In all areas of special flood hazards the following standards are required:
A.
Anchoring.
(1)
All new construction and substantial improvements shall
be anchored to prevent flotation, collapse, or lateral movement of the structure.
(2)
All manufactured homes shall be anchored to resist flotation,
collapse, or lateral movement. Methods of anchoring may include, but are not
to be limited to, use of over-the-top or frame ties to ground anchors. This
requirement is in addition to applicable state and local anchoring requirements
for resisting wind force.
B.
Construction materials and methods.
C.
Utilities.
(1)
All new and replacement water supply systems shall be
designed to minimize or eliminate infiltration of floodwaters into the system.
(2)
New and replacement sanitary sewage systems shall be
designed to minimize or eliminate infiltration of floodwaters into the systems
and discharge from the system into floodwaters.
(3)
On-site waste disposal systems shall be located to avoid
impairment to them or contamination from them during flooding.
(4)
Electrical, heating, ventilation, plumbing and 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.
D.
Subdivision proposals.
(1)
All subdivision proposals shall be consistent with the
need to minimize flood damage;
(2)
All subdivision proposals shall have public utilities
and facilities such as sewer, gas, electrical and water systems located and
constructed to minimize flood damage;
(3)
All subdivision proposals shall have adequate drainage
provided to reduce exposure to flood damage; and
(4)
Base flood elevation data shall be provided for subdivision
proposals and other proposed development which contain at least 50 lots or
5 acres (whichever is less).
E.
Enclosure openings. For all new construction and substantial
improvements, fully enclosed areas below the lowest floor that are subject
to flooding shall be designed to automatically equalize hydrostatic flood
forces on exterior walls by allowing for the entry and exit of floodwaters.
Designs for meeting this requirement must either be certified by a registered
professional engineer or architect or must meet or exceed the following minimum
criteria: 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 openings shall be no higher than one
foot above grade. Openings may be equipped with screens, louvers, or other
coverings or devices, provided that they permit the automatic entry and exit
of floodwaters.
In all areas of special flood hazards where base flood elevation data have been provided as set forth in § 81-7, Basis for establishing areas of special flood hazard, or in § 81-14C(2), Use of other base flood data, the following standards are required:
A.
Residential construction. New construction and substantial
improvement of any residential structure shall have the lowest floor, including
basement, elevated to at least one foot above base flood elevation.
B.
Nonresidential construction. New construction and substantial
improvement of any commercial, industrial or other nonresidential structure
shall either have the lowest floor, including basement, elevated to at least
one foot above base flood elevation or, together with attendant utility and
sanitary facilities, shall:
(1)
Be floodproofed so that below the base flood level the
structure is watertight with walls substantially impermeable to the passage
of water;
(2)
Have structural components capable of resisting hydrostatic
and hydrodynamic loads and effects of buoyancy; and
(3)
Be certified by a registered professional engineer or architect that the design and methods of construction are in accordance with accepted standards of practice for meeting the applicable provisions of this subsection. Such certification shall be provided to the official as set forth in § 81-14C(3)(b).
C.
Manufactured homes. All manufactured homes to be placed
or substantially improved within an area of special flood hazard shall be
elevated on a permanent foundation such that the top of the lowest floor is
at or above the base flood elevation.
Located within areas of special flood hazard established in § 81-7 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 erosion potential, the following provisions apply:
A.
Encroachments are prohibited, including fill, new construction,
substantial improvements, and other development unless a technical evaluation
demonstrates that encroachments shall not result in any increase in flood
levels during the occurrence of the base flood discharge.
C.
The placement of any mobile homes is prohibited.
