Elevation Derivatives for National Applications (EDNA) Seamless Three-Dimensional Hydrologic Database

Elevation Derivatives for National Applications (EDNA) is a seamless, nationwide, multi-layered three-dimensional (3D) hydrologic database derived from a version of the National Elevation Dataset. EDNAs 3D hydrologic layers are vertically consistent by their very nature, meaning that hydrologic drainage always flows from a higher elevation to a lower elevation and that reach catchment boundaries always follow the elevation drainage divide. This consistency allows for transfer of valuable information from digital elevation models onto EDNA-derived drainage lines and watersheds, including stream gradient, minimum and maximum elevation within a watershed, average watershed slope, and elevation. Derivative hydrologic data have numerous environmental and hydrologic applications. EDNA can be used simply as a shaded relief backdrop, or for nationwide hydrologic modeling. The database is valuable because drainage areas upstream or downstream from any location can be accurately traced facilitating flood analysis investigations, pollution studies, estimations of annual streamflow, and hydroelectric power generation. The EDNA database was completed from 2000-2003 as a collaborative effort between the U.S. Geological Survey (USGS) Earth Resources Observation and Science (EROS) Center, USGS Water Resources of the United States, National Oceanic and Atmospheric Administration, National Weather Service, National Severe Storms Laboratory, and the U.S. Environmental Protection Agency.