Sec. 3-1519 and 3-1520

Accessory structures in the SFHA shall comply with the elevation requirements and other requirements of 3-1520(B), or if not elevated or dryproofed shall be limited to no more than 600 square feet in total floor area.

Accessory structures shall not be used for human habitation; be usable only for parking of vehicles or limited storage; be constructed with flood damage-resistant materials; be anchored to prevent flotation; have electrical service and mechanical equipment elevated to or above the base flood elevation; and be provided with flood openings.

New construction and substantial improvements shall be according to the VA USBC, and anchored to prevent flotation, collapse or lateral movement of the structure.

The flood carrying capacity within an altered or relocated portion of any watercourse shall be maintained.

Provide a minimum of two openings on different sides of each enclosed area subject to flooding. The total net area of all openings must be at least one square inch for each square foot of enclosed area subject to flooding. The bottom of all required openings shall be no higher than one foot above the adjacent grade.

New construction and substantial improvements shall be constructed with materials and utility equipment resistant to flood damage.

Manufactured homes shall be anchored to prevent flotation, collapse, or lateral movement.

New construction or substantial improvements shall be constructed by methods and practices that minimize flood damage.

Buildings located in all A1—30, AE, and AH zones may be flood-proofed in lieu of being elevated provided that all areas of the building components below the elevation corresponding to the BFE plus two feet are water tight.

New construction or substantial improvement of any commercial, industrial, or non-residential building (or manufactured home) shall have the lowest floor, including basement, elevated to or above the base flood level plus 18 inches.

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 eighteen (18) inches.

New and replacement sanitary sewage systems shall be designed to minimize or eliminate infiltration of flood waters into the systems and discharges from the systems into flood waters.

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.

Fully enclosed areas below the regulatory flood protection elevation shall 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.

On-site waste disposal systems shall be located and constructed to avoid impairment to them or contamination from them during flooding.

New and replacement water supply systems shall be designed to minimize or eliminate infiltration of flood waters into the system.

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.

The floodplain districts described above shall be overlays to the existing underlying districts as shown on the official zoning ordinance map, and as such, the provisions for the floodplain districts shall serve as a supplement to the underlying district provisions.