§ 45-3121. Coastal high hazard area (CHHA).

The following special restrictions apply to land within the coastal high hazard area:

(1)

Existing structures located on land below the elevation of the one-hundred-year flood in the CHHA shall not be expanded.

(2)

All new construction and substantial improvements in Zones V and VE (V if base flood elevation is available) shall be elevated on pilings or columns so that:

a.

The bottom of the lowest horizontal structural member of the lowest floor (excluding the pilings or columns) is elevated to two (2) feet above the base flood level if the lowest horizontal structural member is parallel to the direction of wave approach or elevated at least two (2) feet above the base flood level if the lowest horizontal structural member is perpendicular to the direction of wave approach; and,

b.

The pile or column foundation and structure attached thereto is anchored to resist flotation, collapse, and lateral movement due to the effects of wind and water loads acting simultaneously on all building components. Wind and water loading values shall each have a one (1) percent chance of being equaled or exceeded in any given year (one (1) percent annual chance).

(3)

A registered professional engineer or architect shall develop or review the structural design, specifications and plans for the construction, and shall certify that the design and methods of construction to be used are in accordance with accepted standards of practice.

(4)

The floodplain administrator shall obtain the elevation (in relation to mean sea level) of the bottom of the lowest horizontal structural member of the lowest floor (excluding pilings and columns) of all new and substantially improved structures in Zones V and VE. The floodplain administrator shall maintain a record of all such information.

(5)

No land below the level of the one-hundred-year flood in a CHHA may be developed unless the structure or substantial improvements:

a.

Is located landward of the reach of the mean high tide.

b.

Is constructed in accordance with the building code adopted in chapter 13 of the City Code.

(6)

All new construction and substantial improvements shall have the space below the lowest floor either free of obstruction or constructed with nonsupporting breakaway walls, open wood-lattice work, or insect screening intended to collapse under wind and water loads without causing collapse, displacement, or other structural damage to the elevated portion of the building or supporting foundation system. For the purpose of this section, a breakaway wall shall have a design safe loading resistance of not less than ten (10) and no more than twenty (20) pounds per square foot. Use of breakaway walls which exceed a design safe loading resistance of twenty (20) pounds per square foot (either by design or when so required by local codes) may be permitted only if a registered professional engineer or architect certifies that the designs proposed meet the following conditions:

a.

Breakaway wall collapse shall result from water load less than that which would occur during the base flood; and

b.

The elevated portion of the building and supporting foundation system shall not be subject to collapse, displacement, or other structural damage due to the effects of wind and water loads acting simultaneously on all building components (structural and nonstructural). Maximum wind and water loading values to be used in this determination shall each have a one (1) percent chance of being equaled or exceeded in any given year.

(7)

The enclosed space below the lowest floor shall be used solely for parking of vehicles, building access, or storage. Such space shall not be partitioned into multiple rooms, temperature-controlled, or used for human habitation.

(8)

The use of fill for structural support of buildings is prohibited. When fill is proposed in a coastal high hazard area, appropriate engineering analyses shall be conducted to evaluate the impacts of the fill prior to issuance of a development permit.

(9)

No manufactured home shall be placed within the CHHA except in existing manufactured home subdivisions.

(10)

No manmade alteration of sand dunes or mangrove stands within the CHHA will be permitted which will increase potential flood damage.

(Ord. No. 5028-97, § 1; Ord. No. 5644-01; Ord. No. 7123-14, § 1)

(Ord. No. 5028-97, § 1; Ord. No. 5644-01; Ord. No. 7123-14, § 1)