In all areas of special flood hazards where base flood elevations have been provided or are otherwise determined as set forth in §§ 4-156, 4-163 subsection 8. or 4-164 subsection 1., 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 at least one foot 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 1. 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 least one foot 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 2. is satisfied.
3. Enclosures. New construction and substantial improvements, with full enclosed areas below the lowest floor that are usable solely for parking of vehicles, building access or storage in an area other than a basement 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 or meet or exceed the following minimum criteria:
a. A minimum of two openings having a total net are 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 above grade; and
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 on the county FIRM shall be installed using methods and practices that minimize flood damage and have the bottom of the I-beam elevated at least 36 inches above grade or at least at or 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. This requirement is in addition to applicable state and local anchoring requirements for resisting wind forces. The home shall be installed by a licensed installer according to state law and compliance herewith shall be certified in writing to the Floodplain Administrator by said installer prior to habitation of the manufactured home.
b. (1) Require that manufactured homes that are placed or substantially improved within Zone AE on the county FIRM on sites:
(a) Outside of a manufactured home park or subdivision;
(b) In a new manufactured home park or subdivision;
(c) In an expansion to an existing manufactured home park or subdivision; or
(d) 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 for the manufactured home is elevated at least one foot above the base flood elevation and be securely anchored to an adequately anchored foundation system to resist flotation, collapse and lateral movement.
(2) A licensed installer shall install the home in accordance with state law and compliance herewith shall be certified in writing to the Floodplain Administrator by said installer prior to habitation of the manufactured home.
c. Require that manufactured homes be placed or substantially improved on sites in an existing manufactured home park or subdivision with Zone AE on the county FIRM that are not subject to the provisions of subsection 4. be elevated so that the bottom of the I-beam of the manufactured home is at least one foot above the base flood elevation and be securely anchored to an adequately anchored foundation system to resist flotation, collapse and lateral movement. A licensed installer shall install the home in accordance with state law and compliance herewith shall be certified in writing to the Floodplain Administrator by said installer prior to habitation of the manufactured home.
5. Recreational vehicles. Require that recreational vehicles placed on sites within Zones A and AE on the county FIRM either:
a. Be on site for fewer than 180 consecutive days;
b. Be fully licensed and ready for highway use; or
c. Meet the permit requirements of § 4-164, and the elevation and anchoring requirements for manufactured homes in subsection 4. above. 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. Accessory structures to be placed on sites within Zones A and AE on the county FIRM shall comply with the following:
a. The structure shall be unfinished on the interior;
b. The structure shall be used only for parking and limited storage;
c. The structure shall not be used for human habitation. Prohibited activities or use include but are not limited to working, sleeping, living, cooking or restroom use;
d. Service facilities such as electrical and heating equipment must elevated to or above the BFE;
e. The structure shall be constructed and placed on the building site so as to offer the minimum resistance to the flow of floodwaters;
f. The structure shall be designed to have low flood damage potential and constructed with flood resistance materials;
g. The structure shall be firmly anchored to prevent flotation, collapse and lateral movement;
h. Floodway requirements must be met in the construction of the structure;
i. Opening to relieve hydrostatic pressure during a flood shall be provided below the BFE; and
j. The structure shall be located so as not to cause damage to adjacent and nearby structures.