CHAPTER 1101
FLOOD PLAIN MANAGEMENT REGULATIONS
Section
1101.01   Statutory authorization, findings of fact and purpose
1101.02   General provisions
1101.03   Establishment of zoning districts
1101.04   Floodway District (FW)
1101.05   Flood Fringe District (FF)
1101.06   General Floodplain District (GF)
1101.07   Land development standards
1101.08   Public utilities, railroads, roads and bridges
1101.09   Manufactured homes and placement of recreational vehicles
1101.10   Administration
1101.11   Nonconformities
1101.12   Penalties and enforcement
1101.13   Amendments
1101.01 STATUTORY AUTHORIZATION, FINDINGS OF FACT AND PURPOSE.
Subd. 1.   Statutory authorization. The legislature of the State of Minnesota has, in M.S. Ch. 103F and Ch. 462 delegated the responsibility to local government units to adopt regulations designed to minimize flood losses. Therefore, the City Council does ordain as follows.
Subd. 2.   Purpose.
      a.   This chapter regulates development in the flood hazard areas of the city. These flood hazard areas are subject to periodic inundation, which may result in loss of life and property, health and safety hazards, disruption of commerce and governmental services, extraordinary public expenditures for flood protection and relief, and impairment of the tax base. It is the purpose of this chapter to promote the public health, safety, and general welfare by minimizing these losses and disruptions.
      b.   National Flood Insurance Program compliance. This chapter is adopted to comply with the rules and regulations of the National Flood Insurance Program codified as 44 Code of Federal Regulations Parts 59 -78, as amended, so as to maintain the community's eligibility in the National Flood Insurance Program.
      c.   This chapter is also intended to preserve the natural characteristics and functions of watercourses and floodplains in order to moderate flood and stormwater impacts, improve water quality, reduce soil erosion, protect aquatic and riparian habitat, provide recreational opportunities, provide aesthetic benefits and enhance community and economic development.
(Ord. 534, passed 10-24-2016)
1101.02 GENERAL PROVISIONS.
Subd. 1.   How to use this chapter. This chapter adopts the floodplain maps applicable to the city and includes three floodplain districts: Floodway, Flood Fringe, and General Floodplain.
      a.   Where Floodway and Flood Fringe districts are delineated on the floodplain maps, the standards in §§ 1101.04 or 1101.05 will apply, depending on the location of a property.
      b.   Locations where Floodway and Flood Fringe districts are not delineated on the floodplain maps are considered to fall within the General Floodplain district. Within the General Floodplain district, the Floodway District standards in § 1101.04 apply unless the floodway boundary is determined, according to the process outlined in § 1101.06. Once the floodway boundary is determined, the Flood Fringe District standards in § 1101.05 may apply outside the floodway.
Subd. 2.   Lands to which chapter applies.
      a.   This chapter applies to all lands within the jurisdiction of the city shown on the floodplain maps and/or the attachments to the maps as being located within the boundaries of the Floodway, Flood Fringe, or General Floodplain districts.
      b.   The Floodway, Flood Fringe and General Floodplain districts are overlay districts that are superimposed on all existing zoning districts on the Zoning Districts map referenced in Chapter 1201 of this code. The standards imposed in the overlay districts are in addition to any other requirements in Chapter 1201 of this Code. In case of a conflict, the more restrictive standards will apply.
Subd. 3.   Incorporation of maps by reference. The following maps together with all attached material are hereby adopted by reference and declared to be a part of this chapter. The attached material includes the Flood Insurance Study for Hennepin County, Minnesota, and Incorporated Areas, dated November 4, 2016 and the Flood Insurance Rate Map panels enumerated below, dated November 4, 2016, all prepared by the Federal Emergency Management Agency. These materials are on file in the City Offices.
      Effective Flood Insurance Rate Map panels: 27053C0292 F, 27053C0295 F, 27053C0308 F, 27053C0309 F, 27053C0311 F, 27053C0312 F, 27053C0313 F, 27053C0314 F, 27053C0316 F, 27053C0317 F, 27053C0318 F, 27053C0319 F.
