In all areas of special flood hazard, the following provisions
are required:
A.
New construction and substantial improvements shall be anchored to
prevent flotation, collapse or lateral movement of the structure resulting
from hydrodynamic and hydrostatic loads, including the effects of
buoyancy.
B.
Manufactured homes shall be anchored to prevent flotation, collapse
or 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.
C.
New construction and substantial improvements shall be constructed
with materials and utility equipment resistant to flood damage.
D.
New construction or substantial improvements shall be constructed
by methods and practices that minimize flood damage from the base
flood.
E.
Electrical, heating, ventilation, plumbing, air-conditioning equipment
and other service facilities shall be designed and/or located so as
to prevent water from entering or accumulating within the components
during conditions of flooding.
F.
New and replacement water supply systems shall be designed to eliminate
infiltration of floodwaters into the system.
G.
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.
H.
On-site waste disposal systems shall be located and constructed to
avoid impairment to them or contamination from them during flooding.
I.
Any alteration, repair, reconstruction or improvements to a structure
which is not in compliance with the provisions of this chapter shall
meet the requirements of "new construction" as contained in this chapter,
and shall be undertaken only if said nonconformity is not furthered,
extended or replaced.
In all areas of special flood hazard where base flood elevation data has been provided, as set forth in § 145-7 or § 145-16E(2), the following provisions are required:
A.
Residential construction. New construction and/or substantial improvement
of any residential structure (or manufactured home) shall have the
lowest floor, including basement and mechanical equipment elevated
no lower than two feet above the base flood elevation.
(1)
Should solid foundation perimeter walls be used to elevate a structure, openings sufficient to facilitate the unimpeded movements of floodwaters shall be provided in accordance with standards of Subsection C.
(2)
If a principal structure exists at the time of adoption of this chapter,
it may be replaced, subject to the elevation of the first floor, including
basement, to two feet above the base flood elevation.
(3)
In an A Zone, where no technical data has been produced by the Federal
Emergency Management Agency, the lowest floor, including basement
and mechanical equipment, shall be elevated two feet above the base
flood elevation, as determined by this community.
(4)
The Floodplain Administrator will determine the method by which base
flood elevations are determined. Methods include but are not limited
to detailed hydrologic and hydraulic analyses, use of existing data
available from other sources, use of historical data, or best supportable
and reasonable judgment in the event no data can be produced. The
applicant shall provide cross sections for determining floodway boundaries
(and thereby base flood elevations) at any proposed construction site
where FEMA maps are not available. All cross sections shall be referenced
to mean sea level and shall have vertical error tolerances of no more
than plus or minus 0.5 foot. Cross-section elevations shall be taken
at those points which represent significant breaks in slope and at
points where hydraulic characteristics of the base floodplain change.
Each cross section shall extend across the entire base floodplain
and shall be in the number and at the locations specified by the Floodplain
Administrator. If necessary to ensure that significant flood damage
will not occur, the Floodplain Administrator may require additional
cross sections or specific site elevations which extend beyond those
needed for making routine regulatory floodway boundary calculations.
(5)
Upon the completion of the structure, the elevation of the lowest
floor, including basement, shall be certified by a Kentucky registered
professional engineer or surveyor, and verified by the community building
inspection department to be properly elevated. Such certification
and verification shall be provided to the Floodplain Administrator.
B.
Nonresidential construction.
(1)
New construction or substantial improvement of any commercial, industrial or nonresidential structure shall be elevated to conform with Subsection A or, together with attendant utility and sanitary facilities:
(a)
Be floodproofed below an elevation one foot above the base flood
elevation so that the structure is watertight with walls substantially
impermeable to the passage of water;
(b)
Have structural components capable of resisting hydrostatic
and hydrodynamic loads and the effects of buoyancy;
(c)
Have the lowest floor, including basement, mechanical equipment,
and ductwork, elevated no lower than an elevation one foot above the
base flood elevation; or
(3)
All new construction and substantial improvement with fully enclosed
areas below the lowest floor (excluding basements) that are usable
solely for parking of vehicles, structure access or storage, and which
are subject to flooding, shall be constructed of flood-resistant materials
below the base flood elevation, and shall be designed to automatically
equalize hydrostatic flood forces on exterior walls by allowing for
the entry and exit of floodwater. Opening sizes (FEMA Technical Bulletin
1-93) for meeting this requirement must meet or exceed the following
minimum criteria:
(a)
Be certified by a Kentucky registered professional engineer
or architect; or
(b)
Have a minimum of two openings with a total net area of not
less than one square inch for every square foot of enclosed area subject
to flooding. The bottom of all openings shall be no higher than one
foot above grade. Openings may be equipped with screens, louvers,
valves or other coverings or devices, provided that they permit the
automatic entry and exit of floodwater.
C.
Elevated buildings. New construction or substantial improvements
of elevated structures on columns, posts or pilings that include fully
enclosed areas formed by foundation and other exterior walls below
the base flood 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.
