A.
Permit requirement. All uses, activities, and development occurring
within any floodplain district, including placement of manufactured
homes, shall be undertaken only upon the issuance of a building and/or
zoning permit. Such development shall be undertaken only in strict
compliance with the provisions of this chapter and with all other
applicable codes and ordinances, as amended, such as the Virginia
Uniform Statewide Building Code (VA USBC), the Mathews County Zoning
Ordinance[1] and the Mathews County Subdivision Regulations.[2] Prior to the issuance of any such permit, the Floodplain
Administrator shall require all applications to include compliance
with all applicable state and federal laws and shall review all sites
to assure they are reasonably safe from flooding. Under no circumstances
shall any use, activity, and/or development adversely affect the capacity
of the channels or floodways of any watercourse, drainage ditch, or
any other drainage facility or system.
B.
Site plans and permit applications. All applications for development
within any floodplain district and all building permits issued for
the floodplain shall incorporate the following information:
(1)
The elevation of the base flood at the site.
(2)
The elevation of the lowest floor (including basement) or in VE or
V Zones the lowest horizontal structural member.
(3)
For structures to be floodproofed (nonresidential only), the elevation
to which the structure will be floodproofed.
(4)
Topographic information showing existing and proposed ground elevations.
A.
The following provisions shall apply to all permits:
(1)
New construction and substantial improvements shall be according
to the VA USBC, and anchored to prevent flotation, collapse or lateral
movement of the structure.
(2)
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
anchoring requirements for resisting wind forces.
(3)
New construction and substantial improvements shall be constructed
with materials and utility equipment resistant to flood damage.
(4)
New construction or substantial improvements shall be constructed
by methods and practices that minimize flood damage.
(5)
Electrical, heating, ventilation, plumbing, air-conditioning equipment
and other service facilities, including duct work, shall be located
above the base flood elevation or designed so as to prevent water
from entering or accumulating within the components during conditions
of flooding.
(6)
New and replacement water supply systems shall be designed to minimize
or eliminate infiltration of floodwaters into the system.
(7)
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.
(8)
On-site waste disposal systems shall be located and constructed to
avoid impairment to them or contamination from them during flooding.
B.
In addition to provisions in A(1) through (8) above, in all special
flood hazard areas, the additional provisions shall apply:
(1)
Prior to any proposed alteration or relocation of any channels or
of any watercourse, stream, etc., within this jurisdiction a permit
shall be obtained from the United States Corps of Engineers, the Virginia
Department of Environmental Quality, and the Virginia Marine Resources
Commission. (A joint permit application is available from any of these
organizations.) Furthermore, in riverine areas, notification of the
proposal shall be given by the applicant to all affected adjacent
jurisdictions, the Department of Conservation and Recreation (Division
of Dam Safety and Floodplain Management), other required agencies,
and the Federal Emergency Management Agency.
(2)
The flood-carrying capacity within an altered or relocated portion
of any watercourse shall be maintained.
In all identified flood hazard areas where base flood elevations have been provided in the FIS or generated by a certified professional in accordance with § 63-15C, the following provisions shall apply:
A.
Residential construction. New construction or substantial improvement of any residential structure (including manufactured homes) in Zones AE and A with detailed base flood elevations shall have the lowest floor, including basement, elevated to or above the base flood elevation (BFE), and, in VE Zones, shall have the lowest horizontal structural member elevated to or above the base flood elevation (BFE), per Article III, § 63-15C(4).
B.
Nonresidential construction. New construction or substantial improvement
of any commercial, industrial, or nonresidential building (or manufactured
home) shall have the lowest floor, including basement, elevated to
or above the base flood elevation (BFE). Buildings located in all
AE Zones may be floodproofed in lieu of being elevated, provided that
all areas of the building components below the elevation corresponding
to the BFE are watertight with walls substantially impermeable to
the passage of water, and use structural components having the capability
of resisting hydrostatic and hydrodynamic loads and the effect of
buoyancy. A registered professional engineer or architect shall certify
that the standards of this subsection are satisfied. Such certification,
including the specific elevation (in relation to mean sea level) to
which such structures are floodproofed, shall be maintained by the
Floodplain Administrator.
C.
Space below the lowest floor. In Zones A and AE, fully enclosed areas,
of new construction or substantially improved structures, which are
below the regulatory flood protection elevation (BFE) shall:
(1)
Not be designed or used for human habitation, but shall only be used
for parking of vehicles, building access, or limited storage of maintenance
equipment used in connection with the premises. Access to the enclosed
area shall be the minimum necessary to allow for parking of vehicles
(garage door) or limited storage of maintenance equipment (standard
exterior door), or entry to the living area (stairway or elevator).
(2)
Be constructed entirely of flood-resistant materials below the regulatory
flood protection elevation (base flood elevation);
(3)
Include measures to automatically equalize hydrostatic flood forces
on walls by allowing for the entry and exit of floodwaters. To meet
this requirement, the openings must either be certified by a professional
engineer or architect or meet the following minimum design criteria:
(a)
Provide a minimum of two openings on different sides of each
enclosed area subject to flooding.
(b)
The total net area of all openings must be at least one square
inch for each square foot of enclosed area subject to flooding.
(c)
If a building has more than one enclosed area, each area must
have openings to allow floodwaters to automatically enter and exit.
(d)
The bottom of all required openings shall be no higher than
one foot above the adjacent grade.
(e)
Openings may be equipped with screens, louvers, or other opening
coverings or devices, provided they permit the automatic flow of floodwaters
in both directions.
(f)
Foundation enclosures made of flexible skirting are not considered
enclosures for regulatory purposes, and, therefore, do not require
openings. Masonry or wood underpinning, regardless of structural status,
is considered an enclosure and requires openings as outlined above.
D.
Standards for manufactured homes and recreational vehicles.
(2)
All recreational vehicles placed on sites must either:
(a)
Be on the site for fewer than 180 consecutive days, be fully
licensed and ready for highway use (A recreational vehicle is ready
for highway use if it is on its wheels or jacking system, is attached
to the site only by quick-disconnect-type utilities and security devices
and has no permanently attached additions.); or
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 minimize flood damage;
C.
All subdivision proposals shall have adequate drainage provided to
reduce exposure to flood hazards; and
D.
Base flood elevation data shall be obtained from other sources or
developed using detailed methodologies, hydraulic and hydrologic analysis,
comparable to those contained in a Flood Insurance Study for subdivision
proposals and other proposed development proposals (including manufactured
home parks and subdivisions) that exceed 50 lots or five acres, whichever
is the lesser.
