Section 714.09

Floodplain

• Approximated FloodplainFloodplainLand expected to flood at a stated frequency, where building carries extra conditions. ingress/egress width15 ft

  The means of pedestrian ingress and egress shall be a minimum of fifteen (15) feet wide, or five (5) feet wide if equipped with handrails or other safety features.

• Approximated FloodplainFloodplainLand expected to flood at a stated frequency, where building carries extra conditions. lowest floor elevation above BFE1 ft

  The lowest floor shall be elevated to or above the base flood level of one (1) foot above base-flood elevation.

• Approximated FloodplainFloodplainLand expected to flood at a stated frequency, where building carries extra conditions. manufactured homeManufactured homeA dwelling built in a factory to a federal standard and transported to the site. elevation1 ft

  The lowest floor of the manufactured home is elevated no lower than one (1) foot above the base flood elevation; or no less than 36 inches above grade; or the manufactured home chassis is supported by reinforced piers... of no less than one (1) foot above base flood elevation.

• Enclosed area flood openings1 sq_in_per_sq_ft

  Provide a minimum of two (2) openings on different sides of each enclosed area subject to flooding. The total net area of all openings must be at least one (1) square inch for each square foot of enclosed area subject to flooding. The bottom of all required openings shall be no higher than one (1) foot above the adjacent grade.

• Enclosed area below flood protection elevation 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 only be used for parking of vehicles, building access, or limited storage of maintenance equipment.

• Floodway base flood elevation increase limit1 ft

  The Floodway District (FW) is delineated... using the criteria that a certain area within the flood plain must be capable of carrying the waters of the one hundred (100) year flood without increasing the water surface elevation of that flood more than one (1) foot at any point.

• Floodway encroachment prohibition

  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 during the occurrence of the base flood discharge.

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

  The placement of manufactured homes is prohibited, except in an existing manufactured home park. A replacement manufactured home may be placed on a lot provided anchoring, elevation, and encroachment standards are met.

• ProhibitedProhibitedNot allowed in the district at all, short of rezoning or a variance. uses in Floodway DistrictZoning districtA mapped area with one set of rules, identified by a code like R-1 or B-2.

  Structures designed or used for human habitation; storage or processing of pollutants, buoyant, flammable, poisonous, or explosive materials; garbage and waste disposal facilities; placement of fill material; permanent structures.

• Non-residential lowest floor elevation above BFE1 ft

  New construction or substantial improvement of any commercial, industrial, or non-residential building shall have the lowest floor, including basement, elevated one (1) foot above base-flood elevation.

• Recreational vehicle 180-day limit180 days

  All recreational vehicles placed on sites must: Be on the site for fewer than one hundred eighty (180) consecutive days; Be fully licensed and ready for highway use... or Meet all the applicable building code requirements for manufactured homes.

• Residential lowest floor elevation above BFE1 ft

  New construction or substantial improvement of any residential structure, including manufactured homes, shall have the lowest floor, including basement, elevated one (1) foot above base-flood elevation.

• Special FloodplainFloodplainLand expected to flood at a stated frequency, where building carries extra conditions. DistrictZoning districtA mapped area with one set of rules, identified by a code like R-1 or B-2. development 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, designated as Zones A1-30 and AE on the Flood Insurance Rate Map.

• Special FloodplainFloodplainLand expected to flood at a stated frequency, where building carries extra conditions. DistrictZoning districtA mapped area with one set of rules, identified by a code like R-1 or B-2. base flood elevation increase limit1 ft

  Development activities in Zones A1-30, AE, and AH... which increase the water surface elevation of the base flood by more than one (1) foot may be allowed, provided that the applicant first applies... for a conditional Flood Insurance Rate Map revision.

• Storage of hazardous materials elevation above flood protection elevation1 ft

  Storage of materials that are pollutants, buoyant, flammable, explosive, or which otherwise could be injurious... shall be stored one (1) foot above the flood protection elevation, flood-proofed, or protected by structural measures.

• Subdivision BFE data requirement threshold5 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 fifty (50) lots or five (5) acres, whichever is the lesser.

• Substantial damage threshold50 pct

  Substantial damage. Damage of any origin sustained by a structure when the cost of restoring the structure to its before damaged condition would equal or exceed fifty (50) percent of the market value of the structure before the damage occurred.

• Substantial improvement threshold50 pct

  Substantial improvement. Any reconstruction, rehabilitation, addition, or other improvement of a structure, the cost of which equals or exceeds fifty (50) percent of the market value of the structure before the start of construction of the improvement.

• VarianceVariancePermission to depart from a specific dimensional rule, granted on a showing of hardship. prohibition for accessoryAccessory useA secondary activity customarily incidental to the main use of the lot — a garage, a home office. structures in SFHA

  Variances will not be issued for any accessory structure within the SFHA.

• Watercourse alteration permit required

  Prior to any proposed alteration or relocation of any channels or of any watercourse in a special flood hazard area, a permit shall be obtained from the U.S. Corps of Engineers, the Virginia Department of Environmental Quality, and the Virginia Marine Resources Commission.