sir2016-5029_Low_Res_Extents: Flood-Inundation Maps for the Coast Fork Willamette River from Creswell, Oregon to Goshen, Oregon

The Digital Elevation Model (DEM) utilized for this Willamette FIS submittal was produced by combining multiple overlapping topographic surveys for the Middle Fork and Coast Fork of the Willamette River. The DEM was created from four sources: LIDAR of the Springfield area that was flown in 2008, LIDAR of Silk Creek that was flown in 2011, LIDAR of Fall Creek that was flown in 2012, and photogrammetry of the Middle Fork and Coast Fork of the Willamette River that was flown in 2004. In areas where no high-resolution elevation data were available, USGS National Elevation Dataset (NED) data were used to supplement the DEM. This feature represents the areas NED information is presented. The horizontal datum of the DEM is NAD 1983 State [...]

本次用于威拉米特流域FIS提交的数字高程模型（Digital Elevation Model, DEM），通过合并威拉米特河中游支流与海岸支流的多份重叠地形测量数据制作而成。该DEM的数据源共四类：2008年航测获取的斯普林菲尔德地区激光雷达（LIDAR）数据、2011年航测获取的锡尔克里克激光雷达（LIDAR）数据、2012年航测获取的福尔克里克激光雷达（LIDAR）数据，以及2004年航测获取的威拉米特河中游支流与海岸支流摄影测量数据。在暂无高分辨率高程数据的区域，采用美国地质调查局（USGS）国家高程数据集（National Elevation Dataset, NED）对该DEM进行补充。本要素图层即代表应用了NED数据的区域。该DEM的水平基准面为NAD 1983 State[...]