§ 3.02.07. Specific Standards for Construction Within Coastal High Hazard Areas

A.

Coastal high hazard areas within the areas of special flood hazard have special flood hazards associated with high velocity waters from tidal surge and hurricane wave wash. Therefore, the following provisions shall apply:

1.

All new construction and substantial improvements in the coastal high hazard area shall be elevated on pilings and columns so that the bottom of the lowest horizontal structural member of the lowest floor (excluding the pilings or columns) is elevated to or above the base flood level; and 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 (100-year mean recurrence interval). 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 for meeting the provisions this paragraph.

2.

All new construction and substantial improvements within the coastal high hazard area shall have the space below the lowest floor either free of obstruction or constructed with non-supporting 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 purposes 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 or State Codes) may be permitted only if a registered professional engineer or architect certifies that the design proposed meets the following conditions:

a.

Breakaway wall collapse shall result from a water load less than that which could 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 on building components (structural and non-structural). Maximum wind and water loading values to be used in this determination shall each have one (1) percent chance of being equaled or exceeded in any given year (100-year mean recurrence interval). Such enclosed space shall be usable solely for parking of vehicles, building access , or storage.

3.

All swimming pools within the coastal high hazard area shall be anchored to a pile or column foundation to resist flotation, collapse, and lateral movement due to the effects of wind and water loads acting simultaneously on the pool. Exception: above-ground pools, for the private use of one- or two-family dwellings that are constructed with a vinyl liner as the main component.

4.

It is prohibited to use fill for structural support of buildings within the coastal high hazard area . It is prohibited to alter sand dunes and mangrove stands, within the coastal high hazard area , if the County Manager or designee determines that such alteration would increase potential flood damage.