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Coral Gables |
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Code of Ordinances |
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SubPart B. LAND DEVELOPMENT REGULATIONS |
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Chapter 113. FLOOD DAMAGE PREVENTION |
§ 113-8. Standards for subdivision and new development proposals.
(a)
Buildings and structures. Pursuant to section 113-5(c) of this chapter, buildings, structures, and facilities that are exempt from the Florida Building Code, including substantial improvement or repair of substantial damage of such buildings, structures and facilities, shall be designed and constructed in accordance with the flood load and flood resistant construction requirements of ASCE 24. Structures exempt from the Florida Building Code that are not walled and roofed buildings shall comply with the requirements of section 113-8(j) of this chapter.
If extending, in whole or in part, seaward of the coastal construction control line and also located, in whole or in part, in a flood hazard area:
(1)
Buildings and structures shall be designed and constructed to comply with the more restrictive applicable requirements of the Florida Building Code, Building Section 3109 and Section 1612 or Florida Building Code, Residential Section R322.
(2)
Minor structures and non-habitable major structures as defined in F.S. § 161.54 shall be designed and constructed to comply with the intent and applicable provisions of this chapter and ASCE 24.
(b)
Minimum requirements. Subdivision and new development proposals, including proposals for manufactured home parks and subdivisions, shall be reviewed to determine that:
(1)
All subdivision and new development proposals shall be consistent with the need to minimize flood damage and will be reasonably safe from flooding.
(2)
All subdivision and new development proposals shall have public utilities and facilities such as, sewer, gas, electrical, communications and water systems located and constructed to minimize or eliminate flood damage.
(3)
All subdivision and new development proposals shall have adequate drainage provided to reduce exposure to flood hazards; in zones AH and AO, adequate drainage paths shall be provided to guide floodwaters around and away from proposed structures.
(c)
Subdivision plats. Where any portion of proposed subdivisions including manufactured home parks and subdivisions, lies within a flood hazard area, the following shall be required:
(1)
Delineation of flood hazard areas, floodway boundaries and flood zones, and design flood elevations, as appropriate, shall be shown on preliminary plats;
(2)
Base flood elevation and flood hazard area mapping shall be provided in accordance with this chapter for subdivision proposals and other proposed development which is greater than the lesser of 50 lots or five acres;
(3)
The base flood boundary, floodway and/or V-zone boundary if applicable, and the applicable base flood elevation for the building site on each lot, shall be clearly marked on all recorded subdivision plats, be they for residential, commercial, or industrial use; and
(4)
Compliance with the site improvement and utilities requirements of section 113-8(d) of this chapter.
(d)
Limitations on sites in regulatory floodways. No development, including but not limited to site improvements, and land disturbing activity involving fill or regrading, shall be authorized in the regulatory floodway unless the floodway encroachment analysis required in this chapter demonstrates that the proposed development or land disturbing activity will not result in any increase in the base flood elevation.
(e)
Limitations on placement of fill. Subject to the limitations of this chapter, fill shall be designed to be stable under conditions of flooding including rapid rise and rapid drawdown of floodwaters, prolonged inundation, and protection against flood-related erosion and scour. In addition to these requirements, if intended to support buildings and structures (zone A only), fill shall comply with the requirements of the Florida Building Code.
(f)
Limitations on sites in coastal high hazard areas (zone V). In coastal high hazard areas, alteration of sand dunes and mangrove stands shall be permitted only if such alteration is approved by the Florida Department of Environmental Protection and only if the engineering analysis required by this chapter demonstrates that the proposed alteration will not increase the potential for flood damage. Construction or restoration of dunes under or around elevated buildings and structures shall comply with section 113-8(j)(7)(c) of this chapter.
(g)
Manufactured homes. All manufactured homes installed in flood hazard areas shall be installed by an installer that is licensed pursuant to F.S. § 320.8249, and shall comply with the requirements of Chapter 15C-1, FAC, and the requirements of this chapter. If located seaward of the coastal construction control line, all manufactured homes shall comply with the more restrictive of the applicable requirements.
(1)
Foundations. All new manufactured homes and replacement manufactured homes installed in flood hazard areas shall be installed on permanent, reinforced foundations that:
a.
In flood hazard areas (zone A) other than coastal high hazard areas, are designed in accordance with the foundation requirements of the Florida Building Code. Residential Section R322.2 and this chapter. Foundations for manufactured homes subject to section 113-8(g)(5) of this chapter are permitted to be reinforced piers or other foundation elements of at least equivalent strength.
b.
In coastal high hazard areas (zone V), are designed in accordance with the foundation reguirements of the Florida Building Code, Residential Section R322.3 and this chapter.
(2)
Anchoring. All new manufactured homes and replacement manufactured homes shall be installed using methods and practices which minimize flood damage and shall be securely anchored to an adequately anchored foundation system to resist flotation, collapse or lateral movement methods of anchoring include, but are not limited to, use of over-the-top or frame ties to ground anchors. This anchoring requirement is in addition to applicable state and local anchoring requirements for wind resistance.
