Description |
This portion of the data release presents a digital elevation model (DEM) of portions of Oxbow Reservoir in Placer County, California. The DEM was created using topographic survey data collected on 26 October 2022, when the reservoir was partially de-watered to allow repairs to the dam infrastructure following the Mosquito Fire. Although the gates of the dam were open during this time, significant portions of the reservoir site remained inaccessible to surveyors due to the continued flow of the Middle Fork American River. Consequently, this DEM covers approximately 50 percent of the total surface area of the reservoir at full pool. The raw topographic data for the DEM were collected using two RTK GNSS backpack rovers which were referenced to a temporary GNSS base station occupying a fixed control point ("CP512") located less than 1 kilometer from the survey area. Precise coordinates for the GNSS base station were derived using the National Geodetic Survey (NGS) Online Positioning User Service (OPUS). The GNSS data were used to create a triangulated irregular network (TIN), which was converted to raster DEM. The resulting DEM has a horizontal resolution of 1 meter and is formatted as a GeoTIFF. [More]
|