In all areas of special flood hazards the following standards are required:
(a)
Anchoring.
(1)
All new construction, substantial improvements, and other proposed new development
shall be adequately anchored to prevent flotation, collapse or lateral movement of
the structure resulting from hydrodynamic and hydrostatic loads, including the effects
of buoyancy.
(2)
All manufactured homes shall meet the anchoring standards of section 15A-19.
(b)
Construction Materials and Methods.
(1)
All new construction, substantial improvement and other proposed new development shall
be constructed with materials and utility equipment resistant to flood damage.
(2)
All new construction, substantial improvement and other proposed new development shall
be constructed using methods and practices that minimize flood damage.
(3)
All new construction, substantial improvement and other proposed new development shall
be constructed with electrical, heating, ventilation, plumbing and 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.
(4)
Within zones AH or AO, the floodplain administrator shall require that adequate drainage
paths around structures on slopes to guide flood waters around and away from proposed
structures.
(c)
Elevation and Floodproofing.
(1)
New construction, substantial improvement and other proposed new development shall
have the lowest floor, including basement, elevated two feet above the base flood
elevation (BFE), unless such minimum elevation is lowered by the floodplain administrator
at his discretion (but not below the BFE). Nonresidential structures may meet the
standards in subsection (c)(3) of this section. Prior to erection of wall framing,
the elevation of the lowest floor including basement shall be certified by a registered
professional engineer or surveyor, or verified by the floodplain administrator to
be properly elevated.
(2)
New construction, substantial improvement, and other proposed new development in Zone
AO shall have the lowest floor, including basement, elevated two feet above the highest
adjacent grade, at least two feet higher than the depth number specified, in feet,
on the FIRM, or at least two feet above adjacent grade if no depth number is specified
unless such minimum elevation is lowered by the floodplain administrator at his discretion
(but not below the BFE). Nonresidential structures may meet the standards in subsection
(c)(3). Prior to erection of wall framing, the elevation of the lowest floor including
basement shall be certified by a registered professional engineer or surveyor, or
verified by the floodplain administrator to be properly elevated.
(3)
Nonresidential construction shall either be elevated to conform with subsections (c)(1)
or (2), or together with attendant utility and sanitary facilities:
(A)
Be floodproofed two feet above the base flood elevation (BFE) so that the structure
is watertight with walls substantially impermeable to the passage of water; and
(B)
Have structural components capable of resisting hydrostatic and hydrodynamic loads
and effects of buoyancy; and
(C)
Be certified by a registered professional engineer or architect that the standards
of this subsection are satisfied. Such certifications shall be provided to the floodplain
administrator.
(4)
The floodplain administrator shall require, for all new construction, substantial
improvement and other proposed new development, that fully enclosed areas below the
lowest floor that are usable solely for parking of vehicles, building access or storage
in an area other than a basement and which are subject to flooding shall be designed
to automatically equalize hydrostatic flood forces on exterior walls by allowing for
the entry and exit of floodwater. 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)
Either 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 shall be provided;
the bottom of all such 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); or
(B)
Be certified to comply with a local floodproofing standard approved by the Federal
Insurance Administration, Federal Emergency Management Agency.
(5)
Manufactured homes shall also meet the standards in section 15A-19.
