This dataset includes the input (raw survey data, computational mesh, hydrologic boundary conditions) and output data for a 2-dimensional hydraulic and sediment transport model of the lower Snow River flood plain near Seward, Alaska. Four outburst flood scenarios were simulated, including 3 historical floods and one hypothetical larger flood. The methods of deriving these datasets and using them to calculate scour are described in the associated USGS Scientific Investigations Report "Recent history of glacial outburst floods, analysis of channel changes, and development of a 2-dimensional flow and sediment transport model of the Snow River near Seward, Alaska".

This data release includes 3 child items with mapping, measurement, and modeling of glacial outburst floods on the Snow River near Seward, Alaska. Child Item 1: "Historical Channel Positions and Alluvial Fan Extents for the Lower 10 Kilometers of the Snow River Flood Plain Near Seward, Alaska" Child Item 2: "Height Above River Elevations for the Lower 10 Kilometers of the Snow River Flood Plain Near Seward, Alaska" Child Item 3: "Tabular Input/Output Data and Model Files for a Two-dimensional Hydraulic and Sediment Transport Model of the Lower 10 Kilometers of the Snow River Near Seward, Alaska"

A height-above-river raster produced from 2008 lidar bare-earth elevations for the lower 10 kilometers of the Snow River flood plain is used as part of a geomorphic assessment to identify areas susceptible to inundation and erosion during outburst floods from Snow Lake. This dataset presents flood plain elevations above the approximate elevation of the main river channel low water surface.

A height-above-river raster produced from 2008 lidar bare-earth elevations for the lower 10 kilometers of the Snow River flood plain is used as part of a geomorphic assessment to identify areas susceptible to inundation and erosion during outburst floods from Snow Lake. This dataset presents flood plain elevations above the approximate elevation of the main river channel low water surface.

This data release includes tabular surveyed and interpolated elevation data, the processed computational mesh, and model output data used in streambed scour evaluations at selected bridge sites in Alaska, 2016-2017. This is a cooperative project with Alaska Department of Transportation and Public Facilities. The methods of deriving these datasets and using them to calculate scour are described in the associated U.S. Geological Survey Scientific Investigations Report https://doi.org/10.3133/sir20195110.

This data release includes tabular surveyed and interpolated elevation data, the processed computational mesh, and model output data used in scour evaluations. The methods of deriving these datasets and using them to calculate scour are described in the associated Scientific Investigations Report "Scour evaluations and conditions at selected bridge sites in Alaska, 2016-2017”. This is a cooperative project with Alaska Department of Transportation and Public Facilities.

The USGS mapped main channels and alluvial fan extents in the lower 10 kilometers of the Snow River flood plain near Seward, Alaska as part of an assessment of river channel stability under an outburst flood regime. Channels and fan extents were mapped from aerial photographs and satellite imagery dating from 1951 to 2019.

The USGS mapped main channels and alluvial fan extents in the lower 10 kilometers of the Snow River flood plain near Seward, Alaska as part of an assessment of river channel stability under an outburst flood regime. Channels and fan extents were mapped from aerial photographs and satellite imagery dating from 1951 to 2019.

The Geospatial Fabric for National Hydrologic Modeling (Viger and Bock, 2014; Bock and others, 2020) is a dataset of hydrographic features and spatial data designed for use within the National Hydrologic Model that covers the conterminous United States (CONUS), Hawaii, and most major river basins that flow in from Canada. This U.S. Geological Survey (USGS) data release consists of the geospatial fabric features and other related spatial datasets created to expand the National Hydrologic Model to Alaska. This child item consists of topographic data themes that cover the Geospatial Fabric for National Hydrologic Modeling, Alaska Domain. The 30-meter (m) raster datasets included under Topographic Derivatives are: digital elevation (dem.tif), topographic wetness index (TWI, twiX100.tif), slope (rise over run, slope.tif), aspect (asp.tif), flow accumulation (fac.tif), and flow direction (fdr.tif). All file formats are in GeoTIFF (Geographic Tagged Imaged Format), and are sourced from NHDPlus Version 2.0 raster layers (Environmental Protection Agency, 2019)

The Geospatial Fabric for National Hydrologic Modeling (Viger and Bock, 2014; Bock and others, 2020) is a dataset of hydrographic features and spatial data designed for use within the National Hydrologic Model that covers the conterminous United States (CONUS), Hawaii, and most major river basins that flow in from Canada. This U.S. Geological Survey (USGS) data release consists of the geospatial fabric features and other related spatial datasets created to expand the National Hydrologic Model to Alaska. This child item consists of topographic data themes that cover the Geospatial Fabric for National Hydrologic Modeling, Alaska Domain. The 30-meter (m) raster datasets included under Topographic Derivatives are: digital elevation (dem.tif), topographic wetness index (TWI, twiX100.tif), slope (rise over run, slope.tif), aspect (asp.tif), flow accumulation (fac.tif), and flow direction (fdr.tif). All file formats are in GeoTIFF (Geographic Tagged Imaged Format), and are sourced from NHDPlus Version 2.0 raster layers (Environmental Protection Agency, 2019)