A. Permitted Uses:
1. General farming, pasture, grazing, 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. 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 including pedestrian bridges.
4. Residential lawns, gardens, parking areas, and play areas.
5. Public utilities, sanitary sewer, public water, storm sewer, and street and bridge improvements.
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 increase flood elevations and shall not involve structures, fill, obstructions, excavations or storage of materials or equipment.
C. Permitted Accessory Uses: None.
D. Conditional Uses:
1. Structures accessory to the uses listed in subsection A of this section, and the uses listed in subsections D2 through D8 of this section.
2. Extraction and storage of sand, gravel, and other materials.
3. Marinas, boat rentals, docks, piers, wharves, and water control structures.
4. Railroads, utility transmission lines, and pipelines.
5. Storage yards for equipment, machinery, or materials.
6. Placement of fill and construction of fences that obstruct flood flows.
7. Recreational vehicles either on individual lots of record or in existing or new subdivisions or commercial or condominium type campgrounds, subject to the exemptions and provisions of subsection 11-101-21C of this chapter.
8. 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 10-year frequency flood event.
E. Standards For Floodway Conditional Uses:
1. All Uses: Except in areas designated for stormwater management and deeded in drainage and utility easements or as outlots to the city, no structure (temporary or permanent), fill (including fill for roads and levees), deposit, obstruction, storage of materials or equipment, or other uses may be allowed as a conditional use which, acting alone or in combination with existing or anticipated future uses, adversely affect the capacity of the floodway, or increase flood heights. Consideration of the effects of a proposed use shall be based upon the reasonable assumption that there will be an equal degree of encroachment extending for a significant reach on both sides of the stream. All conditional use applications shall be accompanied by a floodway impact statement drafted by a registered professional engineer. The city engineer shall be responsible for submitting the proposal and application to the department of natural resources and any other governmental unit having jurisdiction over the area for review and comment.
2. Fill:
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.
b. Dredge spoil sites and sand and gravel operations shall not be allowed in the floodway unless a long term site development plan is submitted which includes an erosion/sedimentation prevention element to the plan.
c. As an alternative, and consistent with subsection E2b of this section, dredge spoil disposal and sand and gravel operations may allow temporary, on site storage of fill or other materials which would have caused an increase to the stage of the 100-year or regional flood but only after the city council 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. Accessory Structures:
a. Accessory structures shall not be designed for human habitation.
b. Accessory structures, if permitted, shall be constructed and placed on the building site so as to offer the minimum obstruction to the flow of floodwaters.
(1) Whenever possible, structures shall be constructed with the longitudinal axis parallel to the direction of flood flow.
(2) So far as practicable, structures shall be placed approximately on the same flood flow lines as those of adjoining structures.
c. Accessory structures shall be elevated on fill or structurally dry floodproofed in accordance with the FP-1 or FP-2 floodproofing classifications in the state building code. As an alternative, an accessory structure may be floodproofed to the FP-3 or FP-4 floodproofing classification in the state building code provided the accessory structure constitutes a minimal investment, does not exceed five hundred (500) square feet in size at its largest projection, and for a detached garage, the detached garage must be used solely for parking of vehicles and limited storage. All floodproofed accessory structures must meet the following additional standards:
(1) The structure must be adequately anchored to prevent flotation, collapse or lateral movement of the structure and shall be designed to equalize hydrostatic flood forces on exterior walls; and
(2) Any mechanical and utility equipment in a structure must be elevated to or above the regulatory flood protection elevation or properly floodproofed.
(3) To allow for the equalization of hydrostatic pressure, there must be a minimum of two (2) automatic openings in the outside walls of the structure having a total net area of not less than one square inch for every one square foot of enclosed area subject to flooding. There must be openings on at least two (2) sides of the structure and the bottom of all openings must be no higher than one foot (1') above the lowest adjacent grade to the structure. Using human intervention to open a garage door prior to flooding will not satisfy this requirement for automatic openings.
4. Storage Of Materials And Equipment:
a. The storage or processing of materials that are in time of flooding buoyant, flammable, explosive, or could be injurious to human, animal, or plant life, is prohibited.
b. Storage of other material or equipment may be allowed if not subject to major damage by floods and firmly anchored to prevent flotation or readily movable from the area within the time available after a flood warning in accordance with a plan approved by the city council.
5. Garbage And Solid Waste Disposal: No conditional use permits for garbage and waste disposal sites shall be issued for floodway areas. There shall be no further encroachment upon the floodway at existing sites.
6. Structural Works:
a. 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 applicable provisions of Minnesota statutes chapter 103G. Communitywide structural works for flood control intended to remove areas from the regulatory floodplain shall not be allowed in the floodway.
b. A levee, dike or floodwall constructed in the floodway shall not cause an increase to the 100-year or regional flood and the technical analysis must assume equal conveyance or storage loss on both sides of a stream.
7. Floodway Alterations And Filling:
a. Any floodway alteration or filling shall not cause a net decrease in flood storage capacity below the regulatory flood protection elevation unless it is shown that the proposed alteration or filling, together with an equal degree of flood storage reduction on all other land in the affected reach of the water body or watercourse, will not cause high water or aggravate flooding on other land and will not unduly restrict flood flows.
b. Any alteration or filling that alters floodplain boundaries, including bridge crossings and/or regional ponds, and increases the regional flood level due to an encroachment or obstruction in the floodway may be allowed provided that:
(1) The applicant submits easements or other documentation in a form acceptable to the city demonstrating and recording the consent of the owner of any land affected by the increase in the regional flood level;
(2) The upstream impacts, riparian impacts and habitat impacts of the proposed action are analyzed and no detrimental impacts result, or adverse impacts are mitigated;
(3) The action is consistent with this chapter and state and federal regulations and a conditional and final letter of map revision is approved from the federal emergency management agency.
8. Drainage And Utility Easements: Drainage and utility easements shall be dedicated over areas in the floodway below the regulatory flood protection elevation of any water body, watercourse, or wetland or deeded to the city in an outlot in conjunction with subdivision of the land. (Ord. 883, 9-19-2011)