The Elevation Contours (1:5,000) datalayer represents contours at 3-meter intervals created from Digital Terrain Model (DTM) data points collected during the production of the 1:5,000 Black and White Digital Orthophoto images. This datalayer had previously been a mix of data from the DTMs as well as some 1:25,000 Digital Line Graph (DLG) data obtained from the U.S. Geological Society. As of August 2001 all older USGS data have been replaced by the 1:5,000 product. In April 2003 data development was completed for the entire state. The SDE layer is named CONTOURS5K_ARC.