Subd. 4.   Regulatory flood protection elevation. The regulatory flood protection elevation (RFPE) is an elevation no lower than one foot above the elevation of the regional flood plus any increases in flood elevation caused by encroachments on the floodplain that result from designation of a floodway.
Subd. 5.   Interpretation. The boundaries of the floodplain districts are determined by scaling distances on the Flood Insurance Rate Map.
      a.   Where a conflict exists between the floodplain limits illustrated on the flood plain map and floodplain elevations discover in actual field conditions, the flood elevations shall be the governing factor. The Zoning Administrator must interpret the boundary location based on the ground elevations that existed on the site on the date of the first National Flood Insurance Program map showing the area within the regulatory floodplain, and other available technical data.
      b.   Persons contesting the location of the district boundaries will be given a reasonable opportunity to present their case to the City Council, serving as the Board of Adjustments and Appeals and to submit technical evidence.
Subd. 6.   Abrogation and greater restrictions. It is not intended by this chapter to repeal, abrogate, or impair any existing easements, covenants, or other private agreements. However, where this chapter imposes greater restrictions, the provisions of this chapter prevail. All other ordinances inconsistent with this chapter are hereby repealed to the extent of the inconsistency only.
Subd. 7.   Warning and disclaimer of liability. This chapter does not imply that areas outside the floodplain districts or land uses permitted within such districts will be free from flooding or flood damages. This chapter does not create liability on the part of the city or its officers or employees for any flood damages that result from reliance on this chapter or any administrative decision lawfully made hereunder.
Subd. 8.   Severability. If any section, clause, provision, or portion of this chapter is adjudged unconstitutional or invalid by a court of law, the remainder of this chapter shall not be affected and shall remain in full force.
Subd. 9.   Definitions. Unless specifically defined below, words or phrases used in this chapter must be interpreted according to common usage and so as to give this chapter its most reasonable application.
         ACCESSORY USE OR STRUCTURE. A use or structure on the same lot with, and of a nature customarily incidental and subordinate to, the principal use or structure.
         BASE FLOOD ELEVATION. The elevation of the REGIONAL FLOOD. The term BASE FLOOD ELEVATION is used in the flood insurance survey.
         BASEMENT. Any area of a structure, including crawl spaces, having its floor or base subgrade (below ground level) on all four sides, regardless of the depth of excavation below ground level.
         CONDITIONAL USE. A specific type of structure or land use listed in the official control that may be allowed but only after an in-depth review procedure and with appropriate conditions or restrictions as provided in the official zoning controls or building codes and upon a finding that:
            (1)   Certain conditions as detailed in the zoning code exist.
            (2)   The structure and/or land use conform to the comprehensive land use plan if one exists and are compatible with the existing neighborhood.
         CRITICAL FACILITIES. Facilities necessary to a community's public health and safety, those that store or produce highly volatile, toxic or water-reactive materials, and those that house occupants that may be insufficiently mobile to avoid loss of life or injury. Examples of critical facilities include hospitals, correctional facilities, schools, daycare facilities, nursing homes, fire and police stations, wastewater treatment facilities, public electric utilities, water plants, fuel storage facilities, and waste handling and storage facilities.
         DEVELOPMENT. Any manmade change to improved or unimproved real estate, including buildings or other structures, mining, dredging, filling, grading, paving, excavation or drilling operations, or storage of equipment or materials.
         EQUAL DEGREE OF ENCROACHMENT. A method of determining the location of floodway boundaries so that floodplain lands on both sides of a stream are capable of conveying a proportionate share of flood flows.
         FLOOD. A temporary increase in the flow or stage of a stream or in the stage of a wetland or lake that results in the inundation of normally dry areas.
         FLOOD FREQUENCY. The frequency for which it is expected that a specific flood stage or discharge may be equaled or exceeded.
         FLOOD FRINGE. The portion of the Special Flood Hazard Area (1% annual chance flood) located outside of the floodway. FLOOD FRINGE is synonymous with the term FLOODWAY FRINGE used in the flood insurance study for Hennepin County, Minnesota.
