In addition to the general requirements of Article
IV, the requirements of this article shall:
A. Apply in flood hazard areas that are not identified as coastal high
hazard areas (V Zones) and Coastal A Zones. These flood hazard areas,
referred to collectively as "A Zones," include special flood hazard
areas along nontidal waters of the state, landward of coastal high
hazard areas (V Zones), and landward of Coastal A Zones (if delineated).
B. Apply to all development, new construction, substantial improvements
(including repair of substantial damage), and placement, replacement,
and substantial improvement (including repair of substantial damage)
of manufactured homes.
Within areas defined by flood protection setbacks along nontidal
waters of the state:
A. No new buildings, structures, or other development shall be permitted
unless the applicant demonstrates that the site cannot be developed
without such encroachment into the flood protection setback and the
encroachment is the minimum necessary after consideration of varying
other siting standards such as side, front, and back lot line setbacks.
B. Disturbance of natural vegetation shall be minimized and any disturbance
allowed shall be vegetatively stabilized.
C. Public works and temporary construction may be permitted.
New residential structures and residential portions of mixed-use structures, and substantial improvement (including repair of substantial damage) of existing residential structures and residential portions of mixed-use structures, shall comply with the applicable requirements of Article
IV and this section. See §
149-36 for requirements for horizontal additions.
A. Residential structures shall be elevated as follows:
(1) Lowest floors shall be elevated to or above the flood protection
elevation.
(2) In areas of shallow flooding (Zone AO), the lowest floor (including
basement) shall be elevated at least as high above the highest adjacent
grade as the depth number specified in feet on the FIRM plus two feet,
or at least four feet if a depth number is not specified.
(3) Enclosures below the lowest floor shall meet the requirements of Subsection
C.
B. Unless otherwise restricted by these regulations, especially by the limitations in §
149-33A,
B and
C, fill placed for the purpose of raising the ground level to support a building or structure shall:
(1) Consist of earthen soil or rock materials only;
(2) Extend laterally from the building footprint to provide for adequate
access as a function of use; the Floodplain Administrator may seek
advice from the State Fire Marshal's Office and/or the local
fire services agency;
(3) Comply with the requirements of the building code and be placed and
compacted to provide for stability under conditions of rising and
falling floodwaters and resistance to erosion, scour, and settling;
(4) Be sloped no steeper than one vertical to two horizontal, unless
approved by the Floodplain Administrator;
(5) Be protected from erosion associated with expected velocities during
the occurrence of the base flood; unless approved by the Floodplain
Administrator, fill slopes shall be protected by vegetation if the
expected velocity is less than five feet per second, and by other
means if the expected velocity is five feet per second or more; and
(6) Be designed with provisions for adequate drainage and no adverse
effect on adjacent properties.
C. Enclosures below the lowest floor shall:
(1) Be used solely for parking of vehicles, building access, crawl/underfloor
spaces, or limited storage.
(2) Be constructed using flood-damage-resistant materials.
(3) Be provided with flood openings which shall meet the following criteria
(NOTE: See NFIP Technical Bulletin No. 1, "Openings in Foundation
Walls and Walls of Enclosures Below Elevated Buildings."):
(a)
There shall be a minimum of two flood openings on different
sides of each enclosed area; if a building has more than one enclosure
below the lowest floor, each such enclosure shall have flood openings
on exterior walls.
(b)
The total net area of all flood openings shall be at least one
square inch for each square foot of enclosed area (nonengineered flood
openings), or the flood openings shall be engineered flood openings
that are designed and certified by a licensed professional engineer
to automatically allow entry and exit of floodwaters; the certification
requirement may be satisfied by an individual certification or an
evaluation report issued by the ICC Evaluation Service, Inc.
(c)
The bottom of each flood opening shall be one foot or less above
the higher of the interior floor or grade, or the exterior grade,
immediately below the opening.
(d)
Any louvers, screens or other covers for the flood openings
shall allow the automatic flow of floodwaters into and out of the
enclosed area.
(e)
If installed in doors, flood openings that meet requirements of Subsections
C(3)(a) through
(d) are acceptable; however, doors without installed flood openings do not meet the requirements of this section.