3.02.05 - Basis for Establishing the Areas of Special Flood Hazard
3.02.06 - General Standards for Flood Hazard Reduction
3.02.07 - Specific Standards for Construction Within Coastal High Hazard Areas
3.02.08 - Regulations Within the Floodways
3.02.09 - Regulations for Mobile Homes and Recreational Vehicles
3.02.10 - Standards for Subdivision Plats
A.
The flood hazard areas of the County are subject to periodic inundation, which could result in loss of life, property damage, health, and safety hazards, disruption of commerce and governmental services, extraordinary public expenditures for flood protection and relief, and impairment of the tax base, all of which could adversely affect the public health, safety, and general welfare.
B.
These flood losses are caused by the cumulative effect of obstructions in flood plains causing increases in flood heights and velocities, and by the occupancy in flood hazard areas by structures vulnerable to floods or hazardous to the lands which are inadequately elevated, floodproofed, or otherwise inadequately protected from flood damages.
It is the purpose of this section to promote the public health, safety, and general welfare, and to minimize public and private losses due to flood conditions in specific areas by provisions designed:
A.
To protect human life and health;
B.
To minimize expenditure of public money for costly and environmentally unsound flood control projects;
C.
To minimize the need for rescue and relief efforts associated with flooding and generally undertaken at the expense of the general public;
D.
To minimize prolonged business interruptions;
E.
To minimize damage to public facilities and utilities, such as water and gas mains, electric, telephone and sewer lines, streets, and bridges located in areas of special flood hazard;
F.
To help maintain a stable tax base by providing for the sound use and development of flood prone areas in such a manner as to minimize future flood blight areas;
G.
To ensure, to the greatest degree possible, that potential home buyers are notified that property is in an area of special flood hazard; and
H.
To ensure that those who occupy the areas of special flood hazard assume responsibilities for their actions.
This section shall apply to all areas of special flood hazard in the unincorporated area of the County, and identified by the Federal Insurance Administration in its flood insurance rate map (FIRM), dated November 17, 2005, and any revisions thereto.
(Ord. No. 08-08, § 3.D)
Mobile homes to be placed in an existing mobile home park shall be exempt from the requirements of this section, provided such mobile home park is not expanded or undergoes substantial improvement as defined herein.
3.02.05 - Basis for Establishing the Areas of Special Flood Hazard
The areas of special flood hazard, are identified by the Federal Insurance Administration, in a scientific and engineering report entitled "The flood insurance study" for the County's unincorporated area, dated June 3, 1986, with accompanying FIRM, dated November 17, 2005, The flood insurance study and accompanying FIRM shall be on file and be open for public inspection in the office of the Clerk to the BCC located in Building "F", Collier County Courthouse, 3301 Tamiami Trail, East, Naples, Florida 34112.
(Ord. No. 08-08, § 3.E)
3.02.06 - General Standards for Flood Hazard Reduction
In all areas of special flood hazards, the following provisions are required:
A.
All new construction and substantial improvements shall be anchored to prevent flotation, collapse, or lateral movement of the structure.
B.
New construction and substantial improvements in the A Zones may be built on unconstrained, but compacted, fill, if in compliance with the Collier County Building Code Ordinance. No significant water is permitted to flow from the subject premises onto abutting properties or into adjoining waters which are not County-approved drainage system(s).
C.
Residential Construction - new construction or substantial improvement of any residential structure shall have the lowest floor elevated to or above the base flood elevation.
D.
Non-residential Construction - new construction and substantial improvements of non-residential structures shall have the lowest floor (including basement) elevated to or above the base flood level or, together with the attendant utility and sanitary facilities, be designed so that, below the base flood level, the structure is essentially waterproofed with walls substantially impermeable to the passage of water and with structural components having the capability of resisting hydrostatic and hydrodynamic loads and effects of buoyancy. Floodproofing is prohibited in the velocity (V) zones. The property owners shall provide a certification by a registered professional engineer or registered professional architect that the design standards of this section are satisfied.
E.
All new construction and substantial improvements shall be constructed with electrical, heating, ventilation, plumbing, air conditioning equipment, and other service facilities that are designed and/or located so as to prevent water from entering or accumulating within the components during conditions of flooding.
F.
All new construction or substantial improvements shall be constructed by methods and practices that will minimize flood damage.
G.
Openings - all new construction and substantial improvements with fully enclosed areas below the lowest floor that are subject to flooding shall be designed to automatically equalize hydrostatic flood forces on exterior walls by allowing for the entry and exit of floodwaters. Designs for meeting this requirement must either be certified by a registered professional engineer or architect, or meet or exceed the following minimum criteria: a minimum of two (2) openings having a total net area of not less than one (1) square inch for every square foot of enclosed area subject to flooding shall be provided. The bottom of all openings shall be no higher than one (1) foot above the level of the floor they are to service. Openings may be equipped with screens, louvers, valves, or other coverings or devices, provided that they permit the automatic entry and exit of floodwaters.
H.
All new and replacement water supply systems shall be designed to minimize or eliminate infiltration of flood waters into the system.
I.
