[44 CFR 59.22, 60.2, 60.3]
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 permit. Such
development shall be undertaken only in strict compliance with the
provisions of this Ordinance and with all other applicable codes and
ordinances, as amended, such as the Virginia Uniform Statewide Building
Code (VA USBC) and the Buchanan County Subdivision Regulations. 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 permits issued for the floodplain
shall incorporate the following information:
(1) The elevation of the base flood at the site.
(2) For structures to be elevated, the elevation of the lowest floor
(including basement).
(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 built according
to this chapter and 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 designed
and/or located 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 Subsection
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 U.S. 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; and the Federal Insurance Administrator.
(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,
the following provisions shall apply. (44 CFR 60.3):
A. Residential construction. New construction or substantial improvement
of any residential structure (including manufactured homes) in Zones
A1-30, AE, AH, and A with detailed base flood elevations shall have
the lowest floor, including basement, elevated to or above the base
flood level plus 18 inches. [NOTE: The flood maps anticipate one foot
of rise in BFE due to fill in the floodplain, so while building to
BFE is all that is required, it will result in flooding if all assumptions
made in mapping are correct. Flood insurance rounds up for freeboarded
so an eighteen-inch requirement offers the best "bang for the buck"
in reducing flood insurance rates and allows for an additional margin
of safety in case the models have an error or are based on incomplete
data.]
B. Nonresidential construction.
(1) 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 level
plus 18 inches. [NOTE: The flood maps anticipate one foot of rise
in BFE due to fill in the floodplain, so while building to BFE is
all that is required, it will result in flooding if all assumptions
made in mapping are correct. Flood insurance rounds up for freeboard
so an eighteen-inch requirement offers the best "bang for the buck"
in reducing flood insurance rates and allows for an additional margin
of safety in case the models have an error or are based on incomplete
data.]
(2) Non-residential buildings located in all A1-30, AE, and AH Zones
may be floodproofed in lieu of being elevated, provided that all areas
of the building components below the elevation corresponding to the
BFE plus two feet [NOTE: If your community has adopted the recommended
freeboard you might need to change this provision to be consistent
or higher than the freeboard otherwise required. Please note that
the minimum requirements are BFE plus one foot-two feet of freeboard
is the recommended minimum.] 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, AE, AH, AO, and A1-A30,
fully enclosed areas of new construction or substantially improved
structures which are below the regulatory flood protection elevation
shall:
(1) Not be designed or used for human habitation, but shall be used solely
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;
(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. Accessory structures.
(1) Accessory structures in the SFHA shall comply with the elevation requirements and other requirements of Article
V or, if not elevated or dry floodproofed, shall:
(a)
Not be used for human habitation;
(b)
Be limited to no more than 600 square feet [NOTE: This is the minimum size restriction set by FEMA Region III, but a community could choose a higher standard and limit accessory structures to a size less than 600 square feet. However, a variance could be issued for larger accessory structures, not to exceed 600 square feet. If a smaller size limit is chosen, additional language would be required in Article
VI: Variances - see Footnote 23. The chosen size restriction should also be reflected in Article
IV, Section 4.3.D.2.b, Article
VI, Section M, and Article VIII-Glossary in the definition of "Appurtenant or accessory structure."] in total floor area;
(c)
Be useable only for parking of vehicles or limited storage;
(d)
Be constructed with flood-damage-resistant materials below the
base flood elevation;
(e)
Be constructed and placed to offer the minimum resistance to
the flow of floodwaters;
(f)
Be anchored to prevent flotation;
(g)
Have electrical service and mechanical equipment elevated to
or above the base flood elevation;
(h)
Be provided with flood openings which shall meet the following
criteria:
[1]
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.
[2]
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.
[3]
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.
[4]
Any louvers, screens or other covers for the flood openings
shall allow the automatic flow of floodwaters into and out of the
enclosed area.
(i)
A signed declaration of land restriction (nonconversion agreement)
shall be recorded on the property deed. [NOTE: A nonconversion agreement
is strongly recommended, especially if a variance is being issued
for an accessory structure. However, the nonconversion agreement is
not a requirement.]
E. Standards for manufactured homes and recreational vehicles.
(1) In Zones A, AE, AH, and AO, all manufactured homes placed, or substantially improved, on individual lots or parcels, must meet all the requirements for new construction, including the elevation and anchoring requirements in Article
IV and Article
V.
(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
(b)
Meet all the requirements for manufactured homes in Article
V.
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 [NOTE: The recommended
standard here is five lots instead of 50. Fifty lots is the breakpoint
suggested in the federal regulations, but the 5/5 rule is less confusing
and captures more commercial development.] lots or five acres, whichever
is the lesser.