This chapter’s protection standard is the base flood. The best available base flood data are listed below. Whenever a party disagrees with the best available data, the party may finance the detailed engineering study needed to replace existing data with better data and submit it to the State Water Survey and the Federal Management Agency.
(A) The base flood elevation for the SFHAs of Mississippi River and Tribulaties 1 and 2 shall be as delineated on the 100-year flood profiles in the flood insurance study of the city prepared by the Federal Emergency Management Agency and dated November 1978.
(B) The base flood elevation for each SFHA delineated as an “AH Zone” or “AO Zone” shall be that elevation (or depth) delineated on the flood insurance rate map of the city.
(C) The base flood elevation for each of the remaining SFHAs delineated as an “A Zone” on the flood insurance rate map of the city shall be according to the best data available to the Illinois State Water Survey Flood Plain Information Repository. When no base flood elevation exists, the base flood elevation shall be the 100-year flood depth calculated according to the formulas presented in Depth and Frequency of Floods in Illinois published by the U.S. Geological Survey, 1976.
(D) The base flood elevation for the SFHAs of those parts of unincorporated Madison County that are within the extraterritorial jurisdiction of the city or that may be annexed into the city shall be as delineated on the 100-year flood profiles in the Flood Insurance Study of Madison County prepared by the Federal Emergency Management Agency and dated October 15, 1981.
(Prior Code, § 151.04) (Ord. 89-9, passed 12-18-1989)