In addition to the general requirements of Article IV, the requirements of this article apply to all development proposed in special flood hazard areas other than coastal high-hazard areas. These areas include Zones AE and AO.
A.
Elevation requirements.
(1)
The lowest floor (including basement) shall be elevated to or above
the base flood elevation plus 18 inches.
(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 Flood Insurance
Rate Map plus 18 inches, or at least two feet plus 18 inches if a
depth number is not specified; adequate drainage paths shall be provided
to guide floodwaters around and away from the structure.
B.
Enclosures below the lowest floor.
(1)
Enclosures below the lowest floor shall be used solely for parking
of vehicles, building access, crawlspaces, or limited storage.
(2)
Enclosures below the lowest floor shall be constructed using flood-damage-resistant
materials. See FEMA Technical Bulletin No. 2, Flood Damage-Resistant
Materials Requirements.
(3)
Enclosures below the lowest floor (including crawlspaces) shall be
provided with flood openings which shall meet the following criteria
(see FEMA Technical Bulletin No. 1, Openings in Foundation Walls and
Walls of Enclosures):
(a)
There shall be a minimum of two openings on different sides
of each enclosed area; if a building has more than one enclosed area
below the base flood elevation, each area shall have openings on exterior
walls.
(b)
The total net area of all openings shall be at least one square
inch for each square foot of enclosed area, or the openings shall
be designed and certified by a registered engineer or architect to
provide for equalization of hydrostatic flood forces on exterior walls
by allowing for the automatic entry and exit of floodwaters.
(c)
The bottom of each opening shall be one foot or less above the
adjacent ground level.
(d)
Any louvers, screens or other opening covers shall allow the
automatic flow of floodwaters into and out of the enclosed area.
(e)
Where installed in doors and windows, openings that meet the requirements of § 453-26B(3)(a) through (d) are acceptable; however, doors and windows without installed openings do not meet the requirements of this section.
(4)
Crawlspaces shall have the finished interior ground level equal to
or higher than the outside finished ground level on at least one entire
side of the foundation wall.
A.
Elevation requirements.
(1)
The lowest floor (including basement) shall be elevated to or above the base flood elevation plus 18 inches or the structure shall be dry floodproofed in accordance with § 453-27B.
(2)
In areas of shallow flooding (Zone AO), if not dry floodproofed,
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 Flood Insurance Rate Map plus 18 inches, or at least
two feet plus 18 inches if a depth number is not specified; adequate
drainage paths shall be provided to guide floodwaters around and away
from the structure.
B.
Dry floodproofing requirements. Dry floodproofed structures, together
with attendant utility and sanitary facilities, shall:
(1)
Be designed to be dry floodproofed such that the structure is watertight
with walls and floors substantially impermeable to the passage of
water to the level of the base flood elevation plus 18 inches. In
areas of shallow flooding (Zone AO), the structure shall be dry floodproofed
at least as high above the highest adjacent grade as the depth number
specified in feet on the Flood Insurance Rate Map plus 18 inches,
or at least two feet plus 18 inches if a depth number is not specified.
(2)
Have structural components capable of resisting hydrostatic and hydrodynamic
loads and effects of buoyancy.
(3)
Be certified by a licensed professional engineer or licensed professional
architect, with a floodproofing certificate, that the design and methods
of construction meet the requirements of this section. Refer to FEMA
Technical Bulletin No. 3, Non-Residential Floodproofing - Requirements
and Certification, for guidance.
[Amended 8-21-2015 by Ord. No. 517; 11-17-2017 by Ord. No. 537]
A.
Accessory structures shall meet the requirements of these regulations.
Accessory structures that have a footprint of no more than 150 square
feet may be allowed without requiring elevation or floodproofing,
provided such structures meet all of the following requirements: