This chapter's protection standard is based on the FIS for Cook County, Illinois.
(A) If a BFE is not available for a particular site, then the protection standard shall be according to the best existing data available from federal, state or other sources.
(B) When a party disagrees with the best available data, they shall submit a detailed engineering study needed to replace existing data with better data and submit it to IDNR/OWR and FEMA for review and consideration prior to any development of the site.
(C) The BFE for the floodplains of village shall be as delineated on the base flood profiles in the FIS of Cook County prepared by FEMA dated November 1, 2019 and such amendments to such study and maps as may be prepared from time to time.
(D) The BFE for the floodplains of those parts of unincorporated Cook County that are within the extraterritorial jurisdiction of the Village of Crestwood or that may be annexed into the Village of Crestwood shall be as delineated on the base flood profiles in the FIS of Cook County prepared by FEMA and dated November 1, 2019 and such amendments or revisions to such study and maps as may be prepared from time to time.
(E) The BFE for each floodplain delineated as an AH Zone or AO Zone shall be that elevation (or depth) delineated on the countywide FIRM of Cook panel number(s) 17031C0617K, 0636K, 0619K and 0707K dated November 1, 2019 and 17031C0637J 0638J, 0639J, and 0726J dated August 19, 2008 and such amendments or revisions to such study and maps as may be prepared from time to time.
(F) The BFE for each of the remaining floodplains delineated as an A Zone on the countywide FIRM of Cook County panel number(s) 17031C0617K, 0636K, 0619K and 0707K dated November 1, 2019 and 17031C0637J 0638J, 0639J, and 0726J dated August 19, 2008 shall be according to the best existing data available from federal, state or other sources. Should no other data exist, an engineering study must be financed by the applicant to determine BFEs.
(1) When no BFE exists, the BFE for a riverine floodplain shall be determined from an accepted hydraulic model, based on current industry standards.
(2) The flood flows used in the hydraulic models shall be obtained from an accepted hydrologic model, based on current industry standards, or by techniques presented in various publications prepared by the United States Geological Survey for estimating peak flood discharges.
(Ord. 2521, passed 9-19-2019)