(3)
Elevation. Manufactured homes that are placed, replaced, or substantially improved shall comply with section 113-8(g)(4) or 113-8(g)(5) of this chapter, as applicable.
(4)
General elevation requirement. Unless subject to the requirements of section 113-8(g)(5) of this chapter, all manufactured homes that are placed, replaced, or substantially improved on sites located: (a) outside of a manufactured home park or subdivision; (b) in a new manufactured home park or subdivision; (c) in an expansion to an existing manufactured home park or subdivision; or (d) in an existing manufactured home park or subdivision upon which a manufactured home has incurred "substantial damage" as the result of a flood, shall be elevated such that the bottom of the frame is at or above the elevation required, as applicable to the flood hazard area, in the Florida Building Code, Residential Section R322.2 (zone A) or Section R322.3 (zone V).
(5)
Elevation requirement for certain existing manufactured home parks and subdivisions. Manufactured homes that are not subject to section 113-8(g)(4) of this chapter, including manufactured homes that are placed, replaced, or substantially improved on sites located in an existing manufactured home park or subdivision, unless on a site where substantial damage as result of flooding has occurred, shall be elevated such that either the:
a.
Bottom of the frame of the manufactured home is at or above the elevation required, as applicable to the flood hazard area, in the Florida Building Code, Residential Section R322.2 (zone A) or Section R322.3 (zone V); or
b.
Bottom of the frame is supported by reinforced piers or other foundation elements of at least equivalent strength that are not less than 36 inches in height above grade.
(6)
Enclosures. Enclosed areas below elevated manufactured homes shall comply with the requirements of the Florida Building Code, Residential Section R322.2 or R322.3 for such enclosed areas, as applicable to the flood hazard area.
(7)
Utility equipment. Utility equipment that serves manufactured homes, including electric, heating, ventilation, plumbing, and air conditioning equipment and other service facilities, shall comply with the requirements of the Florida Building Code, Residential Section R322, as applicable to the flood hazard area.
(h)
Recreational vehicles and park trailers.
(1)
Temporary placement. Recreational vehicles and park trailers placed temporarily in flood hazard areas shall:
a.
Be on the site for fewer than 180 consecutive days; or
b.
Be fully licensed and ready for highway use, which means the recreational vehicle or park model is on wheels or jacking system, is attached to the site only by quick-disconnect type utilities and security devices, and has no permanent attachments such as additions, rooms, stairs, decks and porches.
(2)
Permanent placement. Recreational vehicles and park trailers that do not meet the limitations in section 113-8(h)(1) of this chapter for temporary placement shall meet the requirements of section 113-8(g) of this chapter for manufactured homes.
(i)
Tanks.
(1)
Underground tanks. Underground tanks in flood hazard areas shall be anchored to prevent flotation, collapse or lateral movement resulting from hydrodynamic and hydrostatic loads during conditions of the design flood, including the effects of buoyancy assuming the tank is empty.
(2)
Aboveground tanks, not elevated. Above-ground tanks that do not meet the elevation requirements of section [113-8(i)(3)] of this chapter shall:
a.
Be permitted in flood hazard areas (zone A) other than coastal high hazard areas, provided the tanks are anchored or otherwise designed and constructed to prevent flotation, collapse or lateral movement resulting from hydrodynamic and hydrostatic loads during conditions of the design flood, including the effects of buoyancy assuming the tank is empty and the effects of flood-borne debris.
b.
Not be permitted in coastal high hazard areas (zone V).
(3)
Aboveground tanks, elevated. Aboveground tanks in flood hazard areas shall be elevated to or above the design flood elevation and attached to a supporting structure that is designed to prevent flotation, collapse or lateral movement during conditions of the design flood. Tank-supporting structures shall meet the foundation requirements of the applicable flood hazard area.
(4)
Tank inlets and vents. Tank inlets, fill openings, outlets and vents shall be:
a.
At or above the design flood elevation or fitted with covers designed to prevent the inflow of floodwater or outflow of the contents of the tanks during conditions of the design flood; and
b.
Anchored to prevent lateral movement resulting from hydrodynamic and hydrostatic loads, including the effects of buoyancy, during conditions of the design flood.
(j)
Other development. All development, including manmade changes to improved or unimproved real estate for which specific provisions are not specified in this chapter or the Florida Building Code, shall:
• Be located and constructed to minimize flood damage;
• Meet the limitations of section 113-8(d) of this chapter if located in a regulated floodway;
• Be anchored to prevent flotation, collapse or lateral movement resulting from hydrostatic loads, including the effects of buoyancy, during conditions of the design flood;
• Be constructed of flood damage-resistant materials; and
• Have mechanical, plumbing, and electrical systems above the design flood elevation or meet the requirements of ASCE 24, except that minimum electric service required to address life safety and electric code requirements is permitted below the design flood elevation provided it conforms to the provisions of the electrical part of building code for wet locations.
