Sec. 106-353

Other

• Anchoring of new construction and substantial improvements

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

• Breakaway wall design safe loading resistance20 psf

  a breakaway wall shall have a design safe loading resistance of not less than ten and no more than 20 pounds per square foot.

• Adequate drainage paths around structures on slopes

  Adequate drainage paths around structures on slopes shall be provided to guide floodwaters around and away from proposed structures.

• Bottom of required openings above adjacent grade1 ft

  The bottom of all required openings shall be no higher than one foot above the adjacent grade.

• Total net area of openings in enclosed areas below regulatory flood protection elevation1 sqin/sqftsq 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.

• Use of enclosed space below lowest floor

  The enclosed space below the lowest floor shall be used solely for parking of vehicles, building access, or storage. Such space shall not be partitioned into multiple rooms, temperature-controlled, or used for human habitation.

• Use of space below regulatory flood protection elevation

  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 used in connection with the premises.

• Use of fillGrading (cut & fill)Reshaping land by removing earth (cut) or adding it (fill), often capped by volume. for structural support prohibitedProhibitedNot allowed in the district at all, short of rezoning or a variance.

  The use of fill for structural support of buildings is prohibited.

• Construction methods to minimize flood damage

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

• Flood-resistant materials for new construction and substantial improvements

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

• Floodproofing certification by registered professional engineer or architect

  A registered professional engineer or architect shall certify that the standards of this subsection are satisfied.

• Maximum increase in base flood elevation due to development1 ft

  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 or AH on the FIRM, unless it is demonstrated that the cumulative effect of the proposed development, when combined with all other existing and anticipated development, will not increase the water surface elevation of the base flood more than one foot at any point within the county.

• Lowest floor elevation above base flood level2 ft

  the lowest floor shall be elevated to two feet above the base flood level.

• Lowest floor elevation above highest adjacent grade (AO zone, no depth number)2 ft

  the lowest floor, including basement, shall be elevated no less than two feet above the highest adjacent grade.

• Bottom of lowest horizontal structural member elevation above base flood level (Coastal A and VE zones)2 ft

  the bottom of the lowest horizontal structural member of the lowest floor (excluding the pilings or columns) is elevated to two feet above the base flood level if the lowest horizontal structural member is parallel to the direction of wave approach or elevated at least two feet above the base flood level if the lowest horizontal structural member is perpendicular to the direction of wave approach

• Anchoring of manufactured homesManufactured homeA dwelling built in a factory to a federal standard and transported to the site.

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

• New construction location relative to mean high tide

  All new construction shall be located landward of the reach of mean high tide.

• Oil and propane tank elevation above base flood elevation3 ft

  All new, replaced, or existing oil, and propane tanks must be anchored against flotation, collapse and lateral movement under flood conditions by means of an approved anchorage system or shall be installed a minimum of three feet above base flood elevation

• On-site waste disposal systems located to avoid impairment

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

• Maximum days recreational vehicle may be on site without meeting manufactured homeManufactured homeA dwelling built in a factory to a federal standard and transported to the site. requirements180 days

  Be on the site for fewer than 180 consecutive days, be fully licensed and ready for highway use

• Manmade alteration of sand dunes prohibitedProhibitedNot allowed in the district at all, short of rezoning or a variance.

  The manmade alteration of sand dunes, which would increase potential flood damage, is prohibited.

• Sanitary sewage systems designed to minimize floodwater infiltration

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

• Electrical, heating, ventilation, plumbing and air conditioning equipment elevation above base flood elevation2 ft

  Electrical, heating, ventilation, plumbing and air conditioning and other service equipment shall be elevated to a minimum of two feet above the base flood elevation.

• Structural design certification by registered professional engineer or architect

  A registered professional engineer or architect shall develop or review the structural design, specifications and plans for the construction, and shall certify that the design and methods of construction to be used are in accordance with accepted standards of practice

• Subdivision size requiring base flood elevation data5 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 comparable to those contained in a FIS 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 size (lots) requiring base flood elevation data50 lots

  Base flood elevation data shall be obtained from other sources or developed using detailed methodologies comparable to those contained in a FIS 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 to reduce flood exposure

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

• Subdivision proposals consistent with minimizing flood damage

  All subdivision proposals shall be consistent with the need to minimize flood damage

• Subdivision utilities located to minimize flood damage

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

• Substantial improvement threshold50 pct

  The modification, alteration, repair, reconstruction, or improvement of any kind to a structure and/or use, regardless of its location in a floodplain area to an extent or amount of 50 percent or more of its market value shall be undertaken only in full compliance with this article

• Water supply systems designed to minimize floodwater infiltration

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

• Permit required for alteration or relocation of watercourse

  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

• Flood carrying capacity of altered or relocated watercourse maintained

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