§ 19.6-76.3.1, § 19.6-76.4.2, § 19.6-76.4.3

Floodplain

• A Zone base flood elevation determination

  Where the specific one-percent-annual-chance flood elevation cannot be determined for this area using other sources of data... then the applicant for the proposed use, development and/or activity shall determine this base flood elevation.

• AccessoryAccessory useA secondary activity customarily incidental to the main use of the lot — a garage, a home office. structure size limit in SFHA600 sqftsq ftSquare feet. An acre is 43,560 sq ft; a typical suburban lot is 7,000–10,000.

  Accessory structures in the SFHA shall comply with the elevation requirements and other requirements of this article or, if not elevated or dry floodproofed, shall: ... Be limited to no more than 600 square feet in total floor area; ... Be useable only for parking of vehicles or limited storage; ...

• AE/AH zone encroachment restriction

  Until a regulatory floodway is designated, no new construction, substantial improvements, or other development (including fill) shall be permitted within the areas of special flood hazard... unless it is demonstrated that the cumulative effect of the proposed development... will not increase the water surface elevation of the base flood more than one foot at any point within Appomattox County.

• AO Zone non-residential elevation2 ft

  All new construction and substantial improvements of non-residential structures shall: Have the lowest floor, including basement, elevated to or above the flood depth specified on the FIRM... If no flood depth number is specified, the lowest floor, including basement, shall be elevated at least two feet above the highest adjacent grade; or... be completely floodproofed to the specified flood level...

• AO Zone residential elevation2 ft

  All new construction and substantial improvements of residential structures shall have the lowest floor, including basement, elevated to or above the flood depth specified on the FIRM, above the highest adjacent grade at least as high as the depth number specified in feet on the FIRM. If no flood depth number is specified, the lowest floor, including basement, shall be elevated no less than two feet above the highest adjacent grade.

• Flood opening requirements1 sq inch per sq ftsq ftSquare feet. An acre is 43,560 sq ft; a typical suburban lot is 7,000–10,000.

  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.

• Floodway encroachment restriction

  Within any floodway area, no encroachments, including fill, new construction, substantial improvements, or other development shall be permitted unless it has been demonstrated through hydrologic and hydraulic analysis... that the proposed encroachment will not result in any increase in flood levels within the community during the occurrence of the base flood discharge.

• Lowest floor elevation requirement18 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 18 inches.

• Manufactured homeManufactured homeA dwelling built in a factory to a federal standard and transported to the site. prohibition in floodway

  The placement of manufactured homes (mobile homes) is prohibited, except in an existing manufactured home (mobile home) park or subdivision.

• Non-residential elevation or floodproofing18 inches

  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. Non-residential buildings located in all A1-30, AE, and AH zones may be floodproofed in lieu of being elevated...

• Recreational vehicle use restriction10 days

  All recreational vehicles placed on sites must either: Be on the site for fewer than 10 consecutive days, be fully licensed and ready for highway use...; or Meet all the requirements for manufactured homes in the Virginia Uniform Statewide Building Code (VA USBC).

• Space below lowest floor use restriction

  Fully enclosed areas, of new construction or substantially improved structures, which are below the regulatory flood protection elevation shall: 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...

• Subdivision BFE data threshold5 lots or acresacre43,560 square feet — about the size of an American football field without the end zones.

  Base flood elevation data shall be obtained from other sources or developed using detailed methodologies... for subdivision proposals and other proposed development proposals (including manufactured home parks and subdivisions) that exceed five lots or five acres, whichever is the lesser.

• Substantial improvement threshold50 pct

  The change, when added to all the changes made during a rolling five-year period does not constitute 50% of the structure's value.

• VarianceVariancePermission to depart from a specific dimensional rule, granted on a showing of hardship. accessoryAccessory useA secondary activity customarily incidental to the main use of the lot — a garage, a home office. structure size limit600 sqftsq ftSquare feet. An acre is 43,560 sq ft; a typical suburban lot is 7,000–10,000.

  No variance shall be granted for an accessory structure exceeding 600 square feet.

• VarianceVariancePermission to depart from a specific dimensional rule, granted on a showing of hardship. lot size limit0.5 acreacre43,560 square feet — about the size of an American football field without the end zones.

  Variances may be issued by the Board of Zoning Appeals for new construction and substantial improvements to be erected on a lot of 1/2 acre or less in size contiguous to and surrounded by lots with existing structures constructed below the base flood level...

• VarianceVariancePermission to depart from a specific dimensional rule, granted on a showing of hardship. prohibition in floodway

  No variance shall be granted for any proposed use, development, or activity within any Floodway District that will cause any increase in the one-percent-chance flood elevation.