Floodplain definitions - Before getting too deeply into regulatory details of the floodplain program, it might be helpful to know what a floodplain is. Simply put, a floodplain is any land area susceptible to being inundated by water from any source. It includes the floodway and flood-fringe areas. Here are some related definitions.
Flooding or flood means
The regulatory floodway means the channel of a river or other watercourse and the adjacent land areas that must be reserved in order to discharge the base flood without cumulatively increasing the water surface elevation more than a designated height. The floodway is the most dangerous part of the floodplain. It is associated with moving water. Development is generally prohibited in floodways.
The flood-fringe is the portion of the floodplain outside of the floodway, which is covered by floodwater during the 100-year discharge. The term, "flood-fringe" is generally associated with standing rather than flowing water. It is also that part of the floodplain wherein development is subject to a community's floodplain ordinance.
Base flood means the flood having a one percent chance of being equaled or exceeded in any given year.
Floodplain management means the operation of an overall program of corrective and preventive measures for reducing flood damage, including but not limited to emergency preparedness plans, flood control works and floodplain management regulations.
Special flood hazard area is floodplain land subject to a one or greater percent chance of flooding in any given year (a.k.a. the 100-year flood). The area may be designated as "Zone A" on the flood hazard map. After detailed rate-making has been completed in preparation for the publication of a flood insurance rate map, Zone A usually is refined into Zones A, AO, AH, A1-30, AE, A99, AR, VO, or V1-30, VE or V.
Floodplain regulations are meant to:
Floodway: Since this area is the most dangerous part of the floodplain, activities are strictly regulated here. Certain activities and uses are allowed here provided they meet these strict criteria:
Flood-fringe: Certain activities and uses are permitted in the floodway, provided they meet certain development standards:
Conditional uses (sometimes referred to as special exceptions) may be granted by the locality upon application and public hearing provided that provisions, purpose and objectives of the floodplain-zoning ordinance are met.
The local board of zoning appeals may grant variances or appeals upon application and public hearing provided that the application can meet strict criteria. However:
To view Virginia's laws regarding floodplain management, see Code of Virginia §10.1-602. Click here for model ordinances for Virginia's communities. If you have questions, please contact the Virginia Floodplain Management Program staff: (804) 371-6135, firstname.lastname@example.org; (804) 371-6137, email@example.com.