         FLOOD PRONE AREA. Any land susceptible to being inundated by water from any source (see FLOOD).
         FLOODPLAIN. The beds proper and the areas adjoining a wetland, lake or watercourse which have been or hereafter may be covered by the regional flood.
         FLOODPROOFING. A combination of structural provisions, changes, or adjustments to properties and structures subject to flooding, primarily for the reduction or elimination of flood damages.
         FLOODWAY. The bed of a wetland or lake and the channel of a watercourse and those portions of the adjoining floodplain which are reasonably required to carry or store the regional flood discharge.
         LOWEST FLOOR. The lowest floor of the lowest enclosed area (including basement). An unfinished or flood resistant enclosure, used solely for parking of vehicles, building access, or storage in an area other than a basement area, is not considered a building's lowest floor; provided, that such enclosure is not built so as to render the structure in violation of the applicable non-elevation design requirements of 44 Code of Federal Regulations, Part 60.3.
         MANUFACTURED HOME. A structure, transportable in one or more sections, which is built on a permanent chassis and is designed for use with or without a permanent foundation when attached to the required utilities. The term MANUFACTURED HOME does not include the term RECREATIONAL VEHICLE.
         NEW CONSTRUCTION. Structures, including additions and improvements, and placement of manufactured homes, for which the start of construction commenced on or after the effective date of this chapter.
         OBSTRUCTION. Any dam, wall, wharf, embankment, levee, dike, pile, abutment, projection, excavation, channel modification, culvert, building, wire, fence, stockpile, refuse, fill, structure, or matter in, along, across, or projecting into any channel, watercourse, or regulatory floodplain which may impede, retard, or change the direction of the flow of water, either in itself or by catching or collecting debris carried by such water.
         ONE HUNDRED YEAR FLOODPLAIN. Lands inundated by the REGIONAL FLOOD (see definition).
         PRINCIPAL USE OR STRUCTURE. All uses or structures that are not accessory uses or structures.
         REACH. A hydraulic engineering term to describe a longitudinal segment of a stream or river influenced by a natural or man-made obstruction. In an urban area, the segment of a stream or river between two consecutive bridge crossings would most typically constitute a reach.
         RECREATIONAL VEHICLE. A vehicle that is built on a single chassis, is 400 square feet or less when measured at the largest horizontal projection, is designed to be self-propelled or permanently towable by a light duty truck, and is designed primarily not for use as a permanent dwelling but as temporary living quarters for recreational, camping, travel, or seasonal use. For the purposes of this chapter, the term RECREATIONAL VEHICLE is synonymous with the term TRAVEL TRAILER/TRAVEL VEHICLE.
         REGIONAL FLOOD. A flood which is representative of large floods known to have occurred generally in Minnesota and reasonably characteristic of what can be expected to occur on an average frequency in the magnitude of the 1% chance or 100-year recurrence interval. REGIONAL FLOOD is synonymous with the term BASE FLOOD used in a flood insurance study.
         REGULATORY FLOOD PROTECTION ELEVATION (RFPE). An elevation not less than one foot above the elevation of the regional flood plus any increases in flood elevation caused by encroachments on the floodplain that result from designation of a floodway.
         REPETITIVE LOSS. Flood related damages sustained by a structure on two separate occasions during a ten year period for which the cost of repairs at the time of each such flood event on the average equals or exceeds 25% of the market value of the structure before the damage occurred.
         SPECIAL FLOOD HAZARD AREA. A term used for flood insurance purposes synonymous with ONE HUNDRED YEAR FLOODPLAIN.
         START OF CONSTRUCTION. Includes substantial improvement, and means the actual start of construction, repair, reconstruction, rehabilitation, addition, placement or other improvement that occurred before the permit's expiration date. The actual start is either the first placement of permanent construction of a structure on a site, such as the pouring of slab or footings, the installation of piles, the construction of columns, or any work beyond the stage of excavation; or the placement of a manufactured home on a foundation. Permanent construction does not include land preparation, such as clearing, grading and filling; nor does it include the installation of streets and/or walkways; nor does it include excavation for a basement, footings, piers, foundations, or the erection of temporary forms; nor does it include the installation on the property of accessory buildings, such as garages or sheds not occupied as dwelling units or not part of the main structure. For a substantial improvement, the actual start of construction means the first alteration of any wall, ceiling, floor, or other structural part of a building, whether or not that alteration affects the external dimensions of the building.
