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Uses in a floodplain (FF) zoning district are subject to the following standards:

  1. Until a regulatory floodway has been designated, no development or substantial improvement may be permitted within special flood hazard areas unless the applicant has demonstrated that the proposed development or substantial improvement, when combined with all other existing and reasonably anticipated development or substantial improvements, will not increase the water surface elevation of the base flood more than one (1) foot at any location as shown on the Flood Insurance Study.
  2. New construction, subdivision proposals, substantial improvements, prefabricated buildings, placement of manufactured homes and other development shall require:
    1.  Designing or anchorage to prevent flotation, collapse or lateral movement of the structure resulting from hydrodynamic and hydrostatic loads including the effects of buoyancy.
    2. New or replacement water supply systems and/or sanitary sewage systems be designed to minimize or eliminate infiltration of flood waters into the systems and discharges from the systems into flood waters, and onsite waste disposal systems to located so as to avoid impairment or contamination.
    3. Construction with materials resistant to flood damage, utilizing methods and practices that minimize flood damages, and 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.
    4. A ll utility and sanitary facilities be elevated or floodproofed up to the regulatory flood protection elevation.
  3. On site waste disposal systems shall be located so as to avoid impairment or contamination in case of flooding.
  4. Residential Construction. All new residential construction and substantial improvements within the designated floodplain shall have the lowest floor, including basement, elevated to one foot or more above the base flood elevation. Nonresidential Construction. All new construction and substantial improvements of commercial, industrial, and other nonresidential structures within the designated floodplain shall either; have the lowest floor, including basement elevated one foot or more above the base flood level or shall be floodproofed to a line one foot above the base flood elevation. Attendant utility and sanitary facilitates shall also be floodproofed. A registered professional engineer or architect shall certify that such flood proofing complies with the requirements of this resolution.
  5. For all new construction and substantial improvements, fully enclosed areas below the lowest floor will be usable solely for building access. Areas other than a basement and which are subject to flooding shall be designed to automatically equalize hydrostatic flood forces on exterior walls by allowing for the entry and exit of floodwaters. The area below lowest floor subject to flooding shall be a maximum of four (4) feet in height measured from the bottom of the floor joists. Designs for meeting this requirement must either be certified by a registered professional engineer or architect or meet or exceed the following minimum criteria: A minimum of two openings having a total net area of not less than one square inch for every square foot of enclosed area subject to flooding shall be provided. The bottom of all openings shall not be higher than one foot above grade. Openings may be equipped with screens, louvers, valves, or other coverings or devices provided that they permit the automatic entry and exit of floodwaters.
  6. All electrical equipment, circuits, and installed electric appliances in new developments and substantial improvements shall be located so as to not be subject to flooding or shall be floodproofed to prevent damage resulting from flood levels exceeding the base flood elevation by one foot.
  7. The storage or processing of materials that are in time of flooding buoyant, flammable, explosive, or which could then become injurious to human, animal or plant life is prohibited; however, storage of other material or equipment may be allowed if such is not subject to major damage by floods and firmly anchored to prevent flotation or if such is readily removable from the area within the time available after flood warning.
  8. Subdivision proposal will assure that:
    1. All such proposals and other proposed new development, including manufactured home parks or subdivisions are consistent with the need to minimize flood damage;
    2. All public utilities and facilities, such as sewer, gas, electrical, and water systems are located, elevated and constructed to minimize or eliminate flood damage;
    3. Adequate drainage is provided so as to reduce exposure to flood hazards, and
    4. Proposals for development shall include base flood elevation data within such proposals for development (including proposals for manufactured home parks and subdivisions) of five (5) acres or fifty (50) lots, whichever is lesser, include within such proposals the base flood elevation.
  9. Within Zone AO all new construction and substantial improvements of residential structures shall have the lowest floor, including basement, elevated 2 feet above the highest adjacent grade by a minimum dimension in feet equal to the depth number specified on the official FIRM plus one foot. Nonresidential structures, within Zone AO, together with attendant utility and sanitary facilities must be floodproofed to such dimension.
  10. Within AH zones adequate drainage paths around structures on slopes shall be required in order to guide floodwaters around and away from proposed structures.
  11. Manufactured Homes
    1. All manufactured homes including mobile homes shall be anchored to resist flotation, collapse, or lateral movement by providing over-the-top and frame ties to ground anchors. Specific requirements shall be that:
      1. Over-the-top ties be provided at each of the four corners of the manufactured home, with two additional ties per side at intermediate locations but that manufactured homes less than fifty feet long need have but one additional tie per side; or
      2. Frame ties be provided at each corner of the home with five additional ties per side at intermediate points but that mobile homes less than 50 feet long need have but four additional ties per side; and
      3. All components of the anchoring system be capable of carrying a force of four thousand eight hundred pounds, and,
      4. Any additions to the manufactured home be similarly anchored.
    2. Require that all manufactured homes to be placed or substantially improved within special flood hazard areas on the community's FIRM on sites:
      1. Outside of a manufactured home park or subdivision,
      2. In a new manufactured home park or subdivision,
      3. In an expansion to an existing manufactured home park or subdivision, or
      4. In an existing manufactured home park or subdivision on which a manufactured home has incurred substantial damage as the result of a flood, be elevated on a permanent foundation such that the lowest floor of the manufactured home is at or above one (1) foot above the base flood elevation; and be securely anchored to an adequately anchored foundation system in accordance with the provisions of this section.
  12. Manufactured Home Parks. New manufactured home parks and expansions of existing manufactured home parks shall provide that:
    1. Adequate surface drainage and access for a hauler be provided for each lot; and,
    2. All stands or lots be of an elevation such that the lowest floor of a manufactured home placed thereupon will be one foot above the base flood elevations; and,
    3. Where such elevation is attained through the use of piers rather than compacted fill, the lots shall be large enough to permit the installation of steps, pier foundations shall be placed on stable soil no more than ten feet apart and steel reinforcement shall be provided for piers more than six feet high.
    4. Require that all manufactured homes to be placed within Zones A, AO, AH, and AE on the community's FIRM, be elevated on a permanent foundation such that the lowest floor of the manufactured home is at least one foot above the base flood elevation; and be securely anchored to an adequately anchored foundation system in accordance with the provisions of Section K 11. 


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