12-517: PROVISIONS FOR FLOOD HAZARD REDUCTION; SPECIFIC STANDARDS:
   A.   In all areas of special flood hazards where base flood elevation data has been provided as set forth in section 12-506, subsection 12-513A8 or 12-518C of this chapter, the following provisions are required:
      1.   Residential Construction: New construction or substantial improvement of any residential structure shall have the lowest floor, including basement, elevated at a minimum of one foot (1') above the base flood elevation. A registered professional engineer, architect, or land surveyor shall submit a certification to the floodplain administrator that the standard of this subsection, as proposed in section 12-514 of this chapter is satisfied;
      2.   Nonresidential Construction: New construction and substantial improvements of any commercial, industrial or other nonresidential structure shall have the lowest floor (including basement) elevated at a minimum of one foot (1') above the base flood level. The floodplain administrator shall maintain a record of all elevation certificates that includes the specific elevation (in relation to mean sea level) to which each structure has been elevated.
      3.   Enclosures: New construction and substantial improvements, with fully enclosed areas below the lowest floor that 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. 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.   A minimum of two (2) 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;
         b.   The bottom of all openings shall be no higher than one foot (1') above grade; or
         c.   Openings may be equipped with screens, louvers, valves, or other coverings or devices provided that they permit the automatic entry and exit of floodwaters; or
      4.   Manufactured Homes:
         a.   Require that all manufactured homes to be placed within zone A on the city of Tahlequah's FIRM shall be installed using methods and practices that minimize flood damage and have the bottom of the I beam elevated at a minimum of one foot (1') above the base flood elevation. For the purposes of this requirement, manufactured homes must be elevated and anchored to resist flotation, collapse, or lateral movement. Methods of anchoring may include, but are not limited to, use of over the top or frame ties to ground anchors. This requirement is in addition to applicable state and local anchoring requirements for resisting wind forces and a licensed installer shall install the home and place the required placard on the dwelling.
         b.   Require that manufactured homes that are placed or substantially improved within zones AE 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 a result of a flood, be elevated on a permanent foundation such that the bottom of the I beam of the manufactured home is elevated at a minimum of at least one foot (1') above the base flood elevation and be securely anchored to an adequately anchored foundation system to resist flotation, collapse, and lateral movement. Also, a licensed installer shall install the home.
         c.   Require that manufactured homes be placed or substantially improved on sites in an existing manufactured home park or subdivision within zones AE on the community's FIRM that are not subject to the provisions of this subsection A4 be elevated so that the bottom of the I beam of the manufactured home is at a minimum of one foot (1') above the base flood elevation and be securely anchored to an adequately anchored foundation system to resist flotation, collapse, and lateral movement support the manufactured home chassis and also installed by a licensed installer that complies with state law.
      5.   Recreational Vehicles: Require that recreational vehicles placed on sites within zones A and AE on the community's FIRM either:
         a.   Be on the site for fewer than one hundred eighty (180) consecutive days,
         b.   Be fully licensed and ready for highway use, or
         c.   Meet the permit requirements of section 12-514 of this chapter, and the elevation and anchoring requirements for "manufactured homes" in subsection A4 of this section. A recreational vehicle is ready for highway use if it is on its wheels or jacking system, is attached to the site only by quick disconnect type utilities and security devices, and has no permanently attached additions.
      6.   Accessory Structure:
         a.   Structure is low valued and represents a minimal investment.
         b.   Structure shall be small and not exceed six hundred (600) square feet in size.
         c.   Structure shall be unfinished on the interior.
         d.   Structure can be used only for parking and limited storage.
         e.   Structure shall not be used for human habitation (including work, sleeping, living, cooking, or restroom areas).
         f.   Service facilities such as electrical and heating equipment must be elevated to or above the BFE or floodproofed.
         g.   Structure is constructed and placed on building site so as to offer the minimum resistance to the flow of floodwaters.
         h.   Structure is designed to have low flood damage potential, i.e., constructed with flood resistant materials.
         i.   Structure is firmly anchored to prevent flotation, collapse, and lateral movement.
         j.   Floodway requirements must be met in the construction of the structure.
         k.   Openings to relieve hydrostatic pressure during a flood shall be provided below the BFE.
         l.   Structure is to be located so as not to cause damage to adjacent and nearby structures. (Ord. 1162-2009, 11-23-2009)