Overdevelopment of shores and wetlands, dwindling sites on land for the disposal of human-generated waste, contamination of estuaries and nearshore sediments, the disruption of coastal-water ecosystems by dredging, and the specter of rising sea level due to anthropogenically induced global warming are but a few of the pressures humans are exerting on coastal environments around the world. In the United States, a lot is riding on the response of its coastal environments to these pressures. The majority of the U.S. population resides in the coastal states, where the country's largest cities and most popular recreation areas are located.

If the United States is to sustain the health and beauty of its coastal environments, then they must be managed, not only on the federal scale, but also on the state and local scales. One of the most fundamental types of data required to conduct this management will be detailed elevation data. On land, topography dictates the flow of water and the maximum extent of flooding. Offshore, bathymetry is a major control on shallow-water ocean currents and the dissemination of sediments eroded from the continent.