         STRUCTURE. Anything constructed or erected on the ground or attached to the ground or on-site utilities, including, but not limited to, buildings, factories, sheds, detached garages, cabins, manufactured homes, recreational vehicles not meeting the exemption criteria specified in § 1101.09 Subd. 2. of this chapter and other similar items.
         SUBSTANTIAL DAMAGE. Damage of any origin sustained by a structure where the cost of restoring the structure to its before damaged condition would equal or exceed 50% of the market value of the structure before the damage occurred.
         SUBSTANTIAL IMPROVEMENT. Within any consecutive 365-day period, any reconstruction, rehabilitation (including normal maintenance and repair), repair after damage, addition, or other improvement of a structure, the cost of which equals or exceeds 50% of the market value of the structure before the START OF CONSTRUCTION of the improvement. This term includes structures that have incurred SUBSTANTIAL DAMAGE, regardless of the actual repair work performed. The term does not, however, include either:
            (1)   Any project for improvement of a structure to correct existing violations of state or local health, sanitary, or safety code specifications which have been identified by the local code enforcement official and which are the minimum necessary to assure safe living conditions.
            (2)   Any alteration of a HISTORIC STRUCTURE, provided that the alteration will not preclude the structure's continued designation as a HISTORIC STRUCTURE. For the purpose of this chapter, HISTORIC STRUCTURE is as defined in 44 Code of Federal Regulations, Part 59.1.
Subd.10.    Annexations. The Flood Insurance Rate Map panels adopted by reference into § 1101.02 Subd. 3. above may include floodplain areas that lie outside of the corporate boundaries of the city at the time of adoption of this chapter. If any of these floodplain land areas are annexed into the city after the date of adoption of this chapter, the newly annexed floodplain lands will be subject to the provisions of this chapter immediately upon the date of annexation.
Subd. 11.    Detachments. The Flood Insurance Rate Map panels adopted by reference into § 1101.02 Subd. 3. above will include floodplain areas that lie inside the corporate boundaries of municipalities at the time of adoption of this chapter. If any of these floodplain land areas are detached from a municipality and come under the jurisdiction of the city after the date of adoption of this chapter, the newly detached floodplain lands will be subject to the provisions of this chapter immediately upon the date of detachment.
(Ord. 534, passed 10-24-2016)
1101.03 ESTABLISHMENT OF ZONING DISTRICTS.
Subd. 1.   Districts.
      a.   Floodway District. The Floodway District includes those areas within Zones AE that have a floodway delineated as shown on the Flood Insurance Rate Map adopted in § 1102.02 Subd. 3., as well as portions of other lakes, wetlands, and basins within Zones AE (that do not have a floodway delineated) that are located at or below the ordinary high water level as defined in M.S. § 103G.005, Subd. 14.
      b.   Flood Fringe District. The Flood Fringe District includes areas within Zones AE that have a floodway delineated on the Flood Insurance Rate Map adopted in § 1102.02 Subd. 3., but are located outside of the floodway. For other lakes, wetlands and other basins within Zones AE that do not have a floodway delineated, the Flood Fringe District also includes those areas below the 1% annual chance (100-year) flood elevation but above the ordinary high water level as defined in M.S. § 103G.005, Subd. 14.
      c.   General Floodplain District. The General Floodplain District includes those areas within Zone A as shown on the Flood Insurance Rate Map adopted in § 1102.02, Subd. 3.
Subd. 2.   Applicability. Within the floodplain districts established in this chapter, the use, size, type and location of development must comply with the terms of this chapter and other applicable regulations. In no cases shall floodplain development adversely affect the efficiency or unduly restrict the capacity of the channels or floodways of any tributaries to the main stream, drainage ditches, or any other drainage facilities or systems. All uses not listed as permitted uses or conditional uses in §§ 1101.04, 1101.05, and 1101.06, are prohibited. In addition, critical facilities, as defined in § 1102.02 (Critical Facilities), are prohibited in all floodplain districts.
