An application for a permit shall meet the following requirements:
(A) All projects shall be designed and constructed to ensure that they do not adversely affect the flood hazard on other properties and are reasonably safe from flooding;
(B) All projects shall assure that the carrying capacity of the floodway is not reduced. All projects in the floodway shall meet the following:
(1) Demonstrate that the project does not increase the base flood elevation by conducting an encroachment analysis certified by an engineer;
(2) A minimal or qualitative encroachment analysis may be accepted when the project or development does not require a structure, alteration of the floodway, involve fill, grading, excavation, or storage of materials or equipment, but is also certified by an engineer to not exceed the allowable encroachment to the base flood elevation; and
(3) The allowable encroachment to the base flood elevation is zero feet, and no significant increase to the velocity or flow of the stream or water course, unless approval of an alteration of the regulated flood hazard area pursuant to § 11.06.040.030 and an approved FEMA conditional letter of map revision occurs before permit issuance (ARM §§ 36.15.505, 36.15.604 and 36.15.605(b); 44 C.F.R. §§ 60.3(a)(3), (a)(4) and65.12(a)).
(C) An application for a floodplain permit must also demonstrate the following factors are considered and incorporated into the design of the use or artificial obstruction in the floodway:
(1) The danger to life and property due to backwater or diverted flow caused by the obstruction or use (ARM § 36.15.216(2)(a));
(2) The danger that the obstruction or use may be swept downstream to the injury of others (ARM § 36.15.216(2)(b));
(3) The availability of alternative locations (ARM § 36.15.216(2)(c));
(4) Construct or alter the obstruction or use in such manner as to lessen the flooding danger (ARM § 36.15.216(2)(d));
(5) The permanence of the obstruction or use and is reasonably safe from flooding (ARM § 36.15.216(2)(e));
(6) The anticipated development in the foreseeable future of the area which may be affected by the obstruction or use (ARM § 36.15.216(2)(f));
(7) Relevant and related permits for the project have been obtained (C.F.R. § 60.3(a)(2));
(8) Such other factors as are in harmony with the purposes of these regulations, the Montana Floodplain and Floodway Management Act, and the accompanying Administrative Rules of Montana (ARM § 36.15.216(2)(g)); and
(9) The safety of access to property in times of flooding for ordinary and emergency services (44 C.F.R. § 60.22(c)(7); higher standard).
(Prior Code, § 11.06.090.020) (Ord. 6, passed 3-16-1981; Ord. 2021-15, passed 12-20-2021)
Statutory reference:
Similar provisions, see MCA § 76-5-406(1) through (7)