D.1

Floodplain

• Access driveway elevation

  All new construction and substantial improvements to existing structures shall have the access driveways elevated to at least the base flood elevation.

• Anchoring

  All new construction and substantial improvements to existing structures shall be anchored to prevent flotation, collapse or lateral movement of the structure, constructed with materials and utility equipment that are resistant to flood damage, and constructed by methods and practices that minimize flood damage.

• Approximated floodplainFloodplainLand expected to flood at a stated frequency, where building carries extra conditions. prohibitedProhibitedNot allowed in the district at all, short of rezoning or a variance.

  In the approximated floodplain district, all development and uses shall be the same as permitted in the floodway district.

• Dam break inundation zones

  Reasonable consideration shall be given to protect life and property in mapped dam break inundation zones against impounding structure failure, in accordance with state law.

• Elevation certificate

  Prior to issuance of a certificate of occupancy for any single family dwelling on a lot or parcel which is located, in whole or in part, on a FEMA floodplain, the owner of the lot or parcel shall obtain and file an elevation certificate for the lot with the Director of Environmental Engineering.

• Existing structures

  The modification, alteration, repair, reconstruction or improvement of any kind to a structure and/or use requiring a building permit located in any Special Flood Hazard Area district, to an extent or amount of less than 50% of its value, shall be elevated to the greatest extent possible and conform to the Virginia Uniform Statewide Building Code.

• Floodway expansion

  Existing structures in the floodway district shall not be expanded or enlarged unless it has been demonstrated through hydrologic and hydraulic analyses performed in accordance with standard engineering practices that the proposed expansion would not result in any increase in the base flood elevation.

• No increase in base flood elevation

  In the floodway fringe district, the development and/or use of land shall be permitted in accordance with the regulations of the underlying zoning district, but all such uses, activities and/or development shall not increase the base flood elevation.

• Floodway fringe permitted uses

  Permitted uses: Nonresidential construction, subject to the provisions of Subsection D.1.g. Accessory structures, subject to the provisions of Subsection D.1.d. Golf courses.

• Floodway prohibitedProhibitedNot allowed in the district at all, short of rezoning or a variance. development

  The following shall be prohibited in the floodway district: structures, substantial improvements, manufactured homes, fill or other development.

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

  All existing manufactured homes (in parks or on individual lots/parcels) located in the base flood area shall be anchored to resist flotation, collapse or lateral movement by providing over-the-top and frame ties to ground anchors.

• Manufactured homeManufactured homeA dwelling built in a factory to a federal standard and transported to the site. elevation above grade3 ft

  All such manufactured homes shall be located no less than three feet above grade, provided that no manufactured home at the same site has sustained substantial damage from a flood.

• Minimum lowest floor elevation1 ft

  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 a minimum of one foot above the base flood level.

• New manufactured homeManufactured homeA dwelling built in a factory to a federal standard and transported to the site. lowest floor elevation1 ft

  the lowest floor of the home will be at least one foot above the base flood elevation of the nearest A zone

• New manufactured homeManufactured homeA dwelling built in a factory to a federal standard and transported to the site. setbackSetbackThe distance a building must be held back from a lot line. from base flood25 ft

  The placement of new manufactured homes on individual lots or parcels adjacent to the base flood area ... shall require that: stands or lots be elevated on compacted fill or on pilings so that the lowest floor of the home will be at least one foot above the base flood elevation of the nearest A zone and be set back at least 25 feet horizontal distance from the outermost boundary of the base flood

• No filling without approval

  There shall be no filling of any floodplain unless approved by the Director of Environmental Engineering and an approved land disturbance permit, building permit, improvement sketch, subdivision or site plan is on file with the Department of Environmental Engineering.

• No filling to make building lot

  Filling in the base flood area shall be prohibited to make a building lot for the purpose of constructing a residential dwelling unless permitted by a variance issued by the Director of Environmental Engineering.

• Nonresidential floodproofing elevation1 ft

  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 a minimum of one foot above the base flood level.

• On-site waste disposal

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

• Permit required

  All uses, activities and development occurring within any floodplain district shall be undertaken only after the issuance of a land disturbance and/or building permit.

• Recreational vehicles

  All recreational vehicles placed on sites must either be on the site for fewer than 180 consecutive days, be fully licensed and ready for highway use, or meet all the requirements for manufactured homes.

• Residential dwelling on 95% inundated parcel

  One residential dwelling is permitted on each parcel that was recorded as of March 16, 1983, that is at least 95% inundated by the base flood and that is located within the base flood, provided it shall have a minimum floor level, including basement, of one foot above the base flood and cause no increase in the base flood elevation.

• Residential setbackSetbackThe distance a building must be held back from a lot line. from base flood area25 ft

  All new construction and substantial improvements of residential dwellings adjacent to the base flood area/backwater shall be set back at least 25 feet horizontal distance from the outermost boundary of the base flood area/backwater

• Sanitary sewage systems

  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.

• Subdivision base flood data

  All subdivision proposals and other proposed new developments shall include, within such proposals, base flood elevation data.

• Substantial improvement elevation1 ft

  A residential structure that receives substantial improvement shall be elevated to at least one foot above the base flood elevation.

• Nonresidential setbackSetbackThe distance a building must be held back from a lot line. in Upper Swift Creek25 ft

  Within the Upper Swift Creek Watershed all new construction and substantial improvements of nonresidential structures and accessory buildings shall be located outside the floodway fringe and shall be set back at least 25 feet horizontal distance from the outermost boundary of the base flood area, wetlands, Resource Protection Areas and 100-year floodplains where the contributing drainage area exceeds 100 acres

• Nonresidential setbackSetbackThe distance a building must be held back from a lot line. with LID in Upper Swift Creek5 ft

  provided however, that when LID practices, as determined by the Director of Environmental Engineering, are used adjacent to wetlands, floodplains and Resource Protection Areas, the setback may be reduced to five feet.

• Upper Swift Creek prohibitedProhibitedNot allowed in the district at all, short of rezoning or a variance. activities

  The following shall be prohibited within the Upper Swift Creek Watershed 100-year floodplains when the contributing drainage area exceeds 100 acres in size: clear cutting; removal of tree stumps; clearing of vegetation; filling; grading; placement of fences or other appurtenant structures.

• Residential setbackSetbackThe distance a building must be held back from a lot line. in Upper Swift Creek35 ft

  In the Upper Swift Creek Watershed, all new construction of and substantial improvements to residential dwellings shall be setback at least 35 feet horizontal distance from the outermost boundary of the 100-year floodplain where the contributing drainage area exceeds 100 acres.

• Utilities elevation1 ft

  All electric water heaters, electric furnaces and other critical electrical installations shall be permitted only at elevations at least one foot above the base flood elevation.

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

  Variances may be issued by the Director of Environmental Engineering for new construction and substantial improvements to be erected on a lot of one-half acre or less in size contiguous to and surrounded by lots with existing structures constructed below the base flood level, in conformance with the provisions of this Section.

• Water supply systems

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