(Ord. 534, passed 10-24-2016)
1101.04 FLOODWAY DISTRICT (FW).
Subd. 1.   Permitted uses. The following uses, subject to the standards set forth in § 1101.04 Subd. 2., are permitted uses if otherwise allowed in the underlying zoning district or any applicable overlay district:
      a.   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, fishing areas, and single or multiple purpose recreational trails.
      b.   Residential lawns, gardens, parking areas, and play areas.
      c.   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.
Subd. 2.   Standards for floodway permitted uses.
      a.   The use must have a low flood damage potential.
      b.   The use must not obstruct flood flows or cause any increase in flood elevations and must not involve structures, obstructions, or storage of materials or equipment.
      c.   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.
Subd. 3.   Conditional uses. The following uses may be allowed as conditional uses following the standards and procedures set forth in § 1101.10 Subd.4. of this chapter and further subject to the standards set forth in § 1101.04 Subd. 4., if otherwise allowed in the underlying zoning district or any applicable overlay district.
      a.   Structures accessory to the uses listed in §§ 1101.04 Subd. 1. a. through c. above and the uses listed in b. through c. below.
      b.   Extraction and storage of sand, gravel, and other materials.
      c.   Marinas, boat rentals, docks, piers, wharves, and water control structures.
      d.   Storage yards for equipment, machinery, or materials.
      e.   Placement of fill or construction of fences that obstruct flood flows.
      f.   General farming, pasture, grazing, outdoor plant nurseries, horticulture, truck farming, forestry, sod farming, and wild crop harvesting.
Subd. 4.   Standards for floodway conditional uses.
      a.   All uses. A conditional use must not cause any increase in the stage of the 1% chance or regional flood or cause an increase in flood damages in the reach or reaches affected.
      b.   Fill; storage of materials and equipment.
         (1)   The storage or processing of materials that are, in time of flooding, flammable, explosive, or potentially injurious to human, animal, or plant life is prohibited.
         (2)   Fill, dredge spoil, and other similar materials deposited or stored in the floodplain must 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.
         (3)   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 if the City Council has approved a plan that assures removal of the materials from the floodway based upon the flood warning time available.
      c.   Accessory structures. Accessory structures, as identified in § 1101.04 Subd. 3.a., may be permitted, provided that:
         (1)   Structures are not intended for human habitation;
         (2)   Structures will have a low flood damage potential;
         (3)   Structures will be constructed and placed so as to offer a minimal obstruction to the flow of flood waters;
         (4)   Service utilities, such as electrical and heating equipment, within these structures must be elevated to or above the regulatory flood protection elevation or properly floodproofed; and
         (5)   Structures must be elevated on fill or structurally dry floodproofed in accordance with the FP1 or FP2 floodproofing classifications in the State Building Code. All floodproofed structures must be adequately anchored to prevent flotation, collapse or lateral movement and designed to equalize hydrostatic flood forces on exterior walls.
         (6)   As an alternative, an accessory structure may be internally/wet floodproofed to the FP3 or FP4 floodproofing classifications in the State Building Code, provided the accessory structure constitutes a minimal investment and does not exceed 576 square feet in size. Designs for meeting this requirement must either be certified by a registered professional engineer or meet or exceed the following criteria:
            (a)   To allow for the equalization of hydrostatic pressure, there must be a minimum of two automatic openings in the outside walls of the structure, with a total net area of not less than one square inch for every square foot of enclosed area subject to flooding; and
            (b)   There must be openings on at least two sides of the structure and the bottom of all openings must be no higher than one foot 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.
      d.   Structural works for flood control that will change the course, current or cross section of protected wetlands or public waters are subject to the provisions of M.S. § 103G.245.
      e.   A levee, dike or floodwall constructed in the floodway must not cause an increase to the 1% chance or regional flood. The technical analysis must assume equal conveyance or storage loss on both sides of a stream.
      f.   Floodway developments must not adversely affect the hydraulic capacity of the channel and adjoining floodplain of any tributary watercourse or drainage system.
