Campaign: Earth Science

Delineating Watershed Boundaries Using The National Map

The National Elevation Dataset, the elevation layer of The National Map, is the framework for a multi-layered hydrologic database called the Elevation Derivatives for National Applications (EDNA). Using valuable flow direction characteristics within the EDNA, an elevation-derived watershed tool is available to delineate and download watershed boundaries by selecting a point anywhere within the conterminous United States. The tool was developed by the U.S. Geological Survey, Earth Resources Observation and Science Center, Topographic Science, and is available online at

Submitted by



- [ Show all ]


2 votes
Idea No. 12