Carl J Legleiter
(He/him)Carl joined the U.S. Geological Survey in 2016 and has a Ph.D. in Geography from the University of California Santa Barbara.
As a member of the USGS Water Resources Mission Area Hydrologic Remote Sensing Branch, Carl conducts research on remote sensing of rivers, specifically retrieval of depth, velocity, and other channel attributes from various types of image data. Current efforts are focused on the development and testing of methods for estimating surface flow velocities from videos and image time series acquired from Uncrewed Aircraft Systems (UAS, or drones), helicopters, and moving aircraft. In addition, he is actively involved in ongoing studies seeking to advance our ability to characterize potentially harmful algal blooms (HABs) via hyperspectral imaging. Another topic of continued interest is a collaborative project with the USGS Ecosystems Mission Area to assess habitat for pallid sturgeon on the Missouri River by conducting tracer experiments. This study involves estimating concentrations of the tracer dye from remotely sensed data to better understand dispersion processes operating within the river.
Professional Experience
2016-present: Research Hydrologist, USGS Water Resources Mission Area, Hydrologic Remote Sensing Branch
2015-2016: Associate Professor, Geography, University of Wyoming
2009-2015: Assistant Professor, Geography, University of Wyoming
2009-2015: Faculty Affiliate and volunteer, USGS Geomorphology & Sediment Transport Laboratory
2009: Hydrologist, USGS Geomorphology & Sediment Transport Laboratory
2004-2006: Graduate Student Assistant, San Joaquin District River Management Section, California Department of Water Resources
Education and Certifications
B.S. – Earth Sciences, Montana State University, Bozeman, Montana (2002)
B.S. – Mathematical Sciences, Montana State University, Bozeman, Montana (2002)
M.A. – Geography, UC Santa Barbara, Santa Barbara, California (2004)
Ph.D. – Geography, UC Santa Barbara, Santa Barbara, California (2008)
Science and Products
Filter Total Items: 43
Field measurements of water depth from the Colorado River near Lees Ferry, AZ, March 16-18, 2021
Field measurements of water depth were acquired from a reach of the Colorado River near Lees Ferry, Arizona, March16-18, 2021, to support research on remote sensing of water depth from satellite images. The depth measurements included in this data release were obtained along a series of cross-sections using a SonTek RiverSurveyor M9 acoustic Doppler current profiler (ADCP) deployed from a boat. Th
Field measurements of water depth from the American River near Fair Oaks, CA, October 19-21, 2020
Field measurements of water depth were acquired from a reach of the American River at Sailor Bar, near Fair Oaks, California, October 19-21, 2020, to support research on remote sensing of water depth from satellite images. The depth measurements included in this data release were obtained via two different methods: 1) By wading the shallow channel margins with RTK GPS receivers and measuring water
Phytoplankton identification and biovolume data for field samples from Detroit Lake, Oregon, and Owasco Lake, New York, collected in August 2019 and August 2020
This dataset contains taxonomic and biovolume data for phytoplankton sampled from Detroit Lake, OR, in August, 2019, and August, 2020. Taxonomy is reported to the lowest possible taxonomic level along with total and percent biovolume. Surface grab samples for phytoplankton enumeration were collected with a van Dorn type sampler and then transferred into a clearn polycarbonate churn. Whole water sa
Helicopter-based videos and field measurements of flow depth and velocity from the Tanana River, Alaska, acquired on July 24, 2019
This data release includes videos acquired from a helicopter and field measurements of flow depth and velocity from the Tanana River near Nenana, Alaska, obtained on July 24, 2019. This parent data release includes links to child pages for two data sets produced during the study: 1. Acoustic Doppler Current Profiler (ADCP) field measurements of flow depth and velocity from the Tanana River, Alas
Topographic, temperature, and sediment grain size data used to evaluate potential habitat for anadromous salmonids on the upper Merced and Tuolumne Rivers in California
This data release includes various data sets used to quantify the capacity of two rivers, the Merced and Tuolumne, in the Sierra Nevada of California for reintroduction of two species of anadromous salmonids, Steelhead and spring-run Chinook Salmon. The child pages linked below provide access to the following data sets: Topo-bathymetric digital elevation models of the river channels and adjacent
Satellite video and field measurements of flow velocity acquired from the Tanana River in Alaska and used for particle image velocimetry (PIV)
This data release includes a video acquired from a satellite and field measurements of flow velocity from the Tanana River in Alaska that were used to derive remotely sensed estimates of surface flow velocities via particle image velocimetry (PIV). The field data were collected on July 24, 2019, in cooperation with the USGS Alaska Science Center, and the satellite video was obtained on July 14, 2