(Ord. 534, passed 10-24-2016)
1101.05 FLOOD FRINGE DISTRICT (FF).
Subd. 1.   Permitted uses. Permitted uses are those uses of land or structures allowed in the underlying zoning district(s) that comply with the standards in Subd. 2. below. 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.
Subd. 2.   Standards for flood fringe permitted uses.
      a.   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. The finished fill elevation for structures must be no lower than one foot below the regulatory flood protection elevation and the fill must extend at the same elevation at least 15 feet beyond the outside limits of the structure.
      b.   Accessory structures. As an alternative to the fill requirements of a. above, structures accessory to the uses identified in Subd. 1. above may be permitted to be internally/wet floodproofed to the FP3 or FP4 floodproofing classifications in the State Building Code, provided that:
         (1)   The accessory structure constitutes a minimal investment, does not exceed 576 square feet in size, and is only used for parking and storage.
         (2)   All portions of floodproofed accessory structures below the regulatory flood protection elevation must be:
            (a)   Adequately anchored to prevent flotation, collapse or lateral movement and designed to equalize hydrostatic flood forces on exterior walls;
            (b)   Be constructed with materials resistant to flood damage; and
            (c)   Must have all service utilities be water-tight or elevated to above the regulatory flood protection elevation.
         (3)   Designs for meeting this requirement must either be certified by a registered professional engineer or meet or exceed the following criteria:
            (a)   To allow for the equalization of hydrostatic pressure, there must be a minimum of two automatic openings in the outside walls of the structure, with a total net area of not less than one square inch for every square foot of enclosed area subject to flooding; and
            (b)   There must be openings on at least two sides of the structure and the bottom of all openings must be no higher than one foot 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.
      c.   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 Subd. 2.a. of this section, or if allowed as a conditional use under Subd. 3.c. below.
      d.   The storage of any materials or equipment must be elevated on fill to the regulatory flood protection elevation.
      e.   All service utilities, including ductwork, must be elevated or water-tight to prevent infiltration of floodwaters.
      f.   The storage or processing of materials that are, in time of flooding, flammable, explosive, or potentially injurious to human, animal, or plant life is prohibited.
      g.   All fill must be properly compacted and the slopes must be properly protected by the use of riprap, vegetative cover or other acceptable method.
      h.   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 Council.
      i.   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 regional (1% chance) flood.
      j.   Manufactured homes and recreational vehicles must meet the standards of § 1101.09 of this chapter.
Subd. 3.   Conditional uses. The following uses and activities may be allowed as conditional uses, if allowed in the underlying zoning district(s) or any applicable overlay district, following the procedures in § 1101.10 Subd. 4. of this chapter.
      a.   Any structure that is not elevated on fill or floodproofed in accordance with Subd. 2.a. and 2.b. of this section.
      b.   Storage of any material or equipment below the regulatory flood protection elevation.
      c.   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 Subd. 2.a. of this section.
      d.   The use of methods to elevate structures above the regulatory flood protection elevation, including stilts, pilings, parallel walls, or above-grade, enclosed areas such as crawl spaces or tuck under garages, shall meet the standards in Subd. 4.f. of this section.
Subd. 4.   Standards for Flood Fringe conditional uses.
      a.   The standards listed in Subd. 2.d. through 2.j. apply to all conditional uses.
      b.   Basements, as defined by § 1101.02 Subd. 9. of this chapter, are subject to the following:
         (1)   Residential basement construction is not allowed below the regulatory flood protection elevation.
         (2)   Nonresidential basements may be allowed below the regulatory flood protection elevation provided the basement is structurally dry floodproofed in accordance with Subd. 4.c. below.
      c.   All areas of nonresidential structures, including basements, to be placed below the regulatory flood protection elevation must be floodproofed in accordance with the structurally dry floodproofing classifications in the State Building Code. Structurally dry floodproofing must meet the FP1 or FP2 floodproofing classification in the State Building Code, 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.
      d.   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.
