Your drainage system will only need a sump pump if the weeping tile system installed lacks another gravity-fed drainage source. In certain areas, building codes also mandate the installation of sump pumps. Sump pumps are placed in a gravity-fed “pit.” Once the water reaches a certain level, the sump pump activates automatically, discharging the water outside the house to the exterior grade. Sump pumps are electrically powered and may require a battery backup. Heavy rainfall capable of cutting electrical power is the type of storm that fills the pit with water, necessitating the pump’s operation.