Sec. 83-422 - Establishment of floodplain overlay districts
Dimensional standards
Servicing
- Geographic extent
- Areas of special flood hazard as shown on the Flood Insurance Rate Map (FIRM) and Flood Insurance Study (FIS) for Powhatan County, including floodway, AE/AH, A, AO, Coastal A, VE/V zones, and mapped floodplainFloodplainLand expected to flood at a stated frequency, where building carries extra conditions. areas.
Extracted standards
16 individual requirements pulled out of this section’s prose, each with the sentence it came from.
Floodplain
- Permit required for all development in floodplainFloodplainLand expected to flood at a stated frequency, where building carries extra conditions.
All uses, activities, and development occurring within any floodplain district, including placement of manufactured homes, shall be undertaken only upon the issuance of a permit.
Other
- Breakaway walls requirements in VE/V zones
All new construction and substantial improvements shall have the space below the lowest floor either free of obstruction or constructed with non-supporting breakaway walls, open wood-lattice work, or insect screening intended to collapse under wind and water loads without causing structural damage. Breakaway walls shall have a design safe loading resistance of not less than ten and no more than 20 pounds per square foot.
- Elevation on pilings or columns in VE/V zones
All new construction and substantial improvements in zones V and VE, including manufactured homes, shall be elevated on pilings or columns so that the bottom of the lowest horizontal structural member of the lowest floor is elevated to or above the base flood level plus 18 inches if parallel to wave approach or at least two feet above base flood level if perpendicular.
- No encroachments unless no increase in flood levels
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.
- 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. in VE/V zones
The use of fill for structural support of buildings is prohibited.
- Lowest floor elevated to base flood elevation plus 18 inches18 in
When such base flood elevation data is utilized, the lowest floor shall be elevated to or above the base flood level plus 18 inches.
- Lowest floor elevated to base flood elevation plus 1 foot freeboard1 ft
Buildings and structures within this zone shall have the lowest floor elevated to or above the base flood elevation plus one foot of freeboard and must comply with the provisions in section 83-422(a)(3) and section 83-423(b) and (c).
- Non-residential lowest floor elevation or floodproofing in AO zone2 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, 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 at least two feet above the highest adjacent grade; or, together with attendant utility and sanitary facilities be completely floodproofed to the specified flood level.
- Residential lowest floor elevation in AO zone2 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.
- Manufactured homesManufactured homeA dwelling built in a factory to a federal standard and transported to the site. prohibitedProhibitedNot allowed in the district at all, short of rezoning or a variance. except in existing parks
The placement of manufactured homes (mobile homes) is prohibited, except in an existing manufactured home (mobile home) park or subdivision.
- No new construction unless cumulative effect does not increase base flood elevation more than 1 foot1 ft
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, 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.
- No principal structure in floodway
No principal structure may be erected in this zone, however, structures incidental to the permitted uses are permitted (e.g., picnic shelter, etc.).
- No principal structure in AE/AH zones
No principal structure may be erected in this zone, however, structures incidental to the permitted uses are permitted (e.g., picnic shelter, etc.).
- No principal structure in A zone
No principal structure may be erected in this zone, however, structures incidental to the permitted uses are permitted (e.g., picnic shelter, etc.).
- Emergency service, medical service, or governmental records storage prohibitedProhibitedNot allowed in the district at all, short of rezoning or a variance. except by special exception
In this area no emergency service, medical service, or governmental records storage shall be allowed except by special exception using the variance process.
Overlay
- More restrictive provisions apply
If there is any conflict between the provisions or requirements of the floodplain districts and those of any underlying district, the more restrictive provisions and/or those pertaining to the floodplain districts shall apply.
From the ordinance
The various special flood hazard districts shall include the SFHAs. The basis for the delineation of these districts shall be the FIS and the FIRM for Powhatan County prepared by the Federal Emergency Management Agency, Federal Insurance Administration, dated September 26, 2024.