(1)
Designs for complying with this requirement must either be certified
by a Kentucky professional engineer or architect or meet the following
minimum criteria:
(a)
Provide a minimum of two openings having a total net area of
not less than one square inch for every square foot of enclosed area
subject to flooding;
(b)
The bottom of all openings shall be no higher than one foot
above foundation exterior grade, which must be equal to in elevation
or higher than the exterior foundation grade; and
(c)
Openings may be equipped with screens, louvers, valves or other
coverings or devices, provided they permit the automatic flow of floodwaters
in both directions.
(2)
Electrical, plumbing and other utility connections are prohibited
below the base flood elevation;
(3)
Access to the enclosed area shall be the minimum necessary to allow
for parking of vehicles (garage door) or limited storage of maintenance
equipment used in connection with the premises (standard exterior
door) or entry to the living area (stairway or elevator);
(4)
The interior portion of such enclosed area shall not be partitioned
or finished into separate rooms;
(5)
The total floor area of such enclosed areas shall not exceed 300
square feet; and
(6)
For enclosures greater than seven feet in interior height, where
elevation requirements exceed six feet above the highest adjacent
grade, a copy of the legally recorded land use restriction prohibiting
the conversion of the area below the lowest floor to a use or dimension
contrary to the structures' originally approved design shall be presented
as a condition of issue of the final certificate of occupancy.
D.
Standards for manufactured homes and recreational vehicles.
(1)
All new or substantially improved manufactured homes located within
Zones A and AE on the community's Flood Insurance Rate Map (FIRM),
or in locations outside of a manufactured home park/subdivision, in
a new manufactured home park/subdivision, on individual lots or parcels,
in an expansion to an existing manufactured home park/subdivision
on which a manufactured home has incurred substantial damage as a
result of a flood must meet all the requirements for new construction,
including elevation and anchoring.
(3)
Except manufactured homes that have incurred substantial damage as
a result of a flood, all manufactured homes placed or substantially
improved in an existing manufactured home park or subdivision must
be elevated so that:
(a)
The lowest floor of the manufactured home is elevated to two
feet above the level of the base flood elevation; or
(b)
The manufactured home chassis is supported by reinforced piers
or other foundation elements of at least an equivalent strength, or
no less than 36 inches in height above grade.
(c)
The manufactured home must be securely anchored to the adequately
anchored foundation system to resist flotation, collapse and lateral
movement.
(4)
All recreational vehicles placed on sites located within Zones A
and AE of the community's Flood Insurance Rate Map (FIRM) must:
(5)
A recreational vehicle is ready for highway use if it is licensed
and insured in accordance with State of Kentucky motor vehicle regulations,
on its own wheels or jacking system, is attached to the site only
by quick-disconnect-type utilities and security devices and has no
permanently attached additions.
E.
Floodways. Located within areas of special flood hazard established in § 145-7 are areas designated as floodways. Since the floodway is an extremely hazardous area due to the velocity of floodwaters which carry debris, potential projectiles and has erosion potential, the following provisions shall apply:
(1)
Prohibit encroachments, including fill, new construction, substantial
improvements and other developments unless certification (with supporting
technical data) by a Kentucky registered professional engineer is
provided demonstrating that encroachments shall not result in any
increase in flood levels during occurrence of base flood discharge.
F.
Structures elevated on fill. A residential or nonresidential structure
may be constructed on permanent fill in accordance with the following:
(1)
The lowest floor (including basement) of the structure or addition
shall be no lower than two feet above the base flood elevation;
(2)
The fill shall be placed in layers no greater than six inches deep
before compacting and should extend at least 10 feet beyond the foundation
of the structure before sloping below the base flood elevation, said
slope being no greater than a 2:1 ratio unless a stability analysis
is provided by a Kentucky registered professional engineer;
(3)
The top of the fill shall be no lower than the base flood elevation.
However, the ten-foot minimum may be waived if a structural engineer
certifies an alternative method to protect the structure from damage
due to erosion, scour, and other hydrodynamic forces;
(4)
The fill shall not adversely affect the flow or surface drainage
from or onto neighboring properties;
(5)
All new structures built on fill must be constructed on properly
designed and compacted fill (ASTM D-698 or equivalent) that extends
beyond the structure walls before dropping below the base flood elevation
and has appropriate protection from erosion and scour. The design
of the fill or the fill standard must be approved by a Kentucky registered
professional engineer.
G.
Vegetative buffer strips shall be required for construction along
and on either side of blue-line streams, creeks, rivers, lakes and
impoundments, and all streams labeled with names or numbers on the
FIRMs. For all activities involving construction within 25 feet of
the channel, the following criteria shall be met:
(1)
A natural vegetative buffer strip shall be preserved within 25 feet
of the top of bank.
(2)
Where it is impossible to protect this vegetative buffer strip during
the construction of an appropriate use, a vegetated buffer strip shall
be established upon completion of construction.
