Sec. 4.12.8

Other

• Existing structure conformity

  Any structure or use of a structure or premises must be brought into conformity with these provisions when it is changed, repaired, or improved unless one of the exceptions is established.

• Flood openings requirements

  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.

• No increase in floodway

  Within any floodway area, no new construction or development shall be permitted that would cause any increase in the base flood elevation.

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

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

• No increase in base flood elevation

  No new construction or development shall be permitted within the floodplain overlay district unless it is demonstrated through hydrologic and hydraulic analysis performed in accordance with standard engineering practice that the cumulative effect of the proposed development, when combined with all other existing and anticipated development will not increase the elevation of the base flood.

• Nonresidential lowest floor elevation1 ft above BFE

  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. Nonresidential buildings located in all AE, AH and A zones with detailed base flood elevations may be flood-proofed in lieu of being elevated provided that all areas of the building components below the elevation corresponding to the base flood elevation plus one foot are water tight.

• Recreational vehicle standard

  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 lowest floor elevation1 ft above BFE

  New construction or substantial improvement of any residential structure (including manufactured homes) in zones 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 one foot.

• Space below lowest floor restrictions

  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.

• Base flood elevation data for large subdivisions

  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 lots or five acres, whichever is the lesser.

• Subdivision drainage

  All subdivision proposals shall have adequate drainage provided to reduce exposure to flood hazards.

• Subdivision public utilitiesPublic utilitiesInfrastructure serving the wider area — substations, pump stations, towers.

  All subdivision proposals shall have public utilities and facilities such as sewer, gas, electrical and water systems located and constructed to minimize flood damage.

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

  Variances shall be issued only upon a showing of good and sufficient cause, exceptional hardship, and no unacceptable increases in flood heights, threats to public safety, or extraordinary public expense.

• Permit for alteration of waterways

  Prior to any proposed alteration or relocation of any channels or of any watercourse, stream, etc., within the Town of Purcellville, a permit shall be obtained from the U.S. Corps of Engineers, the Virginia Department of Environmental Quality, and the Virginia Marine Resources Commission.

• Zoning permit required

  All uses, activities and development, including placement of manufactured homes, occurring within the floodplain overlay district shall be undertaken only upon the issuance of a zoning permit.