The USA national maps included here feature environmental quality information collected by EPA and other federal, state, and local agencies. LAND Links to maps of landscape and land use features. A national map is a summary of data collected across the United States. Many of our national maps are of the conterminous U.S. only, meaning the lower 48 states. Where information is available, the maps also include Alaska, Hawaii, and the Territories.
National maps summarize the environment.
Not every feature or data point that contributes to mapped results can be shown on a map of the entire United States. To make summary maps, data points from an area are grouped together and analyzed as a collection rather than individually. In these national maps, areas for this analysis are generally defined by county, by distance, or by watershed.