Geo-referenced orthophotographs of the Snow River, Alaska, acquired September 1, 2018
This data release consists of orthophotographs of the Snow River in Alaska acquired on September 1, 2018. The orthophotographs were produced from images obtained using a Hasselblad A6D-100C 100 megapixel digital mapping camera deployed within a pod mounted on the landing gear of a Robinson R44 helicopter. Images were acquired as the helicopter transited a series of flight lines designed to provid
Field measurements of flow depth and optical image sequences acquired from the Salcha River, Alaska, on July 25, 2019
This data release includes field measurements of flow depth and optical image sequences acquired from the Salcha River in Alaska on July 25, 2019. These data were used to develop and test a spectrally based remote sensing technique for estimating water depth from passive optical image data. The purpose of this study was to assess the feasibility of inferring water depths from optical image seque
UAS-based remotely sensed bathymetry and field measurements from the Colorado River, near Parshall Colorado, June 13, 2019
To support an investigation of the feasibility of measuring river bathymetry using remotely sensed data acquired from a small unmanned aircraft system (sUAS), remotely sensed bathymetry and field measurements were collected from two cross-sections on the Colorado River near Parshall, CO on June 13, 2019. This parent data release includes links to child pages for the following data sets: 1) Lidar
UAS-based remotely sensed data and field measurements from the Blue River and Colorado River, near Kremmling, Colorado, October 17-18, 2018
To support an investigation of the feasibility of measuring river bathymetry using remotely sensed data acquired from an unmanned aircraft system (UAS), several types of remotely sensed data and field measurements were collected from two cross-sections on the Blue River and two cross-sections on the Colorado River near Kremmling, Colorado, on October 17-18, 2018. This parent data release includes
Image data and field measurements used to map salmon spawning locations via remote sensing, American River, California, November 5-7, 2018
This data release includes images and field measurements used to map chinook salmon spawning locations along the American River near Sacramento, California, via remote sensing; the data were collected November 5-7, 2018. The purpose of this study was to develop and test a spectrally based technique for identifying salmon spawning locations, known as redds, from various types of remotely sensed da
Aerial photographs from the Yampa and Little Snake Rivers in northwest Colorado used to characterize channel changes occurring between 1954 and 1961
Aerial photographs of the Yampa and Little Snake Rivers acquired in 1954 and 1961 were used to examine channel changes occurring along these two rivers during this time period. In addition, these data were used to develop and test a generalizable new approach to characterizing the uncertainty associated with analyses of channel change based on time series of remotely sensed data, which we term th
Filter Total Items: 42
Capacity of two Sierra Nevada rivers for reintroduction of anadromous salmonids: Insights from a high-resolution view
Historically, anadromous steelhead Oncorhynchus mykiss and spring-run Chinook Salmon O. tshawytscha used high-elevation rivers in the Sierra Nevada of California but were extirpated in the 20th century by construction of impassable dams. Plans to reintroduce the fish by opening migratory passage across the dams and reservoirs can only succeed if upstream habitats have the capacity to support viabl
Authors
David A. Boughton, Lee R. Harrison, Sara N. John, Rosealea M. Bond, Colin L. Nicol, Carl J. Legleiter, Ryan T. Richardson
Depths inferred from velocities estimated by remote sensing: A flow resistance equation-based approach to mapping multiple river attributes at the reach scale
Remote sensing of flow conditions in stream channels could facilitate hydrologic data collection, particularly in large, inaccessible rivers. Previous research has demonstrated the potential to estimate flow velocities in sediment-laden rivers via particle image velocimetry (PIV). In this study, we introduce a new framework for also obtaining bathymetric information: Depths Inferred from Velocitie
Authors
Carl J. Legleiter, Paul J. Kinzel
Surface flow velocities from space: Particle image velocimetry of satellite video of a large, sediment-laden river
Conventional, field-based streamflow monitoring in remote, inaccessible locations such as Alaska poses logistical challenges. Safety concerns, financial considerations, and a desire to expand water-observing networks make remote sensing an appealing alternative means of collecting hydrologic data. In an ongoing effort to develop non-contact methods for measuring river discharge, we evaluated the p
Authors
Carl J. Legleiter, Paul J. Kinzel
Improving remotely sensed river bathymetry by image-averaging
