§ 10-57. Specific standards  

Latest version.
  • In all areas of special flood hazards where base flood elevation data has been provided as set forth in section 10-8, section 10-27(7), or section 10-58(c), the following provisions are required:

    (1) Residential construction. New construction and substantial improvement of any residential structure shall have the lowest floor, including basement, elevated to or 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 10-42(a) is satisfied.

    (2) Nonresidential construction. New construction and substantial improvements of any commercial, industrial or other nonresidential structure shall either have the lowest floor, including basement, elevated to or above the level of the base flood elevation or, together with attendant utility and sanitary facilities, be floodproofed so that below the base flood level the structure is watertight with walls substantially impermeable to the passage of water and with structural components having the capability of resisting hydrostatic and hydrodynamic loads and effects of buoyancy. A registered professional engineer or architect shall develop and/or review structural design, specifications, and plans for the construction, and shall certify that the design and methods of construction are in accordance with accepted standards of practice as outlined in this subsection. A record of such certification which includes the specific elevation (in relation to mean sea level) to which such structures are floodproofed shall be maintained by the floodplain administrator.

    (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 (1) 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 (1) foot above grade.

    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.

    (4) Manufactured homes.

    a. Require that all manufactured homes to be placed within zone A, shall be installed using methods and practices which minimize flood damage. For the purpose 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.

    b. All manufactured homes shall be in compliance with subsection (1) above.

    c. Require that all manufactured homes to be placed or substantially improved within zones A1—30, AH and AE on the community' FIRM be elevated on a permanent foundation such that the lowest floor of the manufactured home is at or above the base flood elevation; and be securely anchored to an adequately anchored foundation system in accordance with the provisions of this subsection.

    (5) Other flood-prone areas. In areas located outside an identified flood hazard area where flooding may be anticipated or has been known to occur, the top of the slab, or the lowest floor of a structure on pier and beams, must be no lower than eighteen (18) inches above the curb of the street, or eighteen (18) inches above the elevation of the highest adjacent grade around the structure, whichever is greater.

(Ord. No. 8804, Art. 5, § B, 4-11-88)