Flooding occurs when water from outside your structure rises and causes damage to your property and at least one other property. The source of the water can be an overflow of inland or tidal waters, the unusual and rapid accumulation or runoff of surface waters from any source or mudflow.
In simple terms, a flood is an excess of water on land that is normally dry, affecting two or more acres of land or two or more properties. For example, damage caused by a sewer backup is covered if the backup is a direct result of flooding. If the sewer backup is not caused directly by flooding, the damage is not covered.