Abstract
Referencing and Analyzing Dams with the National Hydrography Dataset Track: Water Resources Author(s): Jeff Simley, Bill Smith Dams are highly significant features in the analysis of a stream network. Fortunately, two GIS databases can be brought together to make the analysis of dams a feasible and efficient process. The National Hydrography Dataset (NHD) provides a database of the nation's surface water that includes flow modeling and linear addressing capabilities. The National Inventory of Dams (NID) provides a database of dam locations and characteristics. By snapping and addressing these dams to the NHD, the dams can be located on the appropriate flow path, greatly enhancing their value to GIS analysis by allowing their detection in upstream or downstream searches. Using linear addresses with the NHD logical flow table, it is possible to create sophisticated queries to search and analyze highly unique scenarios. Experiences learned in indexing the NID demonstrate the capabilities and limitations possible with this dataset. Examples of query techniques also demonstrate the level of sophistication that can be achieved. Jeff Simley U.S. Geological Survey Geography PO Box 25046, MS-507, DFC Denver , CO 80225 US Phone: 303-202-4131 E-mail: jdsimley@usgs.gov Bill Smith U.S. Geological Survey Geographic Information Office P.O Box 25046, MS-507 Denver Federal Center Denver , CO 80225 US Phone: 303-202-4493 E-mail: wjsmith@usgs.gov |
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