This dataset provides a modified version of the previously published Lake Powell topobathymetric digital elevation model (TBDEM; Poppenga and others, 2020). The original TBDEM is comprised of four source datasets: (1) a 2017 1-meter multibeam bathymetric survey; (2) a 2018 topographic light detection and ranging (lidar) derived digital elevation model (DEM); (3) a historical topographic DEM that was interpolated from contours maps created in 1947 and 1959; and (4) interpolated topography where gaps existed in the bathymetric and lidar data or where historical data were not suitable (Poppenga and others, 2020). For this data release, two corrections were made to the TBDEM to address errors associated with the historic DEM and interpolated topography across data gaps: (1) filled in selected gaps of the TBDEM dataset that were corrected with the historic DEM but have since been filled with sediment; and (2) spliced alternate topographic data sources instead of the hydro-flattened elevations in the river channel upstream of the Colorado and San Juan River deltas. The modified TBDEM was generated in a horizontal projection of UTM Zone 12N, North American Datum of 1983, referenced to the North American Vertical Datum 1988 (NAVD88), Geoid 12b at a 1-meter horizontal resolution. The modified TBDEM and an updated spatial metadata shapefile detailing data sources used and modifications made to the TBDEM are included with this release.

To support the modeling of the Colorado River water storage area capacity tables by the U.S. Geological Survey (USGS) Utah Water Science Center in the Glen Canyon National Recreation Area in Utah and Arizona, the USGS Earth Resources Observation and Science (EROS) Center has created an integrated 1-meter topobathymetric digital elevation model (TBDEM) for Lake Powell, the second largest man-made reservoir in the United States. Located in south-central Utah and north-central Arizona, Lake Powell is a reservoir on the Colorado River created by the flooding of a natural canyon by the construction of Glen Canyon Dam. The new Lake Powell TBDEM consists of the best available multi-source topographic and bathymetric elevation data for Lake Powell onshore and offshore areas. The Lake Powell TBDEM integrates three different data sources including topographic light detection and ranging (lidar) point cloud data, multibeam bathymetric surveys, and historic topographic surveys obtained from the Department of the Interior (DOI) Bureau of Reclamation (BOR) and USGS Woods Hole Coastal Marine Science Center. The topographic, bathymetric, and historic topographic surveys were sorted and prioritized based on survey date, accuracy, spatial distribution, and point density to develop a TBDEM model based on the best available elevation data. The Lake Powell TBDEM spatial resolution is 1-meter with the general location ranging from Glen Canyon Dam northwest of Page, Arizona to White Canyon, Utah with elevations from 948.28 meters to 1440.94 meters referenced to North American Vertical Datum of 1988 (NAVD88), National Geodetic Survey Geoid 12B. The topographic lidar survey was acquired from 4/2/18 to 4/3/18. The bathymetry survey was acquired from 10/8/17 to 11/15/17. The historic topographic surveys ranged from 1947-1959. Some of the nearshore void zone (not covered by lidar or multibeam) was filled with historic topographic surveys digitized from historical maps from 1947-1959 and a kriging interpolation as published by the USGS Coastal National Elevation Database (CoNED) Applications Project at https://doi.org/10.2112/SI76-008. Additional information regarding the CoNED Applications Project is located at https://www.usgs.gov/land-resources/eros/coned.

To support the modeling of the Colorado River water storage area capacity tables by the U.S. Geological Survey (USGS) Utah Water Science Center in the Glen Canyon National Recreation Area in Utah and Arizona, the USGS Earth Resources Observation and Science (EROS) Center has created an integrated 1-meter topobathymetric digital elevation model (TBDEM) for Lake Powell, the second largest man-made reservoir in the United States. Located in south-central Utah and north-central Arizona, Lake Powell is a reservoir on the Colorado River created by the flooding of a natural canyon by the construction of Glen Canyon Dam. The new Lake Powell TBDEM consists of the best available multi-source topographic and bathymetric elevation data for Lake Powell onshore and offshore areas. The Lake Powell TBDEM integrates three different data sources including topographic light detection and ranging (lidar) point cloud data, multibeam bathymetric surveys, and historic topographic surveys obtained from the Department of the Interior (DOI) Bureau of Reclamation (BOR) and USGS Woods Hole Coastal Marine Science Center. The topographic, bathymetric, and historic topographic surveys were sorted and prioritized based on survey date, accuracy, spatial distribution, and point density to develop a TBDEM model based on the best available elevation data. The Lake Powell TBDEM spatial resolution is 1-meter with the general location ranging from Glen Canyon Dam northwest of Page, Arizona to White Canyon, Utah with elevations from 948.28 meters to 1440.94 meters referenced to North American Vertical Datum of 1988 (NAVD88), National Geodetic Survey Geoid 12B. The topographic lidar survey was acquired from 4/2/18 to 4/3/18. The bathymetry survey was acquired from 10/8/17 to 11/15/17. The historic topographic surveys ranged from 1947-1959. Some of the nearshore void zone (not covered by lidar or multibeam) was filled with historic topographic surveys digitized from historical maps from 1947-1959 and a kriging interpolation as published by the USGS Coastal National Elevation Database (CoNED) Applications Project at https://doi.org/10.2112/SI76-008. Additional information regarding the CoNED Applications Project is located at https://www.usgs.gov/land-resources/eros/coned.

The U.S. Geological Survey (USGS) collected hydroacoustic data of the St. Croix River adjacent to the Osceola (WI) boat ramp for hydrographic and benthic mapping prior to the reconstruction project implemented by the National Park Service (NPS). High-resolution bathymetry data was surveyed using a multibeam sonar. The depth and characteristics of the riverbed are important parameters of habitat for benthic (bottom-dwelling) organisms, and are a fundamental parameter for riverine ecosystems. A terrestrial lidar unit was used to collect shoreline elevation points. These datasets were highly desired by the NPS to help inform and mitigate potential impacts to mussels or benthic habitat.

The U.S. Geological Survey (USGS) collected hydroacoustic data of the St. Croix River adjacent to the Osceola (WI) boat ramp for hydrographic and benthic mapping prior to the reconstruction project implemented by the National Park Service (NPS). High-resolution bathymetry data was surveyed using a multibeam sonar. The depth and characteristics of the riverbed are important parameters of habitat for benthic (bottom-dwelling) organisms, and are a fundamental parameter for riverine ecosystems. Contours are an outline or boundary of specified depth intervals. These datasets were desired by the NPS to help inform and mitigate potential impacts to mussels or benthic habitat.

The U.S. Geological Survey (USGS) collected hydroacoustic data of the St. Croix River adjacent to the Osceola (WI) boat ramp for hydrographic and benthic mapping prior to the reconstruction project implemented by the National Park Service (NPS). High-resolution bathymetry data was surveyed using a multibeam sonar. The depth and characteristics of the riverbed are important parameters of habitat for benthic (bottom-dwelling) organisms, and are a fundamental parameter for riverine ecosystems. Contours are an outline or boundary of specified depth intervals. These datasets were desired by the NPS to help inform and mitigate potential impacts to mussels or benthic habitat.