Topobathymetric Digital Elevation Model (TBDEM) for Coastal Oregon and Washington including Columbia River Corridor, 1851 - 2025

To support U.S. Geological Survey (USGS) Pacific Coastal and Marine Science Center (PCMSC) flood inundation and hydrodynamic modeling, the USGS Coastal National Elevation Database (CoNED) Applications Project has created an integrated 1-meter topobathymetric digital elevation model (TBDEM) for coastal Oregon and Washington, including the tidal portions of the Columbia River. Coastal topobathymetry data are required to characterize flooding, storms, and sea-level-rise inundation hazard zones, as well as other earth science applications, such as the development of storm-surge and sediment-transport models. This TBDEM consists of the best available multi-source topographic and bathymetric elevation data for coastal Oregon and Washington, including neighboring bays, estuaries, inlets, islands, and the Columbia River. The coastal Oregon and Washington TBDEM integrates 132 different data sources, including topographic and bathymetric data, such as lidar point clouds and multi-beam acoustic surveys obtained from USGS, the National Oceanic and Atmospheric Administration (NOAA), the U.S. Army Corps of Engineers, Oregon Department of Geology and Mineral Industries (DOGAMI), United States Forest Service (USFS), and Puget Sound LiDAR Consortium (PSLC)[JD1.1]. The topographic and bathymetric surveys were sorted and prioritized by survey date, accuracy, spatial distribution, and point density to develop a model using the best available elevation and bathymetric data. Disparate geospatial sources were spatially integrated using enhanced blending techniques to ensure continuous, seamless transitions between high- and coarse-resolution data sources and across the littoral zone/riverine interfaces. Because bathymetric data are referenced to tidal datums, such as Mean High Water or Mean Lower Low Water, all tidally referenced heights were transformed into orthometric heights using the GEOID18 geoid, which is typically used for mapping elevation on land with the North American Vertical Datum of 1988 (NAVD88). The spatial horizontal resolution is 1-meter referenced to UTM Zone 10N, NAD83 (2011), with the general location ranging from the California/Oregon border in the south to past Grays Harbor on the Washington Coast, extending inland to include the tidal reach of the Columbia River along with offshore depths. Vertically, the TBDEM is referenced to NAVD88/GEOID18. The overall temporal range of the input topography and bathymetry is from 1851 to 2025, with depths reaching approximately 1,300 meters. The topography surveys are from 2007 to 2022. Bathymetry surveys were acquired between 1851 and 2025 [JD2.1]. This data release was funded by the USGS Coastal and Marine Hazards and Resources Program (CMHRP). This TBDEM is a publicly available USGS product and is distributed as 17 100-kilometer by 100-kilometer tiles in cloud-optimized GeoTIFF (COG) format. A continuous mosaic is provided as a virtual raster (VRT) that references and streams the individual COG-formatted GeoTIFFs.