(1)
Fences in regulated floodways. Fences in regulated floodways that have the potential to block the passage of floodwaters, such as stockade fences and wire mesh fences, shall meet the limitations of section 113-8(d) of this chapter.
(2)
Retaining walls, sidewalks and driveways in regulated floodways. Retaining walls and sidewalks and driveways that involve the placement of fill in regulated floodways shall meet the limitations of section 113-8(d) of this chapter.
(3)
Roads and watercourse crossings in regulated floodways. Roads and watercourse crossings, including roads, bridges, culverts, low-water crossings and similar means for vehicles or pedestrians to travel from one side of a watercourse to the other side, that encroach into regulated floodways shall meet the limitations of section 113-8(d) of this chapter. Alteration of a watercourse that is part of a road or watercourse crossing shall meet the requirements of section 113-6(c) of this chapter.
(4)
Concrete slabs used as parking pads, enclosure floors, landings, decks, walkways, patios and similar nonstructural uses in coastal high hazard areas (zone V). In coastal high hazard areas, concrete slabs used as parking pads, enclosure floors, landings, decks, walkways, patios and similar nonstructural uses are permitted beneath or adjacent to buildings and structures provided the concrete slabs are designed and constructed to be:
a.
Structurally independent of the foundation system of the building or structure;
b.
Frangible and not reinforced, so as to minimize debris during flooding that is capable of causing significant damage to any structure; and
c.
Have a maximum slab thickness of not more than four inches.
(5)
Decks and patios in coastal high hazard areas (zone V). In addition to the requirements of the Florida Building Code, in coastal high hazard areas decks and patios shall be located, designed, and constructed in compliance with the following:
a.
A deck that is structurally attached to a building or structure shall have the bottom of the lowest horizontal structural member at or above the design flood elevation and any supporting members that extend below the design flood elevation shall comply with the foundation requirements that apply to the building or structure, which shall be designed to accommodate any increased loads resulting from the attached deck.
b.
A deck or patio that is located below the design flood elevation shall be structurally independent from buildings or structures and their foundation systems, and shall be designed and constructed either to remain intact and in place during design flood conditions or to break apart into small pieces to minimize debris during flooding that is capable of causing structural damage to the building or structure or to adjacent buildings and structures.
c.
A deck or patio that has a vertical thickness of more than 12 inches or that is constructed with more than the minimum amount of fill necessary for site drainage shall not be approved unless an analysis prepared by a qualified registered design professional demonstrates no harmful diversion of floodwaters or wave runup and wave reflection that would increase damage to the building or structure or to adjacent buildings and structures.
d.
A deck or patio that has a vertical thickness of 12 inches or less and that is at natural grade or on nonstructural fill material that is similar to and compatible with local soils and is the minimum amount necessary for site drainage may be approved without requiring analysis of the impact on diversion of floodwaters or wave runup and wave reflection.
(6)
Other development in coastal high hazard areas (zone V). In coastal high hazard areas, development activities other than buildings and structures shall be permitted only if also authorized by the appropriate federal, state or local authority; if located outside the footprint of, and not structurally attached to, buildings and structures; and if analyses prepared by qualified registered design professionals demonstrate no harmful diversion of floodwaters or wave runup and wave reflection that would increase damage to adjacent buildings and structures. Such other development activities include but are not limited to:
a.
Bulkheads, seawalls, retaining walls, revetments, and similar erosion control structures;
b.
Solid fences and privacy walls, and fences prone to trapping debris, unless designed and constructed to fail under flood conditions less than the design flood or otherwise function to avoid obstruction of floodwaters; and
c.
On-site sewage treatment and disposal systems defined in 64E-6.002, FAC, as filled systems or mound systems.
(7)
Nonstructural fill in coastal high hazard areas (zone V). In coastal high hazard areas:
a.
Minor grading and the placement of minor quantities of nonstructural fill shall be permitted for landscaping and for drainage purposes under and around buildings.
b.
Nonstructural fill with finished slopes that are steeper than one unit vertical to five units horizontal shall be permitted only if an analysis prepared by a qualified registered design professional demonstrates no harmful diversion of floodwaters or wave runup and wave reflection that would increase damage to adjacent buildings and structures.
c.
Where authorized by the Florida Department of Environmental Protection or applicable local approval, sand dune construction and restoration of sand dunes under or around elevated buildings are permitted without additional engineering analysis or certification of the diversion of floodwater or wave runup and wave reflection if the scale and location of the dune work is consistent with local beach-dune morphology and the vertical clearance is maintained between the top of the sand dune and the lowest horizontal structural member of the building.
(Code 1991, § 7.7-28; Code 2006, § 113-8; Ord. No. 3026, § 8, 5-11-1993; Ord. No. 2018-06, § 2(Att. A), 1-23-2018)