your home at ground level. When a sump pump is re-plumbed to pump ground water to the yard or storm sewer, that water no longer takes up space in the sewer system.
A mechanical valve or a check valve will help prevent basement flooding. A check valve that closes automatically when flow through the sewer line reverses may be installed either outside the house or inside the basement, depending on the plumbing configuration of your home. These backflow devices are very effective in eliminating back-up. However, they can sometimes become clogged with debris and fail to close completely. When this happens, the valve will slow down the flow of sewage but not stop it completely. For this reason, the valve should be accessible for service and repair.
Redirecting your downspouts
Each downspout on a house can drain approximately 12 gallons of water per minute during a one-inch rainfall. Downspouts that connect directly to the sanitary sewer system increase the risk of sewer overflow and flooding. Disconnecting your downspout from the sanitary sewer and redirectly the flow is a simple process that can make a big difference. Redirecting a downspout into a rain barrel and with an elbow and extension into the yard.