DOI: 10.5066/p13v7hbc
title: High-resolution orthoimagery and digital surface model of Cougar Reservoir, Oregon, December 2023

description: In cooperation with the U.S. Army Corps of Engineers (USACE), the U.S. Geological Survey (USGS) surveyed ground control points and coordinated aerial photograph acquisition of Cougar Reservoir, a multi-purpose reservoir in western Oregon impounded by the 158-meter ([m]; 518-foot [ft]) tall Cougar Dam. Aerial photographs were acquired by the Civil Air Patrol (CAP) in December 2023 when water levels were at 467 m (1531 ft; National Geodetic Vertical Datum of 1929 [NGVD 29]) elevation, near typical annual “low pool” or minimum pool for flood risk management operations. Photographs were acquired at a single altitude with a WaldoAir XCAM Ultra 50 camera mounted on a Cessna aircraft and captured the entire reservoir area as defined by full pool (or maximum conservation pool elevation), including the major tributary entering the reservoir, the South Fork McKenzie River. Dam operations at the 518-hectare (1280-acre) Cougar Reservoir, located about 7 kilometers upstream of the confluence of the South Fork McKenzie River and the McKenzie River, along with other hydrogeomorphic conditions, result in a diverse array of geomorphic processes and landforms within the reservoir. To document reservoir floor geomorphology, the USGS applied structure-from-motion (SfM) techniques to these aerial photographs, following the workflow outlined in Over and others (2021) and used for similar datasets (Schwid and others, 2025), and generated a three-dimensional xyz point cloud, digital surface model (DSM), and orthomosaic of Cougar Reservoir.
 
This data release includes ground control points, dataset footprints, original aerial photographs, a point cloud, a DSM, and an orthomosaic of Cougar Reservoir that were developed from imagery acquired on December 28, 2023. The point cloud has an average point density of 29 points per square meter, the DSM resolution is 18.6 centimeters per pixel, and the orthomosaic ground resolution is 9.28 centimeters per pixel. The DSM and orthomosaic are formatted as Cloud Optimized GeoTIFFs (COGs) for enhanced web visualization (GDAL, 2024).
 
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