The University of Connecticut and the U.S. Geological Survey (USGS) collected low-altitude (30-50 m above ground level) airborne visible-light imagery data via a quadcopter, small unoccupied aircraft system (UAS or ‘drone’) deployed along two tributary confluence locations within the Housatonic River: Mill Brook (latitude: 42°52’18” N, longitude: 73°21’48” W) and Furnace Brook (latitude: 41°49’16” N, longitude: 73°22’17” W). Both tributary confluence sites serve as critical summer thermal refuge for cold water-adapted poikilotherms. The objectives for this data collection included the creation of high-resolution orthomosaic images of the two tributary confluences to infer bank and instream structures and mixing processes at the tributary confluences. Detailed site-scale maps such as these are important tools for managers and researchers aiming to protect and conserve populations at risk. The UAS (Mavic 2 Zoom, DJI Enterprises) was flown several times per day, at wind speeds below 10 mph, capturing RGB imagery from March 24-25, 2021. The UAV flights collected single RGB JPG images at 30-50m above ground level using the double-grid flight pattern on the third-party app Pix4D Capture (https://www.pix4d.com/product/pix4dcapture). The images were stitched automatically into several orthomosaic images using Agisoft Metashape (Agisoft LLC, St. Petersburg, Russia) software as described in the ‘processed_data’ subfolders of this data release. Structure from Motion techniques were also applied to the visual imagery to derive time-specific, digital surface models (DSM) of the exposed banks and some subsurface features.

A Bell 407 helicopter with a gyro-stabilized gimbal was used to collect aerial videos of Upper Colorado River Water Science Basin (IWS) riverine study sites in 2022. Videos were collected using both natural color and thermal infrared cameras. These videos were used to determine the feasibility of estimating river surface velocity using aerial imagery. Photogrammetry techniques were used with the natural color video images to produce an orthomosaic map of the study reach.

A Bell 407 helicopter with a gyro-stabilized gimbal was used to collect aerial videos of Upper Colorado River Water Science Basin (IWS) riverine study sites in 2022. Videos were collected using both natural color and thermal infrared cameras. These videos were used to determine the feasibility of estimating river surface velocity using aerial imagery. Photogrammetry techniques were used with the natural color video images to produce an orthomosaic map of the study reach.

A Bell 407 helicopter with a gyro-stabilized gimbal was used to collect aerial videos of Integrated Water Science (IWS) basin riverine study sites in 2022. Videos were collected using both natural color and thermal infrared cameras. These videos were used to determine the feasibility of estimating river surface velocity using aerial imagery. Orthomosaic maps were produced from the natural color videos using photogrammetry techniques. Separate child pages were created to provide access to both the videos collected and the orthomosaic maps produced for each IWS basin (Delaware River, Illinois River, and Upper Colorado River).

A Bell 407 helicopter with a gyro-stabilized gimbal was used to collect aerial videos of Integrated Water Science (IWS) basin riverine study sites in 2022. Videos were collected using both natural color and thermal infrared cameras. These videos were used to determine the feasibility of estimating river surface velocity using aerial imagery. Orthomosaic maps were produced from the natural color videos using photogrammetry techniques. Separate child pages were created to provide access to both the videos collected and the orthomosaic maps produced for each IWS basin (Delaware River, Illinois River, and Upper Colorado River).

A Bell 407 helicopter with a gyro-stabilized gimbal was used to collect aerial videos of Delaware River Water Science Basin (IWS) riverine study sites in 2022. Videos were collected using both natural color and thermal infrared cameras. These videos were used to determine the feasibility of estimating river surface velocity using aerial imagery. Photogrammetry techniques were used with the natural color video images to produce an orthomosaic map of the study reach.

A Bell 407 helicopter with a gyro-stabilized gimbal was used to collect aerial videos of Delaware River Water Science Basin (IWS) riverine study sites in 2022. Videos were collected using both natural color and thermal infrared cameras. These videos were used to determine the feasibility of estimating river surface velocity using aerial imagery. Photogrammetry techniques were used with the natural color video images to produce an orthomosaic map of the study reach.

These orthophotos and digital surface model (DSM) were derived from low-altitude (approximately 92-m above ground surface) images collected from Unmanned Aerial System (UAS) flights over edge-of-field sites that are part of U.S. Geological Survey (USGS) Great Lakes Restoration Initiative (GLRI) monitoring. The objective of this UAS photogrammetry data collection was to provide information on the tile-drain network in individual fields with the goal of understanding already observed patterns in runoff amount and water quality from these sites. A 3DR Solo quadcopter served as the flight vehicle, flights were pre-planned using Mission Planner, and flights were flown using Tower. Geospatial data were originally in WGS84 and projected to a local coordinate system for each site. Visible color (Vis-C) imagery was collected with a Ricoh GRII as a single band. Images were collected at 2-second intervals, with a flight speed of 9 meters per second (m/s) and with approximately 75% overlap between sequential images and 70% sidelap between adjacent flight lines. Cameras used local time for visible and thermal imagery collection but Coordinated Universal Time (UTC) for multispectral imagery collection. Photogrammetry to integrate the individual images into an orthophoto and digital surface model (for visible imagery) was done using Agisoft Metashape.

These orthophotos and digital surface model (DSM) were derived from low-altitude (approximately 92-m above ground surface) images collected from Unmanned Aerial System (UAS) flights over edge-of-field sites that are part of U.S. Geological Survey (USGS) Great Lakes Restoration Initiative (GLRI) monitoring. The objective of this UAS photogrammetry data collection was to provide information on the tile-drain network in individual fields with the goal of understanding already observed patterns in runoff amount and water quality from these sites. A 3DR Solo quadcopter served as the flight vehicle, flights were pre-planned using Mission Planner, and flights were flown using Tower. Geospatial data were originally in WGS84 and projected to a local coordinate system for each site. Visible color (Vis-C) imagery was collected with a Ricoh GRII as a single band. Images were collected at 2-second intervals, with a flight speed of 9 meters per second (m/s) and with approximately 75% overlap between sequential images and 70% sidelap between adjacent flight lines. Cameras used local time for visible and thermal imagery collection but Coordinated Universal Time (UTC) for multispectral imagery collection. Photogrammetry to integrate the individual images into an orthophoto and digital surface model (for visible imagery) was done using Agisoft Metashape.

Aerial images in the vicinity of USGS gaging station #07094500 Arkansas River at Parkdale, Colorado were collected on March 20-22, 2018, using Unmanned Aircraft Systems (UAS, or "drones"). Data were processed using structure-from-motion analysis to generate a three- dimensional point cloud that identifies pixels from multiple images representing the same object and calculates the x, y, and z coordinates of that object/pixel. The point cloud was processed to create a digital surface model of the site. Finally, source images were stitched together based on shared pixels and orthogonally adjusted to create a high resolution (approximately 2 cm pixel size) orthoimage for the study area. The orthomosaic image captures conditions of a 500 m reach of the Arkansas River that includes the gaging station and nearby river banks, railroad, roads, and the Route 50 bridge over the river.