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. This dataset is the bed sediment classification derived from multibeam sonar surveys.

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. This dataset is a 1-meter resolution digital elevation model.

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. This dataset is a 1-meter resolution digital elevation model.

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 created 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. This dataset is the hillshade generated from the 1-meter resolution digital elevation model (DEM_EGC_Apr2011.tif) associated with this data release.

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 created 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. This dataset is the hillshade generated from the 1-meter resolution digital elevation model (DEM_EGC_Apr2011.tif) associated with this data release.

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 created 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. This dataset is a 1-meter resolution elevation uncertainty model generated by fuzzy inference system modeling associated from the 1-meter resolution digital elevation model (DEM_EGC_Apr2011.tif) associated with this data release.

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 created 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. This dataset is a 1-meter resolution elevation uncertainty model generated by fuzzy inference system modeling associated from the 1-meter resolution digital elevation model (DEM_EGC_Apr2011.tif) associated with this data release.

These topographic/bathymetric digital elevation models (DEMs) were collected and compiled to characterize erosion and deposition in the Colorado River and in an adjacent zone of laterally recirculating flow (eddy) during both average flow conditions and during a controlled flood that occurred in March 2008. The objectives of the study were to measure changes sandbar morphology that occurred during changes in discharge associated with the controlled flood. These data were collected between February 6 and March 31, 2008 in a 1-mile study reach on the Colorado River within Grand Canyon National Park beginning 44.5 miles downstream from Lees Ferry, Arizona. These data were collected by the USGS Grand Canyon Monitoring and Research Center with cooperators from Northern Arizona University and funding provided by the Glen Canyon Dam Adaptive Management Program. All bathymetric data were collected with a multibeam sonar system (Reson Seabat 8124 sonar with TSS MAHRSS reference system for heave, pitch, roll, and heading). Topographic data were collected by conventional total station. These data can be used to study changes in channel morphology associated with changes in streamflow conditions.

These topographic/bathymetric digital elevation models (DEMs) were collected and compiled to characterize erosion and deposition in the Colorado River and in an adjacent zone of laterally recirculating flow (eddy) during both average flow conditions and during a controlled flood that occurred in March 2008. The objectives of the study were to measure changes sandbar morphology that occurred during changes in discharge associated with the controlled flood. These data were collected between February 6 and March 31, 2008 in a 1-mile study reach on the Colorado River within Grand Canyon National Park beginning 44.5 miles downstream from Lees Ferry, Arizona. These data were collected by the USGS Grand Canyon Monitoring and Research Center with cooperators from Northern Arizona University and funding provided by the Glen Canyon Dam Adaptive Management Program. All bathymetric data were collected with a multibeam sonar system (Reson Seabat 8124 sonar with TSS MAHRSS reference system for heave, pitch, roll, and heading). Topographic data were collected by conventional total station. These data can be used to study changes in channel morphology associated with changes in streamflow conditions.