(A) The mapped boundaries of the floodplain illustrated in the referenced studies and maps in this section are a guide for determining whether property is within the regulated flood hazard area.
(B) A determination of the outer limits and boundaries of the regulated flood hazard area or the flood fringe and floodway within the regulated flood hazard area includes an evaluation of the maps, as well as the particular study data referenced in this section. Supporting study material for base flood elevations takes precedence over any map illustrations if it exists.
(C) The regulated flood hazard area boundary is delineated by the base flood elevation. The physical field regulatory boundary of the regulated flood hazard area is the actual intersection of the applicable study base flood elevation with the existing adjacent terrain of the watercourse or drainway (ARM § 36.15.501(6)).
(D) The floodway boundary where identified within the floodplain is as illustrated on the referenced maps and studies. Since the floodway boundary is a study feature, the location of the boundary may be physically located by referencing the study data to a ground feature. The Floodplain Administrator’s interpretation of the boundary and decision may be appealed as set forth in § 11.06.010.130.
(E) The Floodplain Administrator may request additional information described below to determine whether or not the proposed development is within the regulated flood hazard area.
(1) Where base flood elevations exist, the property owner may provide additional information which may include elevation information provided by an engineer or land surveyor in order to determine if the proposed development is subject to these regulations (ARM § 36.15.501(6)).
(2) Where base flood elevations do not exist, the property owner may provide additional information to be considered to determine the location of the regulatory boundary or alternatively provide a computed base flood elevation provided by an engineer.
(3) The Floodplain Administrator’s interpretation of the boundaries and decision may be appealed as set forth in § 11.06.010.130.
(F) Any owner or lessee of property who believes his or her property has been inadvertently included in the regulated flood hazard area, including the floodway or flood fringe, may submit scientific and/or technical information to the Floodplain Administrator for a determination if the property is appropriately located.
(1) Scientific or technical information submitted to FEMA by an owner to affect the insurance rating for insurance purposes may be considered by the Floodplain Administrator.
(2) (a) A determination by the Floodplain Administrator is independent of any determination by FEMA for insurance purposes.
(b) Example for informational purposes only: when property located within the regulated flood hazard area is naturally above the base flood elevation as proven by a certified elevation survey provided by an engineer or land surveyor, the property owner may submit a letter of map amendment (LOMA) to FEMA in order to affect the flood risk designation for insurance purposes. Information on the process and requirements are available through FEMA.
(Prior Code, § 11.06.040.020) (Ord. 6, passed 3-16-1981; Ord. 2021-15, passed 12-20-2021)