(A) Permitted uses. Permitted uses are those uses of land or structures allowed in the underlying zoning district(s) that comply with the standards in division (B) of this section. If no pre-existing, underlying zoning districts exist, then any residential or nonresidential structure or use of a structure or land is a permitted use provided it does not constitute a public nuisance.
(B) Standards for flood fringe permitted uses. In addition to the applicable standards outlined in § 154.11(B) of ths chapter:
(1) All structures, including accessory structures, must be elevated on fill so that the lowest floor, as defined, is at or above the regulatory flood protection elevation (RFPE). The finished fill elevation for structures must be no lower than one foot below the regulatory flood protection elevation (RFPE). Fill for residential structures must extend at the same elevation at least 15 feet beyond the outside limits of the structure. Elevations must be certified by a registered professional engineer, land surveyor or other qualified person designated by the community.
(2) Accessory structures. As an alternative to the fill requirements of this division any enclosed structures accessory to the uses identified in this section must meet the following provisions:
(a) Accessory structures shall constitute a minimal investment not to exceed 576 square feet in size, and only be used for parking and storage;
(b) Accessory structures must allow for the equalization of hydrostatic pressure by accommodating for the inundation of floodwaters. There shall be a minimum of two openings on at least two sides of the structure and the bottom of all openings shall be no higher than one foot above grade. The openings shall have a minimum net area of not less than one square inch for every square foot of enclosed area subject to flooding, and shall allow automatic entry and exit of floodwaters without human intervention;
(3) The cumulative placement of fill or similar material on a parcel must not exceed 1,000 cubic yards, unless the fill is specifically intended to elevate a structure in accordance with this division (B);
(4) All fill must be properly compacted and the slopes must be properly protected by the use of riprap, vegetative cover or other acceptable method;
(5) All new principal structures must have vehicular access at or above an elevation not more than two feet below the regulatory flood protection elevation, or must have a flood warning /emergency evacuation plan acceptable to the city;
(6) Accessory uses such as yards, railroad tracks, and parking lots may be at an elevation lower than the regulatory flood protection elevation. However, any facilities used by employees or the general public must be designed with a flood warning system that provides adequate time for evacuation if the area is inundated to a depth and velocity such that the depth (in feet) multiplied by the velocity (in feet per second) would exceed a product of four upon occurrence of the base flood; and
(7) Manufactured homes and recreational vehicles must also meet the standards of § 154.17 of this chapter.
(C) Conditional uses. The following uses may be allowed as conditional uses following the standards and procedures set forth in § 154.18(D) of this chapter and further subject to the standards set forth in division (D) of this section, if otherwise allowed in the underlying zoning district(s).
(1) The placement of floodproofed nonresidential basements below the regulatory flood protection elevation;
(2) The cumulative placement of more than 1,000 cubic yards of fill when the fill is not being used to elevate a structure in accordance with division (B) of this section; and
(3) The use of methods other than fill to elevate structures above the regulatory flood protection elevation. This includes the use of: stilts, pilings, filled stem walls, or above-grade, internally flooded enclosed areas such as crawl spaces or tuck under garages, meeting the standards in division (D) of this section.
(1) The standards for permitted uses in the flood fringe, listed in division (B), apply to all conditional uses.
(2) Residential basements, as defined in § 154.07, are not allowed below the RFPE.
(3) All areas of nonresidential structures, including basements, to be placed below the regulatory flood protection elevation must be structurally dry floodproofed, which requires making the structure watertight with the walls substantially impermeable to the passage of water and with structural components capable of resisting hydrostatic and hydrodynamic loads and the effects of buoyancy. A floodproofing certification consistent with § 154.18(B) of this chapter shall be required.
(4) The placement of more than 1,000 cubic yards of fill or other similar material on a parcel (other than for the purpose of elevating a structure to the regulatory flood protection elevation) must comply with an approved erosion/sedimentation control plan.
(a) The plan must clearly specify methods to be used to stabilize the fill on site for a flood event at a minimum of the base flood event;
(b) The plan must be prepared and certified by a registered professional engineer or other qualified individual acceptable to the city; and
(c) The plan may incorporate alternative procedures for removal of the material from the floodplain if adequate flood warning time exists.
(5) Alternative elevation methods other than the use of fill may be utilized to elevate a structure’s lowest floor above the regulatory flood protection elevation. The base or floor of an enclosed area shall be considered above-grade and not a structure’s basement or lowest floor if:
(a) The enclosed area is above grade on at least one side of the structure;
(b) It is designed to internally flood; and
(c) It is used solely for parking of vehicles, building access or storage. These alternative elevation methods are subject to the following additional standards.
(1) Above-grade, fully-enclosed areas such as crawl spaces or tuck under garages must be designed to internally flood and include a minimum of two openings on at least two sides of the structure. The bottom of all openings shall be no higher than one foot above grade, and have a minimum net area of not less than one square inch for every square foot of enclosed area subject to flooding unless a registered professional engineer or architect certifies that a smaller net area would suffice.
(2) Floodproofing certifications consistent with § 154.18(B) of this chapter shall be required. The structure shall be subject to a deed-restricted non-conversion agreement with the issuance of any permit.
(Ord. passed 10-22-2020) Penalty, see § 154.99