The 2002 Digital Surface Model (DSM) dataset consists of single band rasters at 1-meter pixel resolution that were generated to orthorectify a four band ortho imagery acquisition, and to support development of additional GIS products. Each pixel represents the elevation of the surface at that point expressed as NAD83 ellipsoid height. The DSM is a reflective surface DSM which provides elevation data on open ground (e.g. bare soil, rocks, and water), as well as aboveground terrain features including buildings, trees, and vegetation that cover otherwise open ground. The Digital Surface Model (DSM) was generated by automatic correlation of stereoscopic imagery collected from a flight altitude of approximately 17,000 feet above river level (approximately 18,000 to 21,000 feet above mean sea level) at 22-cm resolution with a HRSC-AX push-broom sensor May 24 through June 5, 2002. Data were collected during a period of low steady flow of approximately 8,000 cubic feet per second released from Glen Canyon Dam. The data are for the segment of the Colorado River riparian corridor from Glen Canyon Dam downstream to Pearce Ferry, AZ.

The 2013 Digital Surface Model (DSM) dataset consists of single band rasters at 1-meter pixel resolution that were generated to orthorectify a four band ortho imagery acquisition, and to support development of additional GIS products. Each pixel represents the elevation of the surface at that point expressed as NAD83 ellipsoid height. The DSM is a reflective surface DSM which provides elevation data on open ground (e.g. bare soil, rocks, and water), as well as aboveground terrain features including buildings, trees, and vegetation that cover otherwise open ground. The Digital Surface Model (DSM) was generated by automatic correlation of stereoscopic imagery collected from approximately 8,000 ft to 11,000 ft above mean sea level at 20-cm resolution with one Leica ADS80/82 digital multi-spectral sensor on each of two aircraft May 25, 2013 – May 30, 2013. Data were collected during a period of low steady river flow of approximately 8,000 cubic feet per second released from Glen Canyon Dam. The data are for the segment of the Colorado River corridor from Glen Canyon Dam downstream to Pearce Ferry, AZ.

These datasets consist of four, 1-meter spatial resolution digital surface models (DSMs) that were generated to orthorectify airborne multispectral imagery acquired in 2002, 2009, 2013, and 2021 for the Colorado River in Grand Canyon in Arizona, USA. These datasets also consist of a 1-meter spatial resolution digital elevation model (DEM) that was generated from the 2021 DSM. The DSMs and DEM were also produced to support development of additional GIS products. Elevation values are expressed as ellipsoid heights. These datasets also include accuracy assessments that were performed to show the limitations of estimating elevation from the DSMs and DEM pixels locations on the landscape. Data were acquired during periods of low steady Colorado River flow of approximately 8,000 cubic feet per second released from Glen Canyon Dam.

The 2021 Digital Elevation Model (DEM) dataset consists of single band rasters at 1-meter pixel resolution that were generated to orthorectify four band ortho imagery acquisition, and to support development of additional GIS products. Each pixel represents the elevation of the ground surface at that point expressed as NAD83(2011) ellipsoid height. A Digital Surface Model (DSM) was generated by automatic correlation of stereoscopic imagery collected from approximately 8,000 ft to 11,000 ft above mean sea level at 20-cm resolution with one Leica ADS100 digital push-broom multi-spectral sensor on each of two aircraft May 29, 2021 – June 4, 2021. The DEM was generated by removing the aboveground features from the DSM by filtering process. Data were collected during a period of low steady river flow of approximately 8,000 cubic feet per second released from Glen Canyon Dam. The data are for the segment of the Colorado River corridor from Glen Canyon Dam downstream to Pearce Ferry, AZ.

