In all areas of special flood hazard where base flood elevation data have been provided, as set forth in Article 3, Section 2, or Article 4, Section 3 (9), the following provisions are required:
(A) Residential Construction
. New construction or substantial improvement of any residential building (or manufactured home) shall have the lowest floor, including basement, elevated one foot above the base flood elevation. Should solid foundation perimeter walls be used to elevate a structure, openings sufficient to facilitate the unimpeded movements of flood waters shall be provided in accordance with standards of Article 5, Section 2 (3).
(B) Non-Residential Construction. New construction or substantial improvement of any commercial, industrial, or non-residential building (or manufactured home) shall have the lowest floor, including basement, elevated one foot above the base flood elevation. Buildings located in all A-Zones may be flood-proofed in lieu of being elevated, provided that all areas of the building below the required elevation are water tight with walls substantially impermeable to the passage of water, and use 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 standards of this subsection are satisfied. Such certification shall be provided to the official as set forth in Article 4, Section 3 (7).
(C) Elevated Buildings
. New construction or substantial improvements of elevated buildings that include fully enclosed areas formed by foundation and other exterior walls below the base flood elevation shall be designed to preclude finished living space and designed to allow for the entry and exit of floodwaters to automatically equalize hydrostatic flood forces on exterior walls.
(1) Designs for complying with this requirement must either be certified by a professional engineer or architect or meet the following minimum criteria:
(a) Provide 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;
(b) The bottom of all openings shall be no higher than one foot above grade; and
(c) Openings may be equipped with screens, louvers, valves or other coverings or devices provided they permit the automatic flow of floodwaters in both directions.
(2) Access to the enclosed area shall be the minimum necessary to allow for parking of vehicles (garage door) or limited storage of maintenance equipment used in connection with the premises (standard exterior door) or entry to the living area (stairway or elevator); and,
(3) The interior portion of such enclosed area shall not be partitioned or finished into separate rooms.
(D) Standards for Manufactured Homes and Recreational Vehicles.
(1) All manufactured homes placed or substantially improved (i) outside of a manufactured home park or subdivision, (ii) in a new manufactured home park or subdivision, (iii) in an expansion to an existing manufactured home park or subdivision, or, (iv) in an existing manufactured home park or subdivision on which a manufactured home has incurred "substantial damage" as the result of a flood, must meet all the requirements for new construction, including elevation and anchoring.
(2) All manufactured homes placed or substantially improved in an existing manufactured home park or subdivision must be elevated so that:
(a) The lowest floor of the manufactured home is elevated to or above the level of the base flood elevation, or
(b) The manufactured home chassis is supported by reinforced piers or other foundation elements of at least an equivalent strength, of no less than 36 inches in height above grade.
(c) The manufactured home must be securely anchored to the adequately anchored foundation system to resist flotation, collapse, and lateral movement.
(d) In an existing manufactured home park or subdivision on which a manufactured home has incurred "substantial damage" as the result of a flood, any manufactured home placed or substantially improved must meet the standards of Article 5, Section 2 (4) (b) (i) and (iii) above.
(4) All recreational vehicles placed on sites must either:
(a) Be on the site for fewer than 18O consecutive days,
(b) Be fully licensed and ready for highway use, or
(c) Meet the permit requirements for new construction, including anchoring and elevation requirements for "manufactured homes".
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.
(5) Floodways.
- Located within areas of special flood hazard established in Article 3, Section 2, are areas designated as floodways. Since the floodway is an extremely hazardous area due to the velocity of flood waters which carry debris, potential projectiles and has erosion potential, the following provisions shall apply:
(a) Prohibit encroachments, including fill, new construction, substantial improvements and other developments unless certification (with supporting technical data) by a registered professional engineer is provided demonstrating that encroachments shall not result in any increase in flood levels during occurrence of base flood discharge;
(b) If satisfied, all new construction and substantial improvements shall comply with all applicable flood hazard reduction provisions.
(Ord. 1997-06, Passed 4-14-97)