         (1)   The plan must clearly specify methods to be used to stabilize the fill on site for a flood event at a minimum of the regional (1% chance) flood event.
         (2)   The plan must be prepared and certified by a registered professional engineer or other qualified individual acceptable to the City Council.
         (3)   The plan may incorporate alternative procedures for removal of the material from the floodplain if adequate flood warning time exists.
      e.   Storage of materials and equipment below the regulatory flood protection elevation must comply with an approved emergency plan providing for removal of such materials within the time available after a flood warning.
      f.   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: 1) the enclosed area is above-grade on at least one side of the structure; 2) it is designed to internally flood and is constructed with flood resistant materials; and 3) it is used solely for parking of vehicles, building access or storage. The above-noted alternative elevation methods are subject to the following additional standards:
         (1)   Design and certification. The structure's design and as-built condition must be certified by a registered professional engineer as being in compliance with the general design standards of the State Building Code and, specifically, that all electrical, heating, ventilation, plumbing and air conditioning equipment and other service facilities must be at or above the regulatory flood protection elevation or be designed to prevent flood water from entering or accumulating within these components during times of flooding.
         (2)   Specific standards for above-grade, enclosed areas. Above-grade, fully enclosed areas such as crawl spaces or tuck under garages must be designed to internally flood and the design plans must stipulate:
            (a)   The minimum area of openings in the walls where internal flooding is to be used as a floodproofing technique. 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 automatic openings shall 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. The automatic openings may be equipped with screens, louvers, valves, or other coverings or devices provided that they permit the automatic entry and exit of flood waters without any form of human intervention; and
            (b)   That the enclosed area will be designed of flood resistant materials in accordance with the FP3 or FP4 classifications in the State Building Code and shall be used solely for building access, parking of vehicles or storage.
(Ord. 534, passed 10-24-2016)
1101.06 GENERAL FLOODPLAIN DISTRICT (GF).
Subd. 1.   Permitted uses.
      a.   The uses listed in § 1101.04 Subd. 1. of this chapter, Floodway District permitted uses, are permitted uses.
      b.   All other uses are subject to the floodway/flood fringe evaluation criteria specified in § 1101.06 Subd. 2. below. Section 1101.04 applies if the proposed use is determined to be in the Floodway District. Section 1101.05 applies if the proposed use is determined to be in the Flood Fringe District.
Subd. 2.   Procedures for floodway and flood fringe determinations.
      a.   Upon receipt of an application for a permit or other approval within the General Floodplain District, the Zoning Administrator must obtain, review and reasonably utilize any regional flood elevation and floodway data available from a federal, state, or other source.
      b.   If regional flood elevation and floodway data are not readily available, the applicant must furnish additional information, as needed, to determine the regulatory flood protection elevation and whether the proposed use would fall within the Floodway or Flood Fringe District. Information must be consistent with accepted hydrological and hydraulic engineering standards and the standards in Subd. 2.c. below.
      c.   The determination of floodway and flood fringe must include the following components, as applicable:
         (1)   Estimate the peak discharge of the regional (1% chance) flood.
         (2)   Calculate the water surface profile of the regional flood based upon a hydraulic analysis of the stream channel and overbank areas.
         (3)   Compute the floodway necessary to convey or store the regional flood without increasing flood stages more than 0.5 foot. A lesser stage increase than 0.5 foot is required if, as a result of the stage increase, increased flood damages would result. An equal degree of encroachment on both sides of the stream within the reach must be assumed in computing floodway boundaries.
      d.   The Zoning Administrator will review the submitted information and assess the technical evaluation and the recommended Floodway and/or Flood Fringe District boundary. The assessment must include the cumulative effects of previous floodway encroachments. The Zoning Administrator may seek technical assistance from a designated engineer or other expert person or agency, including the Department of Natural Resources. Based on this assessment, the Zoning Administrator may approve or deny the application.
      e.   Once the Floodway and Flood Fringe District boundaries have been determined, the Zoning Administrator must process the permit application consistent with the applicable provisions of §§ 1101.04 and 1101.05 of this chapter.
