Alexandria, VA Hurricane Preparedness: Flood Elevation (2026)

Alexandria's Zoning Ordinance regulates construction inside the FEMA-mapped floodplain under Article VI, Sec. 6-300 (Floodplain district), enforced by the city's floodplain administrator in the Department of Transportation and Environmental Services (T&ES). Sec. 6-307(A) requires that any new or substantially improved residential building, plus its extensions and accessory structures, sited in Zone A or Zone AE have its lowest floor, including any basement, elevated to or above the base flood elevation (BFE) plus one foot. No building permit for a substantial improvement to an existing residential structure may be issued unless that one-foot freeboard standard is met.

Non-residential buildings face the same BFE-plus-one-foot elevation rule under Sec. 6-307(B)(1), but may instead be dry-floodproofed with watertight walls and flood-resistant materials up to that same elevation, certified by a registered professional engineer or architect. 2-percent annual chance flood elevation, whichever is greater. Any fully enclosed space below the required elevation, including areas used only for parking, storage, or building access, must be built of flood damage-resistant materials and include at least two automatic flood vents sized to one square inch of opening per square foot of enclosed area, per Sec.

6-307(C). Mechanical, electrical, and plumbing equipment must likewise sit at or above BFE plus one foot. Every application must include a certification from a licensed architect or engineer confirming the design meets these anchoring, materials, and elevation standards before a permit issues.