Basic data on river bathymetry is critical for numerous applications in river research and management and is increasingly obtained via remote sensing, but the noisy, pixelated appearance of image‐derived depth maps can compromise subsequent analyses. We hypothesized that this noise originates from reflectance from an irregular water surface and introduced a framework for mitigating these effects b
Authors
Carl J. Legleiter, Paul J. Kinzel
The optical river bathymetry toolkit
Spatially distributed information on water depth is essential for many applications in river research and management and, under certain circumstances, can be inferred from remotely sensed data. Although fluvial remote sensing has emerged as a rapidly developing subdiscipline of the riverine sciences, more widespread adoption of these techniques has been hindered by a lack of accessible software. T
Authors
Carl J. Legleiter
Field evaluation of a compact, polarizing topo‐bathymetric lidar across a range of river conditions
This paper summarizes field trials to evaluate the performance of a prototype compact topo‐bathymetric lidar sensor for surveying rivers. The sensor uses a novel polarization technique to distinguish between laser returns from the water surface and streambed and its size and weight permit deployment from a small unmanned aerial system (sUAS) or a boat. Field testing was designed to identify the ra
Authors
Paul J. Kinzel, Carl J. Legleiter, Paul Grams
Assessing the potential for spectrally based remote sensing of salmon spawning locations
Remote sensing tools are increasingly used for quantitative mapping of fluvial habitats, yet few techniques exist for continuous sampling of aquatic organisms, such as spawning salmonids. This study assessed the potential for spectrally based remote sensing of salmon spawning locations (i.e., redds) using data acquired from unmanned aircraft systems (UAS) along a large, gravel‐bed river. We develo
Authors
Lee R. Harrison, Carl J. Legleiter, Brandon T. Overstreet, Tomoko Bell, John Hannon
Measuring channel planform change from image time series: A generalizable, spatially distributed, probabilistic method for quantifying uncertainty
Channels change in response to natural or anthropogenic fluctuations in streamflow and/or sediment supply and measurements of channel change are critical to many river management applications. Whereas repeated field surveys are costly and time‐consuming, remote sensing can be used to detect channel change at multiple temporal and spatial scales. Repeat images have been widely used to measure long‐
Authors
Christina Leonard, Carl J. Legleiter, Devin M. Lea, John C. Schmidt
Inferring surface flow velocities in sediment-laden Alaskan rivers from optical image sequences acquired from a helicopter
The remote, inaccessible location of many rivers in Alaska creates a compelling need for remote sensing approaches to streamflow monitoring. Motivated by this objective, we evaluated the potential to infer flow velocities from optical image sequences acquired from a helicopter deployed above two large, sediment-laden rivers. Rather than artificial seeding, we used an ensemble correlation particle
Authors
Carl J. Legleiter, Paul J. Kinzel
An experimental evaluation of the feasibility of inferring concentrations of a visible tracer dye from remotely sensed data in turbid rivers
The movement of contaminants and biota within river channels is influenced by the flow field via various processes of dispersion. Understanding and modeling of these processes thus can facilitate applications ranging from the prediction of travel times for spills of toxic materials to the simulation of larval drift for endangered species of fish. A common means of examining dispersion in rivers i
Authors
Carl J. Legleiter, Paul Manley, Susannah O. Erwin, Edward A. Bulliner
Remote sensing of tracer dye concentrations to support dispersion studies in river channels
In river channels the flow field influences the dispersion of biota, contaminants, and other suspended or dissolved materials. Insight on patterns and rates of dispersion can be gained by injecting a pulse of visible dye and observing spatial and temporal variations in dye concentration as the pulse moves downstream. We evaluated the potential of passive optical remote sensing to enhance such trac
Authors
Carl J. Legleiter, Richard R. McDonald, Jonathan M. Nelson, Paul J. Kinzel, Ryan L. Perroy, Donghae Baek, Il Won Seo
Physical controls on salmon redd site selection in restored reaches of a regulated, gravel-bed river
Large‐scale river restoration programs have emerged recently as a tool for improving spawning habitat for native salmonids in highly altered river ecosystems. Few studies have quantified the extent to which restored habitat is utilized by salmonids, which habitat features influence redd site selection, or the persistence of restored habitat over time. We investigated fall‐run Chinook salmon spawni
Authors
Lee R. Harrison, Erin Bray, Brandon T. Overstreet, Carl J. Legleiter, Rocko A. Brown, Joseph E. Merz, Roselea M. Bond, Colin L Nicol, Thomas Dunne
Science and Products
