§ 70-159. Provisions for flood hazard reduction.
(a)
General standards. In all areas of special flood hazard, all development sites including new construction and substantial improvements shall be reasonably safe from flooding, and meet the following provisions:
(1)
New construction and substantial improvements shall be designed or modified and adequately anchored to prevent flotation, collapse, and lateral movement of the structure resulting from hydrodynamic and hydrostatic loads, including the effects of buoyancy.
(2)
Manufactured homes shall be anchored to prevent flotation, collapse, and lateral movement. Methods of anchoring may include, but are not limited to, use of over-the-top or frame ties to ground anchors. This standard shall be in addition to and consistent with applicable state requirements for resisting wind forces.
(3)
New construction and substantial improvements shall be constructed with materials and utility equipment resistant to flood damage.
(4)
New construction and substantial improvements shall be constructed by methods and practices that minimize flood damage.
(5)
Electrical, heating, ventilation, plumbing, air conditioning equipment and other service facilities, including duct work, shall be designed and/or located so as to prevent water from entering or accumulating within the components during conditions of flooding.
(6)
New and replacement water supply systems shall be designed to minimize or eliminate infiltration of floodwaters into the systems.
(7)
New and replacement sanitary sewage systems shall be designed to minimize or eliminate infiltration of floodwaters into the systems and discharges from the systems into floodwaters.
(8)
On-site waste disposal systems shall be located and constructed to avoid impairment to them or contamination from them during flooding.
(9)
Any alteration, repair, reconstruction or improvements to a building that is in compliance with the provisions of this article shall meet the requirements of new construction as contained in this article.
(10)
Any alteration, repair, reconstruction or improvements to a building that is not in compliance with the provisions of this article, shall be undertaken only if said nonconformity is not furthered, extended, or replaced.
(11)
All applicable additional federal, state, and local permits shall be obtained and submitted to the floodplain administrator along with the application for development permit. Copies of such permits shall be maintained on file with the development permit. State permits may include, but not be limited to, the following:
a.
St. Johns River Water Management District: in accordance with F.S. § 373.036(2)(a), Flood Protection and Floodplain Management;
b.
Department of community affairs: in accordance with F.S. § 380.05, Areas of Critical State Concern, and F.S. ch. 553, part IV, Florida Building Code;
c.
Department of health: in accordance with F.S. § 381.0065, on-site sewage treatment and disposal systems.
(12)
Standards for subdivision proposals and other new proposed development (including manufactured homes):
a.
Such proposals shall be consistent with the need to minimize flood damage;
b.
Such shall have public utilities and facilities such as sewer, gas, electrical, and water systems located and constructed to minimize or eliminate flood damage; and
c.
Such proposals shall have adequate drainage provided to reduce exposure to flood hazards.
(13)
When proposed new construction and substantial improvements are partially located in an area of special flood hazard, the entire structure shall meet the standards for new construction.
(14)
When proposed new construction and substantial improvements are located in multiple flood hazard risk zones or in a flood hazard risk zone with multiple base flood elevations, the entire structure shall meet the standards for the most hazardous flood hazard risk zone and the highest base flood elevation.
(b)
Specific standards. In all A zones where base flood elevation data have been provided (Zones AE, A1-30, A with base flood elevation, and AH), as set forth in subsection 70-157(b), the following provisions, in addition to those set forth in subsection (a) of this section, shall apply:
(1)
Residential construction. All new construction and substantial improvement of any residential building (including a manufactured home) shall have the lowest floor, including basement, elevated to no lower than one foot above the base flood elevation. Should solid foundation perimeter walls be used to elevate a structure, there must be a minimum of two openings on different sides of each enclosed area sufficient to facilitate automatic equalization of flood hydrostatic forces in accordance with standards of subsection (b)(3) of this section.
