§ 19-92. Specific standards.

In all A-Zones where base flood elevation data have been provided (Zones AE, A1-30, A (with base flood elevation), and Zone AH), development shall comply with the following provisions in addition to the standards set forth in section 19-91:

(1)

Residential construction. New construction or substantial improvement of any residential structure (including manufactured home) shall have the lowest floor, including basement, elevated no lower than one (1) foot above the base flood elevation. Should solid foundation perimeter walls be used to elevate a structure, there must be a minimum of two (2) openings on different sides of each enclosed area sufficient to facilitate automatic equalization of flood hydrostatic forces in accordance with the standards of subsection (3) below.

(2)

Nonresidential construction. New construction or substantial improvement of any commercial, industrial or nonresidential structure (including manufactured home) shall have the lowest floor, including basement, elevated no lower than one (1) foot above the base flood elevation. Structures located in A zones may be floodproofed, in lieu of being elevated, provided that all areas of the structure/building components, together with attendant utilities and sanitary facilities, below the base flood elevation plus one (1) foot are watertight with walls substantially impermeable to the passage of water, and use structural components having the capability of resisting hydrostatic and hydrodynamic loads and the effects of buoyancy. A Florida registered professional engineer shall certify, in accordance with section 19-69, that the standards of this subsection are satisfied using the FEMA floodproofing certificate. Such certification, along with the corresponding engineering data and the operational and maintenance plans shall be provided to the floodplain administrator.

(3)

Enclosures below the lowest floor. New construction or substantial improvements that include fully enclosed areas formed by foundation and other exterior walls below the lowest floor 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.

a.

Designs for complying with this requirement must be either certified by a Florida registered professional engineer or meet or exceed the following minimum criteria:

1.

Provide a minimum of two (2) openings on different sides of each enclosed area having a total net area of not less than one (1) square inch for every square foot of enclosed area subject to flooding;

2.

The bottom of all openings shall be no higher than one (1) foot above the foundation adjacent interior grade (which must be equal to or higher in elevation than the adjacent exterior grade); and

3.

Openings may be equipped with screens, louvers, valves or other coverings or devices, provided they meet the required net area of the openings and permit the automatic flow of floodwaters in both directions.

b.

Electrical, plumbing, and other utility connections shall be placed a minimum of one (1) foot above the base flood elevation.

c.

Fully enclosed areas below the lowest floor shall solely be used for parking of vehicles, storage, and building access. Access to the enclosed area shall be the minimum necessary to allow for parking of vehicles (garage door), limited storage of maintenance equipment used in connection with the premises (standard exterior door), or entry to the living area (stairway or elevator).

d.

The interior portion of such enclosed area shall not be partitioned or finished into separate rooms.

(4)

Manufactured homes and recreational vehicles.

a.

All manufactured homes placed or substantially improved within Zones A1-30, AH, and AE, on sites (i) outside of an existing 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, the lowest floor shall be elevated on a permanent foundation to no lower than one (1) foot above the base flood elevation and be securely anchored to an adequately anchored foundation system to resist flotation, collapse, and lateral movement in accordance with the anchoring requirements set forth in subsection 19-91(2). Substantially improved manufactured home parks or subdivisions, shall meet all the requirements for new construction, including elevation and nonelevation design requirements of this chapter.

b.

All manufactured homes placed or substantially improved in an existing manufactured home park or subdivision within Zones A-1, AH and AE, that are not subject to the provisions of paragraph (4)a., of this section, shall be elevated so that either:

1.

The lowest floor of the manufactured home is elevated to no lower than one (1) foot above the base flood elevation; or

2.

The manufactured home chassis is supported by reinforced piers or other foundation elements of at least an equivalent strength that are no less than forty-eight (48) inches in height above the grade and securely anchored to an adequately anchored foundation system to resist flotation, collapse, and lateral movement.

c.

All recreational vehicles shall either:

1.

Be on the site for fewer than one hundred eighty (180) days;

2.

Be fully licensed and ready for highway use (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); or

3.

Meet all the requirements for the new construction, including anchoring and elevation requirements in accordance with subsection (4)a. or b., above.

(5)

Critical facilities. Critical facilities shall be constructed on properly compacted fill and, to the extent possible, have the lowest floor (including basement) elevated at least one (1) foot above the elevation of the 0.2 percent annual chance floodplain. A critical facility shall have at least one (1) access road connected to land outside the 0.2 percent annual chance floodplain that is capable of supporting a 4,000-pound vehicle. The top of the road must be no lower than six (6) inches below the elevation of the 0.2 percent annual chance floodplain. Construction of new critical facilities may be permissible within the area of special flood hazard if no feasible alternative sites are available. Critical facilities constructed within the area of special flood hazard shall have the lowest floor elevated to three (3) or more feet above the level of the base flood elevation at the site. Floodproofing and sealing measures shall be taken to ensure that toxic substances will not be displaced by or released into floodwaters. Access routes elevated to or above the level of the base flood elevation shall be provided to all critical facilities to the extent possible.

(6)

Waterways with established base flood elevations, but without regulatory floodways. Located within the areas of special flood hazard established by this chapter, where streams exist for which base flood elevation data has been provided by FEMA without the delineation of the regulatory floodway (Zones AE and A1-30), the following provisions, in addition to those set forth in subsections (1) through (5) above, shall apply:

a.

Until a regulatory floodway is designated, no new construction, substantial improvements, or other development, (including fill), shall be permitted within the areas of special flood hazard, unless the applicant demonstrates that the cumulative effect of the proposed development, when combined with all other existing and anticipated development, will not increase the water surface elevation of the base flood more than one (1) foot at any point within the community; and

b.

Development which increases the water surface elevation of the base flood by more than one (1) foot may be allowed, provided that the developer or applicant first applies, with the county's endorsement evidenced by the execution of the community acknowledgment form, for a conditional FIRM revision, and receives the approval of FEMA.

(7)

Waterways with established base flood elevations and regulatory floodways. Located within the areas of special flood hazard established by this chapter are areas designated as regulatory floodways. Since the regulatory floodway is an extremely hazardous area due to the high velocity of floodwaters which carry debris, potential projectiles and have significant erosion potential, the following provisions, in addition to those set forth in subsections (1) through (5) above shall apply:

a.

Placement of any encroachments, including fill, new construction, substantial improvements, and other developments, including, but not limited to bridges and culverts, within the regulatory floodway shall be prohibited unless certification (with supporting technical data) by a Florida registered professional engineer is provided through hydraulic and hydrologic analysis performed in accordance with standard engineering practices which demonstrates that encroachments would not result in any increase in flood levels during occurrence of the base flood discharge;

b.

Placement of manufactured homes shall be prohibited within the regulatory floodway, except in existing manufactured home parks or subdivisions. A replacement manufactured home may be placed on a lot in an existing manufactured home park or subdivision provided the anchoring standards of subsection 19-91(2), the elevation standards of subsections 19-92(1) and (2), and the encroachment standards of subsection 19-92(7)(a) are met; and

c.

Development, including new construction and substantial improvements within the regulatory floodway, that increases the water surface elevation of the base flood may be allowed, provided that the applicant first applies, with the county's endorsement evidenced by the execution of the community acknowledgement form, for a conditional FIRM revision, and receives the approval of FEMA.

(Ord. No. 2009-24 , § 3, 9-22-09)