New and replacement sanitary sewage systems shall be designed to minimize or eliminate inflow of flood waters into the systems and discharges from the systems into flood waters.
J.
On-site waste disposal systems (including septic tanks) shall be designed and/or located to minimize or eliminate impairment to, or contamination from, them during flooding.
K.
Emergency generators for standpipe systems, in accordance with the requirements of the Collier County Building Code or other applicable County Ordinances, must be located above the base flood elevation level, and all fuel tanks for said generators must be waterproofed and vented above the base flood elevation level.
L.
Electrical transformer and/or switching vaults, pad-mounted transformers, pad-mounted switches, and related facilities shall be permitted as independent units below the minimum flood elevation level. Such structures may be located within or outside a building, and are not required to be waterproofed or constructed with breakaway walls, provided registered professional engineer or registered professional architect certifies that they will not adversely affect the structural integrity of the building in which they are located or any part thereof.
M.
All meter enclosures for self-contained electric kilowatt-hour meters serving buildings shall be located above the base flood elevation. If complying with this regulation results in a vertical distance from finished grade to the center of the meter or meters of more than six (6) feet, the meter enclosure shall be located on the outside of an exterior wall with an unobstructed and ready access from an open exterior stairway. When it is necessary to use a stairway for access to a meter, the vertical distance from the tread of the stairway to the center of the meter shall be four (4) to six (6) feet. The meter shall be placed in a position that will not obstruct stairway traffic. On multi-unit buildings, meters and meter Enclosures will be allowed within the building, provided they are above the base flood elevation and located in meter rooms.
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.
3.02.08 - Regulations Within the Floodways
A.
When floodways are designated within areas of special flood hazard, additional criteria shall be met. Since the floodway is an extremely hazardous area due to the velocity of flood waters, which carry debris, potential projectiles, and erosion potential, the following provision shall apply:
1.
Encroachments, including fill, new construction, substantial improvements and other developments, are prohibited, unless the property owner provides a certification by a professional registered engineer demonstrating that such encroachments shall not result in a significant increase in flood levels during occurrence of the base flood discharge.
3.02.09 - Regulations for Mobile Homes and Recreational Vehicles
A.
No mobile home shall be placed in the coastal high hazard area, as depicted on the county-wide Future Land Use Map, or in a floodway, except in an existing mobile home park or existing mobile home subdivision, or land already zoned to allow mobile home development.
B.
All mobile homes placed, or substantially improved, on individual lots or parcels, in expansions to existing mobile home parks or subdivisions, must meet all the requirements for new construction, including elevation and anchoring.
C.
All mobile homes to be placed, or substantially improved, in an existing mobile home park or subdivision must be elevated on a permanent foundation such that the lowest floor of the mobile home is at or above the base flood elevation, and securely anchored to an adequately anchored foundation system in accordance with the provisions of this LDC. This paragraph applies to:
1.
Mobile homes to be placed, or substantially improved, in an existing mobile home park or subdivision.
2.
Mobile homes to be placed, or substantially improved, in an existing mobile home park or subdivision, except where the repair, reconstruction, or improvement of the streets, utilities, and pads equals or exceeds 50 percent of the value of the streets, utilities, and pads before the repair, reconstruction, or improvement has commenced. Existing mobile homes that are substantially improved will require reinforced piers or other foundation elements that are no less than 36 inches in height above grade, or have their lowest floor at or above the base flood elevation, if this allows for use of a lower foundation.
3.
Mobile homes in existing mobile home parks or subdivisions shall be elevated 36 inches above finished grade on reinforced piers when the repair, reconstruction, or improvement of the streets, utilities, and pads equals or exceeds 50 percent of the value of the streets, utilities, and pads before the repair, reconstruction, or improvement has commenced.
D.
All mobile home parks or subdivisions must develop, and have approved by the County Manager or designee, a plan for evacuating the residents of existing mobile home parks or subdivisions.
E.
All recreational vehicles placed on sites within Zones Al-30, AH, and AE on the community's FIRM shall either:
1.
Be on the site for fewer than 180 consecutive days;
2.
Be fully licensed and ready for highway use; or
3.
Meet the permit requirements of this section, and the elevation and anchoring requirements for "mobile homes" in accordance with this section.
F.
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.
(Ord. No. 08-63, § 3.F)
3.02.10 - Standards for Subdivision Plats
A.
All subdivision plats shall be consistent with the need to minimize flood damage.
B.
All subdivision plats shall have public utilities and facilities, such as sewer, gas, electrical, and water systems, located and constructed to minimize flood damage.
C.
All subdivision plats shall have adequate drainage provided to reduce exposure to flood hazards.
D.
Base flood elevation data shall be shown on the Master Subdivision Plan.
E.
All final plats presented for approval shall clearly indicate the finished elevation of the roads, the average finished elevation of the lots or homesite, and the minimum base flood elevation as required in this section. All grades must be shown in both NAVD and NGVD. The information may be shown referenced to one datum with a note on the cover sheet listing a site-specific equation for determining the grades in the other datum.
(Ord. No. 06-63, § 3.L)