(Ord. 534, passed 10-24-2016)
1101.07 LAND DEVELOPMENT STANDARDS.
Subd. 1.   In general. Recognizing that flood prone areas may exist outside of the designated floodplain districts, the requirements of this chapter apply to all land within the city.
Subd. 2.   Subdivisions. No land may be subdivided which is unsuitable for reasons of flooding or inadequate drainage, water supply or sewage treatment facilities. Manufactured home parks and recreational vehicle parks or campgrounds are considered subdivisions under this chapter.
      a.   All lots within the floodplain districts must be able to contain a building site outside of the Floodway District at or above the regulatory flood protection elevation.
      b.   All subdivisions must have road access both to the subdivision and to the individual building sites no lower than two feet below the regulatory flood protection elevation, unless a flood warning emergency plan for the safe evacuation of all vehicles and people during the regional (1% chance) flood has been approved by the City Council. The plan must be prepared by a registered engineer or other qualified individual, and must demonstrate that adequate time and personnel exist to carry out the evacuation.
      c.   For all subdivisions in the floodplain, the Floodway and Flood Fringe District boundaries, the regulatory flood protection elevation and the required elevation of all access roads must be clearly labeled on all required subdivision drawings and platting documents.
      d.   In the General Floodplain District, applicants must provide the information required in § 1101.06 Subd.2. of this chapter to determine the regional flood elevation, the Floodway and Flood Fringe District boundaries and the regulatory flood protection elevation for the subdivision site.
      e.   If a subdivision proposal or other proposed new development is in a flood prone area, any such proposal must be reviewed to assure that:
         (1)   All such proposals are consistent with the need to minimize flood damage within the flood prone area;
         (2)   All public utilities and facilities, such as sewer, gas, electrical, and water systems are located and constructed to minimize or eliminate flood damage; and
         (3)   Adequate drainage is provided to reduce exposure of flood hazard.
Subd. 3.   Building sites. If a proposed building site is in a flood prone area, all new construction and substantial improvements (including the placement of manufactured homes) must be:
      a.   Designed (or modified) and adequately anchored to prevent floatation, collapse, or lateral movement of the structure resulting from hydrodynamic and hydrostatic loads, including the effects of buoyancy;
      b.   Constructed with materials and utility equipment resistant to flood damage;
      c.   Constructed by methods and practices that minimize flood damage; and
      d.   Constructed with electrical, heating, ventilation, plumbing, and air conditioning equipment and other service facilities that are designed and/or located so as to prevent water from entering or accumulating within the components during conditions of flooding.
(Ord. 534, passed 10-24-2016)
1101.08 PUBLIC UTILITIES, RAILROADS, ROADS AND BRIDGES.
Subd. 1.   Public utilities. All public utilities and facilities such as gas, electrical, sewer, and water supply systems to be located in the floodplain must be floodproofed in accordance with the State Building Code or elevated to the regulatory flood protection elevation.
Subd. 2.   Public transportation facilities. Railroad tracks, roads, and bridges to be located within the floodplain must comply with §§ 1101.04 and 1101.05 of this chapter. These transportation facilities must be elevated to the regulatory flood protection elevation where failure or interruption of these facilities would result in danger to the public health or safety or where such facilities are essential to the orderly functioning of the area. Minor or auxiliary roads or railroads may be constructed at a lower elevation where failure or interruption of transportation services would not endanger the public health or safety.
Subd. 3.   On-site water supply and sewage treatment systems. Where public utilities are not provided: 1) On-site water supply systems must be designed to minimize or eliminate infiltration of flood waters into the systems and are subject to the provisions in Minnesota Rules Part 4725.4350, as amended; and 2) New or replacement on-site sewage treatment systems must be designed to minimize or eliminate infiltration of flood waters into the systems and discharges from the systems into flood waters, they must not be subject to impairment or contamination during times of flooding, and are subject to the provisions in Minnesota Rules Part 7080.2270, as amended.
(Am. Ord. 534, passed 10-24-2016)
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