These standards apply to riverine regulatory floodplains without a delineated floodway.
(A) The applicant shall obtain approval from IDNR-OWR for development of more than five acres or subdivisions of more than 50 lots located, entirely or partly, within the regulatory floodplain (without a delineated regulatory floodway).
(B) The development shall not singularly or cumulatively result in an obstruction of flood flows or potential flood damages outside the site due to an increase in flood heights, velocities or loss of floodplain area storage.
(C) If the riverine floodplain without a delineated floodway is in a Zone A with no BFEs shown, then a professional engineer shall submit a study that:
(1) Determines a BFE and demonstrates that the proposed development will maintain the existing conditions conveyance, will not increase flood velocities, will not increase flood profiles and will compensate for any lost floodplain storage in accordance with this subchapter; or
(2) Shows that the proposed development will meet the requirements for regulatory floodplains within this subchapter.
(Ord. 2019-03, passed 4-15-2019)