Almost a third of its flood claims come from homeowners outside of high-risk areas. Many homeowners don't buy flood insurance because the believe they are covered under their homeowners policies. That's because they never bother to read the policy and probably bought it from a golfing buddy who never read one what they bought. The basic homeowners policy will cover you if a pipe bursts or a hurricane takes off your roof and rain blows into your home.
Extra coverage can cover for sewer backups.
Such policies cover 1. Overflow of inland or tidal waters. Unusual or rapid accumulation or run-off of surface waters from any source. Mudslides, caused by flooding, comparable to a river of liquid and flowing mud. Collapse or destabilization of land along the shore of a lake or other body of water, resulting from erosion, waves or currents exceeding normal, cyclical levels.