30.65.295 Coastal high hazard areas: standards.
Coastal high hazard areas are identified in the flood insurance study and depicted on the flood insurance rate maps that are adopted by SCC 30.65.040. These are areas of special flood hazard designated as zones V1-30, VE, and V. These areas have special flood hazards associated with high velocity waters from surges. In addition to other applicable provisions in this code, the following provisions shall apply in zones V1-30, VE, and V:
(1) All new construction and substantial improvements in zones V1-30 and VE (V if base flood elevation data is available) on the applicable FIRM shall meet the following standards:
(a) 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:
(i) For residential buildings, elevated one foot or more above the base flood level; or
(ii) For nonresidential buildings, elevated one foot or more above the base flood level or meet the elevation requirements of ASCE 24, whichever is higher.
(b) The pile or column foundation and the structure attached thereto must be 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 percent chance of being equaled or exceeded in any given year (100-year mean recurrence interval).
(c) A registered professional engineer or architect must 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 consistent with accepted standards of practice for meeting the provisions of subsections (1)(a) and (1)(b) of this section.
(2) The applicant shall provide the elevation (in relation to mean sea level) of the bottom of the lowest structural member of the lowest floor (excluding pilings and columns) of all new and substantially improved structures in zones V1-30, VE, and V on the applicable FIRM and determine whether such structures contain a basement.
(3) All new construction within zones V1-30, VE, and V on the applicable FIRM shall be located landward of the reach of mean high tide.
(4) All new construction and substantial improvements within zones V1-30, VE, and V on the applicable FIRM 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 walls shall be designed and constructed to have a safe loading resistance of not less than 10 and not more than 20 pounds per square foot; or
(b) Use of breakaway walls which exceed a design safe loading resistance of 20 pounds per square foot (either by design or when so required by local or state codes) may be permitted only when:
(i) A registered professional engineer or architect certifies that the proposed design meets the following conditions:
(A) Breakaway wall collapse will result from a water load less than that which would occur during the base flood; and
(B) The elevated portion of the building and supporting foundation system is not 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 non-structural). Maximum wind and water loading values to be used in this determination shall each have a one percent chance of being equaled or exceeded in any given year (100-year mean recurrence interval).
(ii) The enclosed space created by breakaway walls is useable solely for parking of vehicles, building access, or storage. Such space shall not be used for human habitation.
(5) The use of fill for structural support of buildings within zones V1-30, VE, and V on the applicable FIRM is prohibited.
(6) Man-made alteration of sand dunes within zones V1-30, VE, and V on the applicable FIRM which would increase potential flood damage is prohibited.
(7) All mobile homes to be placed or substantially improved on sites within zones V1-30, V, and VE on the applicable FIRM and that are located outside of a mobile home park or subdivision, in a new mobile home park or subdivision, in an expansion to an existing mobile home park or subdivision, or in an existing mobile home park or subdivision on which a mobile home has incurred "substantial damage" as the result of a flood shall meet the standards of subsections (1) through (6) of this section.
(8) All mobile homes to be placed or substantially improved on sites within zones V1-30, V, and VE on the applicable FIRM and that are located in an existing mobile home park or subdivision shall meet the requirements of SCC 30.65.110(1) and 30.65.120(4).
(9) Recreational vehicles placed on sites within V or VE zones on the applicable FIRM shall:
(b) Be fully licensed and ready for highway use, on its wheels or jacking system, attached to the site only by quick disconnect type utilities and security devices, and have no permanently attached additions. (Added by Ord. 20-076, Nov. 4, 2020, Eff date Nov. 27, 2020).