The horizontal accuracy assessment dataset consists of spatial coordinate and elevation values of “hard points” identified in each digital surface model (DSM) dataset and their spatial location data from the geodetic control network maintained by the U.S. Geological Survey (USGS), Grand Canyon Monitoring and Research Center (GCMRC). Surveyed “hard points” represent stationary natural features, such as corners of large boulders, that are visible in aerial imagery and elevation datasets and are in the geodetic control network maintained by the USGS, GCMRC. The vertical accuracy assessment dataset consists of pixel elevation values extracted from the DSM and digital elevation model (DEM) datasets for 926 “control points”. Surveyed "control points" represent survey marks and benchmarks in the geodetic control network maintained by the USGS, GCMRC. Each “hard point” and control point is denoted by a unique identifier from the Grand Canyon survey control network database maintained by the USGS, GCMRC. All point location are denoted by the distance upstream or downstream along the river channel from Lees Ferry, AZ. The temporal extent of the data is for the years 2002, 2009, 2013, and 2021, and the spatial extent is for the segment of the Colorado River riparian corridor from Glen Canyon Dam downstream to Pearce Ferry, AZ.

These data consist of rectified aerial photographs, measurements of active channel width, measurements of river and floodplain bathymetry and topography, and ancillary data. These data are specific to the corridor of the Colorado River in Canyonlands National Park between Potash, Utah and the confluence of the Green and Colorado Rivers near Spanish Bottom, Utah. The time period for these data are 1940 to 2018. The shapefile data are measurements of features of the active river channel and floodplains of the Colorado River. The raster data are aerial images and digital elevation models (DEMs) for segments of the Colorado River in Canyonlands National Park, Utah. The aerial images depict the river channel and adjacent floodplains for most of the corridor of the Colorado River in Canyonlands National Park upstream from the confluence with the Green River. The images were acquired from public sources and orthorectified and mosaiced for this study. The DEMs cover the river channel and adjacent floodplain for the Lockhart Creek segment of the Colorado River within Canyonlands National Park and include both bathymetric and topographic data. The bathymetric data were collected by the U.S. Geological Survey Grand Canyon Monitoring and Research Center with funding provided by the National Park Service. The topographic data are airborne lidar data that were collected for the state of Utah by a contractor. The lidar data are available at https://doi.org/10.5069/G9RV0KSQ.

Bathymetric, topographic, and grain-size data were collected in April 2011 along a 27-mi (43.5 – km) reach of the Colorado River in Grand Canyon National Park, Arizona. The study reach begins at river mile 61.1, about 0.6 -mi (1 –km) above the confluence of the Colorado and Little Colorado Rivers and ends at river mile 88.1 at the upstream boundary of the Bright Angel Rapid (Phantom Ranch boat beach). Channel bathymetry was mapped using multibeam and singlebeam echosounders, subaerial topography was mapped using ground-based total-stations, and bed-sediment grain-size data were collected using an underwater digital microscope system. These data were combined to produce digital elevation models, spatially variable estimates of digital elevation model uncertainty, georeferenced grain-size data, and bed-sediment distribution maps. These data were collected by the Southwest Biological Science Center, Grand Canyon Monitoring and Science Center as a component of a larger effort to monitor the status and trends of sand storage along the Colorado River in Grand Canyon National Park.

These data area classified maps of water in the Colorado River at a discharge of approximately 227 meters squared/second in Grand Canyon from Glen Canyon Dam to Pearce Ferry in Arizona. The data are derived from interpretation of multispectral high resolution airborne imagery that was acquired in May 2013. The water classification data have the same 0.2-meter ground resolution as the imagery. These data have not undergone a statistical accuracy assessment, but they are based on methods that included image interpretation to exhaustively identify water which have been shown to produce very high classification accuracies and excellent correlation between maps of total vegetation produced by independent analysts and ground truth. When developing these data from the native raster format we also considered the differences in water origin, and differentiated between water in the Colorado River mainstem as opposed to within tributary channels. Backwaters with fluid connection to the mainstem river channel were categorized as mainstem water. Backwaters completely disconnected from the mainstem were grouped with the tributary water. We created a water classification dataset from multispectral high resolution imagery. All processing steps were completed in ENVI + IDL 5.3 a product of Harris Geospatial Solutions (copyright 2017 Exelis Visual Information Solutions, Inc., a subsidiary of Harris Corporation) and ArcGIS 10.3 a product of ESRI (copyright 2017).