(1) “100-year floodplain” means any area of land designated as a flood hazard area with a one percent or greater chance of flooding each year by the Federal Emergency Management Agency under the National Flood Insurance Act of 1968 (42 U.S.C. Section 4001 et seq.). (2) “Flooding” means a general or temporary condition of partial or complete inundation of a dwelling caused by: (a) the overflow of inland or tidal waters; (b) the unusual and rapid accumulation of runoff or surface waters from any established water source such as a river, stream, or drainage ditch; or (c) excessive rainfall. (3) “Dwelling” means one or more rooms rented for use as a permanent residence under a single lease to one or more tenants.