Looking for a flood zone?
Flood zone is decided parcel by parcel, so there is no Illinois answer and no city answer either. Look up the specific address and you get the flood zone alongside everything on these pages.
AddisonArlington HeightsAuroraBartlettBellevilleBerwynBloomingtonBolingbrookBuffalo GroveCalumet CityCarol StreamCarpentersvilleChampaignChicagoCiceroCrystal LakeDecaturDeKalbDes PlainesDowners GroveElginElmhurstEvanstonGlenviewHanover ParkHoffman EstatesJolietLombardMolineMount ProspectNapervilleNormalOak LawnOrland ParkPalatinePark RidgePeoriaPlainfieldQuincyRock IslandRockfordRomeovilleSchaumburgSkokieSpringfieldStreamwoodTinley ParkUrbanaWaukeganWheatonWheeling