- Data
Filter Total Items: 43
Field measurements of water depth from the Colorado River near Lees Ferry, AZ, March 16-18, 2021
Field measurements of water depth were acquired from a reach of the Colorado River near Lees Ferry, Arizona, March16-18, 2021, to support research on remote sensing of water depth from satellite images. The depth measurements included in this data release were obtained along a series of cross-sections using a SonTek RiverSurveyor M9 acoustic Doppler current profiler (ADCP) deployed from a boat. ThField measurements of water depth from the American River near Fair Oaks, CA, October 19-21, 2020
Field measurements of water depth were acquired from a reach of the American River at Sailor Bar, near Fair Oaks, California, October 19-21, 2020, to support research on remote sensing of water depth from satellite images. The depth measurements included in this data release were obtained via two different methods: 1) By wading the shallow channel margins with RTK GPS receivers and measuring waterPhytoplankton identification and biovolume data for field samples from Detroit Lake, Oregon, and Owasco Lake, New York, collected in August 2019 and August 2020
This dataset contains taxonomic and biovolume data for phytoplankton sampled from Detroit Lake, OR, in August, 2019, and August, 2020. Taxonomy is reported to the lowest possible taxonomic level along with total and percent biovolume. Surface grab samples for phytoplankton enumeration were collected with a van Dorn type sampler and then transferred into a clearn polycarbonate churn. Whole water saHelicopter-based videos and field measurements of flow depth and velocity from the Tanana River, Alaska, acquired on July 24, 2019
This data release includes videos acquired from a helicopter and field measurements of flow depth and velocity from the Tanana River near Nenana, Alaska, obtained on July 24, 2019. This parent data release includes links to child pages for two data sets produced during the study: 1. Acoustic Doppler Current Profiler (ADCP) field measurements of flow depth and velocity from the Tanana River, AlasTopographic, temperature, and sediment grain size data used to evaluate potential habitat for anadromous salmonids on the upper Merced and Tuolumne Rivers in California
This data release includes various data sets used to quantify the capacity of two rivers, the Merced and Tuolumne, in the Sierra Nevada of California for reintroduction of two species of anadromous salmonids, Steelhead and spring-run Chinook Salmon. The child pages linked below provide access to the following data sets: Topo-bathymetric digital elevation models of the river channels and adjacentSatellite video and field measurements of flow velocity acquired from the Tanana River in Alaska and used for particle image velocimetry (PIV)
This data release includes a video acquired from a satellite and field measurements of flow velocity from the Tanana River in Alaska that were used to derive remotely sensed estimates of surface flow velocities via particle image velocimetry (PIV). The field data were collected on July 24, 2019, in cooperation with the USGS Alaska Science Center, and the satellite video was obtained on July 14, 2Geo-referenced orthophotographs of the Snow River, Alaska, acquired September 1, 2018
This data release consists of orthophotographs of the Snow River in Alaska acquired on September 1, 2018. The orthophotographs were produced from images obtained using a Hasselblad A6D-100C 100 megapixel digital mapping camera deployed within a pod mounted on the landing gear of a Robinson R44 helicopter. Images were acquired as the helicopter transited a series of flight lines designed to providField measurements of flow depth and optical image sequences acquired from the Salcha River, Alaska, on July 25, 2019
This data release includes field measurements of flow depth and optical image sequences acquired from the Salcha River in Alaska on July 25, 2019. These data were used to develop and test a spectrally based remote sensing technique for estimating water depth from passive optical image data. The purpose of this study was to assess the feasibility of inferring water depths from optical image sequeUAS-based remotely sensed bathymetry and field measurements from the Colorado River, near Parshall Colorado, June 13, 2019
To support an investigation of the feasibility of measuring river bathymetry using remotely sensed data acquired from a small unmanned aircraft system (sUAS), remotely sensed bathymetry and field measurements were collected from two cross-sections on the Colorado River near Parshall, CO on June 13, 2019. This parent data release includes links to child pages for the following data sets: 1) LidarUAS-based remotely sensed data and field measurements from the Blue River and Colorado River, near Kremmling, Colorado, October 17-18, 2018
