Summary

Description

The dataset encompasses portions of Northern Oregon, Eastern Washington, Northern Idaho, and Northwestern Montana within the Columbia River drainage. The bare earth digital elevation models (DEM) represent the earth's surface with all vegetation and human-made structures removed. The bare earth DEMs were derived from LiDAR data using TIN processing of the ground point returns. The DEM grid cell size is 1 m. The elevation units are in meters. Some elevation values have been interpolated across areas in the ground model where there is no elevation data (e.g. over dense vegetation). Breaklines derived from lidargrammetry were used to enforce water boundaries and interpolate some areas where the ground was obscured from the LiDAR data. Water surfaces were derived from a TIN of the 3-D water edge breaklines. Watershed Sciences, Inc. collected the LiDAR and created this data set for David C. Smith & Associates, Inc. and the U.S. Army Corps of Engineers