As the glacial ice melted, sea levels which had dropped about 300 feet below present levels, was raised rapidly for the first several thousand years. As sea level rose, so did the water table, and wetlands formed along flooded stream valleys, gradually extending inland to the present western margin of the swamp. Sea level reached its present elevation about 3,000 years ago, and by that time peat was developing throughout the entire wetlands area. Trees making up the forests gradually changed, as the climate warmed, from northern species, including jack pines and spruces, to the present day cypress-gum associations. The forest groups of today have been fairly stable for the past 3,500 years.
Wetlands come in all sizes and shapes.
They may be found in prairies, at high elevations in mountainous areas, in hill country, and especially in deltas and coastal lowlands. The areas of immediate concern is a parcel of the Great Dismal Swamp, a coastal plain fresh water wetlands in northern Currituck County. It is difficult to define wetlands, because there is so much variety. However, they are all generally low compared to the surrounding area. They are often waterlogged or covered by shallow water for all or part of a year, and they support plant and animal communities which have adapted to water budgets with marked seasonal variations.