AbstractDiversion Structures in the NHDTrack: Water Resources Author The National Hydrography Dataset (NHD) provides a comprehensive representation of the surface water of the United States. These data largely represent the natural flow of water on the landscape using streams, rivers, and lakes. However, most of the engineered diversion features are not properly incorporated into the network. Although the typical diversion conduits of canals, ditches, pipelines, and tunnels are normally present in the NHD, an explicit identification point is needed to identify where an engineered diversion or confluence occurs. Such points also need a linear referencing address. Network analysis can then use these points to more accurately model flow. Most state water agencies have extensive diversion databases and the goal is to incorporate the pertinent structures into the NHD to assemble standardized information useful to data users. A number of issues need to be addressed to make this work useful. Jeffrey Simley U.S. Geological Survey P.O. Box 25046, MS-510, DFC Denver, Colorado 80225 United States Phone: 303-202-4131 Fax: 303-202-4020 E-mail: jdsimley@usgs.gov |