(A) Permitted uses. The following uses, subject to the standards set forth in § 152.147(B) are permitted uses if otherwise allowed in the underlying zoning district or any applicable overlay district:
(1) General farming, pasture, grazing, farm fences, outdoor plant nurseries, horticulture, truck farming, forestry, sod farming, and wild crop harvesting;
(2) Industrial-commercial loading areas, parking areas, and airport landing strips;
(3) Open space uses, including, but not limited to, private and public golf courses, tennis courts, driving ranges, archery ranges, picnic grounds, boat launching ramps, swimming areas, parks, wildlife and nature preserves, game farms, fish hatcheries, shooting preserves, target ranges, trap and skeet ranges, hunting and fishing areas, and single or multiple purpose recreational trails;
(4) Residential yards, lawns, gardens, parking areas, and play areas; and
(5) Railroads, streets, bridges, utility transmission lines and pipelines, provided that the Department of Natural Resources’ Area Hydrologist is notified at least ten days prior to issuance of any permit.
(B) Standards for floodway permitted uses.
(1) The use shall have a low flood damage potential.
(2) The use shall not obstruct flood flows or involve structures, fill, obstructions, excavations or storage of materials or equipment. The use must not cause any increase in flood damages, nor any increase in flood elevations in areas where a floodway has been established, as certified by a registered professional engineer.
(3) Any facility that will be 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 regional (1% chance) flood.
(C) Conditional uses. The following uses may be allowed as conditional uses following the standards and procedures set forth in § 152.153
(D) and further subject to the standards set forth in division (D) of this section, if otherwise allowed in the underlying zoning district.
(1) Structures accessory to the primary uses listed in division (A) above and the primary uses listed below;
(2) Grading, extraction, fill, and storage of soil, sand, gravel, and other materials;
(3) Marinas, boat rentals, permanent docks, piers, wharves, water control structures, and navigational facilities;
(4) Storage yards for equipment, machinery, or materials;
(5) Fences that have the potential to obstruct flood flows;
(6) Structural works for flood control such as levees, dikes and floodwalls constructed to any height where the intent is to protect individual structures and levees or dikes where the intent is to protect agricultural crops for a frequency flood event equal to or less than the ten-year frequency flood event.
(D) Standards for floodway conditional uses.
(1) A conditional use must not cause any increase in flood damages, nor any increase in flood elevations in areas where a floodway has been established, as certified by a registered professional engineer.
(2) Fill; storage of material and equipment.
(a) Fill, dredge spoil and all other similar materials deposited or stored in the floodplain shall be protected from erosion by vegetative cover, mulching, riprap or other acceptable method. Permanent sand and gravel operations and similar uses must be covered by a long-term site development plan.
(b) Temporary placement of fill, other materials, or equipment which would cause an increase to the stage of the 1% chance or regional flood may only be allowed after the County Board has approved an appropriate plan which assures the removal of the materials from the floodway based upon the flood warning time available. The conditional use permit must be title registered with the property in the Office of the County Recorder.
(3) Structural works for flood control that will change the course, current or cross- section of protected wetlands or public waters shall be subject to the provisions of M.S. § 103G.245, as it may be amended from time to time.
(4) A levee, dike or floodwall constructed in the floodway shall not cause an increase to the 1% chance or regional flood and the technical analysis must assume equal conveyance or storage loss on both sides of a stream.
(5) Accessory structures. Accessory structures, as identified in division (C)(1), may be permitted provided that:
(a) Accessory structures shall not be designed for human habitation.
(b) Accessory structures will have a low flood damage potential.
(c) Accessory structures, if permitted, shall be constructed and placed on the building site so as to offer the minimum obstruction to the flow of flood waters.
(d) Accessory structures shall be elevated on fill or structurally dry flood proofed and watertight to the regulatory flood protection elevation. Certifications consistent with § 152.153(B)(2) shall be required.
(e) As an alternative, an accessory structure may be floodproofed in a way to accommodate internal flooding. To allow for the equalization of hydrostatic pressure, 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, have a 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. A floodproofing certificate consistent with § 152.153(B)(2) shall be required.
(Ord. 47, passed 7-23-02; Am. Ord. 88-2018, passed 11-20-18; Am. Ord. 97-2021, passed 7-20-21)