National Wetlands Inventory
Encyclopedia
In the United States the National Wetland Inventory is a Fish and Wildlife Service program started in the 1970s to inventory and map all wetlands, primarily for scientific purposes. It has since been de-funded and most of its data is outdated. The data and maps it produces have been used to track gains and losses of wetlands for more than two decades. It uses the Cowardin Classification System to classify wetlands.