Sec. 46-85Standards for areas of shallow flooding (AO zones)

Areas of special flood hazard established in section 46-52, may include designated "AO" shallow flooding areas. These areas have base flood depths of one to three feet above ground, with no clearly defined channel. The following provisions apply:

(1) All new construction and substantial improvements of residential and nonresidential structures shall have the lowest floor, including basement, elevated to the flood-depth number specified on the flood insurance rate map (FIRM), above the highest adjacent grade. If no flood-depth number is specified, the lowest floor, including basement, shall be elevated at least three feet above the highest adjacent grade. Openings sufficient to facilitate the unimpeded movements of floodwaters shall be provided in accordance with standards of subsection 46-81(4), "Elevated buildings."

The building department shall certify the lowest floor elevation level and the record shall become a permanent part of the permit file.

(2) New construction or the substantial improvement of a nonresidential structure may be floodproofed in lieu of elevation. The structure, together with attendant utility and sanitary facilities, must be designed to be watertight to the specified FIRM flood level plus one foot, above highest adjacent grade, with walls substantially impermeable to the passage of water, and structural components having the capability of resisting hydrostatic and hydrodynamic loads and the effect of buoyancy. A registered professional engineer or architect shall certify that the design and methods of construction are in accordance with accepted standards of practice for meeting the provisions above, and shall provide such certification to the official as set forth above and as required in subsections 46-72(1)c. and 46-72(2).

(3) Drainage paths shall be provided to guide floodwater around and away from any proposed structure.

History: (Ord. No. 09-04, art. 4, § E, 8-6-2009)