(2)
Non-residential construction. All new construction and substantial improvement of any commercial, industrial, or non-residential building (including manufactured homes) shall have the lowest floor, including basement, elevated no lower than one foot above the base flood elevation. All buildings located in A zones may be floodproofed in lieu of being elevated provided all of the building's components and attendant utilities and sanitary facilities located below the base flood elevation or one foot above the base flood elevation 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 registered professional engineer or architect shall certify the standards of this subsection are satisfied using the FEMA floodproofing certificate. Such certification with the corresponding engineering data, and operational and maintenance plans shall be provided to the floodplain administrator.
(3)
Enclosures below the lowest floor. New construction and substantial improvements that include fully enclosed areas formed by foundation and other exterior walls below the lowest floor 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 either be certified by a professional engineer or architect or meet or exceed the following minimum criteria:
1.
Provide a minimum of two openings on different sides of each enclosed area having a total net area not less than one square inch for every square foot of enclosed area subject to flooding;
2.
The bottom of all openings shall be no higher than one foot above 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 provide the required net area of the openings and permit the automatic flow of floodwaters in both directions;
b.
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); and
c.
The interior portion of such enclosed area shall not be finished or partitioned into separate rooms.
(4)
Standards for manufactured homes and recreational vehicles.
a.
For all manufactured homes that are placed, or substantially improved within Zones A1-30, AH, and AE, on sites:
1.
Outside of an existing manufactured home park or subdivision;
2.
In a new manufactured home park or subdivision;
3.
In an expansion to an existing manufactured home park or subdivision; or
4.
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 foot above the base flood elevation and be securely anchored to an adequately anchored foundation system to resist flotation, collapse, and lateral movement. Mobile homes shall not be placed, replaced or improved within any zone.
b.
All manufactured homes to be placed or substantially improved in an existing manufactured home park or subdivision that are not subject to the provisions of subsection (b)(4)a of this section, must be elevated so that either:
1.
The lowest floor of the manufactured home is elevated to no lower than one foot above the base flood elevation; or
2.
The manufactured home is supported by reinforced piers or other foundation elements of at least an equivalent strength that are no less than 36 inches in height above grade and securely anchored to an adequately anchored foundation system to resist flotation, collapse, and lateral movement.
c.
Placement of new manufactured homes is prohibited within the regulatory floodway, even in an existing manufactured home park or subdivision. A replacement manufactured home may be placed on a lot in an existing manufactured home park or subdivision provided the anchoring standards of subsection (a)(2) of this section, the elevation standards of subsections (b)(1) and (2) of this section, and the encroachment standard of subsection (b)(6)a of this section, are met.
d.
All recreational vehicles must either:
1.
Be on the site for fewer than 180 consecutive 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).
(5)
Drainage paths. Adequate drainage paths around structures shall be provided on slopes to guide water away from structures within Zone AH.
(6)
Standards for waterways with established base flood elevations and floodways. Located within areas of special flood hazard established in section 70-157(b), are areas designated as floodways. Since the 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 (b)(1) through (5) of this section, shall apply:
a.
Prohibit encroachments, including fill, new construction, substantial improvements and other developments within the regulatory floodway unless certification (with supporting technical data) by a registered professional engineer is provided through hydrologic and hydraulic analyses performed in accordance with standard engineering practice demonstrating that encroachments would not result in any increase in flood levels during occurrence of the base flood discharge.
b.
Development activities including new construction and substantial improvements within the regulatory floodway that increase the base flood elevation may be allowed, provided that the developer or applicant first applies, with the community's endorsement, for a conditional FIRM revision, and receives the approval of FEMA.
c.
When fill is proposed, in accordance with the permit issued by the state department of health, within the regulatory floodway, the development permit shall be issued only upon demonstration by appropriate engineering analyses that the proposed fill will not increase the water surface elevation of the base flood in accordance with subsection (b)(6)a of this section.
(Code 1999, § 78-194; Ord. No. 2009-04, art. I, 12-8-2009)