(3)
The use of undisturbed, native riparian vegetation is preferred in
the vegetative buffer strip.
(4)
Access through the vegetative buffer strip shall be provided as specified
or required for stream maintenance purposes. Where a permanent easement
for stream maintenance exists along a channel, the portion of the
vegetative buffer strip immediately adjacent to the top of bank shall
be constructed and maintained to allow access for maintenance equipment.
Located within the areas of special flood hazard established in § 145-7, where small streams exist but where no base flood data has been provided or where base flood data has been provided without floodways, the following provisions apply:
A.
No encroachments, including fill material or structures, shall be
located within special flood hazard areas unless certification by
a Kentucky registered professional engineer is provided demonstrating
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 foot at
any point within the community. The engineering certification should
be supported by technical data that conforms to standard hydraulic
engineering principles.
A.
All subdivision proposals shall be consistent with the need to minimize
flood damage.
B.
All subdivision proposals shall have public utilities and facilities
such as sewer, gas, electrical and water systems located and constructed
to eliminate damage from the base flood and prevent inundation of
any streets, County roads or state roads or highways.
C.
All subdivision proposals shall have adequate drainage provided to
eliminate damage from the base flood.
D.
Base flood elevation data shall be provided by a Kentucky registered
professional engineer who is working in conjunction with the Kentucky
Division of Water for subdivision proposals and other proposed development
(including manufactured home parks and subdivisions) which is greater
than the lesser of 50 lots or five acres.
E.
When a portion of a proposed subdivision lies within a special flood
hazard area, only that portion clearly outside the special flood hazard
area will be considered when computing the minimum required lot size
for the development. Areas of special flood hazard shall be noted
prominently on the face of the plat to be recorded.
F.
Variances and hearings.
(1)
No division of land within areas of special flood hazard shall be
approved by the Henderson City-County Planning Commission until the
necessary variances are granted by the appeals board.
(2)
Prior to subdivision approval, the Planning Commission shall hold
a public hearing on all division of lands within areas of special
flood hazard.
G.
All subdivision plans shall show the elevation of all proposed structures
and lowest adjacent grade at each structure within a special flood
hazard area. If the site is filled above the base flood elevation,
the lowest floor and lowest adjacent grade elevations shall be certified
by a Kentucky registered professional engineer or surveyor and provided
to the Floodplain Administrator.
H.
All streets included in new subdivision proposals shall be constructed
above the base flood elevation.
Located within the areas of special flood hazard established in § 145-7 are areas designated as shallow flooding areas. These areas have special flood hazards associated with base flood depths of one foot to three feet where a clearly defined channel does not exist and where the path of flooding is unpredictable and indeterminate; therefore, the following provisions apply:
A.
All new construction and substantial improvements or residential
structures shall have the lowest floor, including basement, elevated
to or above either the base flood elevation or, in Zone AO, the flood
depth specified on the Flood Insurance Rate Map, in feet, above the
highest adjacent grade. If no depth is specified, the lowest floor,
including basement, shall be elevated no less than two feet above
the highest adjacent grade.
B.
All new construction and substantial improvements of nonresidential
structures shall:
(1)
Have the lowest floor, including basement, elevated to or above either
the base flood elevation or the flood depth specified on the Flood
Insurance Rate Map, in feet, above the highest adjacent grade. If
no flood depth is specified, the lowest floor, including basement,
shall be elevated no less than two feet above the highest adjacent
grade.
(2)
Together with attendant utility, sanitary and other public facilities,
be completely floodproofed to or above the base flood elevation so
that any space below that level is watertight 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.
For all accessory structures in special flood hazard areas designated
with the letter "A," the following provisions shall apply:
A.
Structure must be nonhabitable;
B.
Structure must be anchored to resist flotation forces.
C.
Structure shall require flood openings/vents no more than one foot
above grade, total openings are to be one square inch per one square
foot of floor area; at least two openings required on opposite walls.
D.
Structure shall be built of flood-resistant materials below the base
flood elevation.
E.
Must elevate utilities above the base flood elevation.
F.
Structure can only be used for storage or parking.
G.
Structure cannot be modified for a different use after permitting.
Critical facilities shall be located outside the limits of the
SFHA, unless no feasible alternative is available. Construction of
new critical facilities shall not be permissible within the floodway.
Critical facilities within the SFHA shall be constructed on properly
compacted fill and shall have the lowest floor (including basement)
elevated at least one foot above the elevation of the five-hundred-year
flood. Floodproofing and sealing measures shall be taken to ensure
that toxic substances will not be displaced by or released into floodwaters.
A critical facility shall have at least one access road connected
to land outside the five-hundred-year floodplain that is capable of
supporting a 12,500-pound vehicle, and the top of the access road
must be no lower than the elevation of the five-hundred-year flood.
This chapter shall become on February 20, 2013, or upon approval
of the updated Flood Insurance Rate Maps by FEMA, whichever event
occurs later.
