§ 17-43. Elevation and floodproofing.

(a)

New construction and substantial improvement of any structure shall have the lowest floor, including basement, elevated to or above the regulatory flood elevation. Nonresidential structures may meet the standards in paragraph (c) below. Upon the completion of the structure the elevation of the lowest floor including basement shall be certified by a registered professional engineer or surveyor and provided to the administrator.

(b)

New construction and substantial improvement of any structure in zone AO shall have the lowest floor, including basement, higher than the highest adjacent grade at least one (1) foot higher than the depth number on the FIRM, or at least two (2) feet if no depth number is specified. Nonresidential structures may meet the standards in paragraph (c), below. Upon completion of the structure a registered professional engineer shall certify to the administrator that the elevation of the structure meets this standard.

(c)

Nonresidential construction shall either be elevated in conformance with paragraphs (a) or (b), above, or together with attendant utility and sanitary facilities:

(1)

Be floodproofed so that below the Regulatory Flood Elevation the structure is watertight with walls substantially impermeable to the passage of water;

(2)

Have structural components capable of resisting hydrostatic and hydrodynamic loads and effects of buoyancy; and

(3)

Be certified by a registered professional engineer or architect that the standards of this subsection are satisfied. Such certifications shall be provided to the Floodplain Administrator.

(d)

For all new construction and substantial improvement with fully enclosed areas below the lowest floor (excluding basements) that are usable solely for parking of vehicles, building access or storage, 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. Designs for meeting this requirement must either be certified by a registered professional engineer or architect to meet or exceed the following minimum criteria:

(1)

A minimum of two (2) openings, on different sides of each enclosed area, 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.

(2)

The bottom of all openings shall be no higher than one (1) foot above grade.

(3)

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)

If it is not feasible or desirable to meet the openings criteria stated above, a registered engineer or architect may design and certify the openings.

(e)

Manufactured homes shall meet the above standards and also the standards in Section 17-47.

(Res. No. 4742, § 3(Exh. A), 11-13-13)