To support an investigation of the feasibility of measuring river bathymetry using remotely sensed data acquired from an unmanned aircraft system (UAS), several types of remotely sensed data and field measurements were collected from two cross-sections on the Blue River and two cross-sections on the Colorado River near Kremmling, Colorado, on October 17-18, 2018. This parent data release includesImage data and field measurements used to map salmon spawning locations via remote sensing, American River, California, November 5-7, 2018
This data release includes images and field measurements used to map chinook salmon spawning locations along the American River near Sacramento, California, via remote sensing; the data were collected November 5-7, 2018. The purpose of this study was to develop and test a spectrally based technique for identifying salmon spawning locations, known as redds, from various types of remotely sensed daAerial photographs from the Yampa and Little Snake Rivers in northwest Colorado used to characterize channel changes occurring between 1954 and 1961
Aerial photographs of the Yampa and Little Snake Rivers acquired in 1954 and 1961 were used to examine channel changes occurring along these two rivers during this time period. In addition, these data were used to develop and test a generalizable new approach to characterizing the uncertainty associated with analyses of channel change based on time series of remotely sensed data, which we term th - Publications
Filter Total Items: 42
Capacity of two Sierra Nevada rivers for reintroduction of anadromous salmonids: Insights from a high-resolution view
Historically, anadromous steelhead Oncorhynchus mykiss and spring-run Chinook Salmon O. tshawytscha used high-elevation rivers in the Sierra Nevada of California but were extirpated in the 20th century by construction of impassable dams. Plans to reintroduce the fish by opening migratory passage across the dams and reservoirs can only succeed if upstream habitats have the capacity to support viablAuthorsDavid A. Boughton, Lee R. Harrison, Sara N. John, Rosealea M. Bond, Colin L. Nicol, Carl J. Legleiter, Ryan T. RichardsonDepths inferred from velocities estimated by remote sensing: A flow resistance equation-based approach to mapping multiple river attributes at the reach scale
Remote sensing of flow conditions in stream channels could facilitate hydrologic data collection, particularly in large, inaccessible rivers. Previous research has demonstrated the potential to estimate flow velocities in sediment-laden rivers via particle image velocimetry (PIV). In this study, we introduce a new framework for also obtaining bathymetric information: Depths Inferred from VelocitieAuthorsCarl J. Legleiter, Paul J. KinzelSurface flow velocities from space: Particle image velocimetry of satellite video of a large, sediment-laden river
Conventional, field-based streamflow monitoring in remote, inaccessible locations such as Alaska poses logistical challenges. Safety concerns, financial considerations, and a desire to expand water-observing networks make remote sensing an appealing alternative means of collecting hydrologic data. In an ongoing effort to develop non-contact methods for measuring river discharge, we evaluated the pAuthorsCarl J. Legleiter, Paul J. KinzelImproving remotely sensed river bathymetry by image-averaging
Basic data on river bathymetry is critical for numerous applications in river research and management and is increasingly obtained via remote sensing, but the noisy, pixelated appearance of image‐derived depth maps can compromise subsequent analyses. We hypothesized that this noise originates from reflectance from an irregular water surface and introduced a framework for mitigating these effects bAuthorsCarl J. Legleiter, Paul J. KinzelThe optical river bathymetry toolkit
Spatially distributed information on water depth is essential for many applications in river research and management and, under certain circumstances, can be inferred from remotely sensed data. Although fluvial remote sensing has emerged as a rapidly developing subdiscipline of the riverine sciences, more widespread adoption of these techniques has been hindered by a lack of accessible software. TAuthorsCarl J. LegleiterField evaluation of a compact, polarizing topo‐bathymetric lidar across a range of river conditions
This paper summarizes field trials to evaluate the performance of a prototype compact topo‐bathymetric lidar sensor for surveying rivers. The sensor uses a novel polarization technique to distinguish between laser returns from the water surface and streambed and its size and weight permit deployment from a small unmanned aerial system (sUAS) or a boat. Field testing was designed to identify the raAuthorsPaul J. Kinzel, Carl J. Legleiter, Paul GramsAssessing the potential for spectrally based remote sensing of salmon spawning locations
Remote sensing tools are increasingly used for quantitative mapping of fluvial habitats, yet few techniques exist for continuous sampling of aquatic organisms, such as spawning salmonids. This study assessed the potential for spectrally based remote sensing of salmon spawning locations (i.e., redds) using data acquired from unmanned aircraft systems (UAS) along a large, gravel‐bed river. We develoAuthorsLee R. Harrison, Carl J. Legleiter, Brandon T. Overstreet, Tomoko Bell, John HannonMeasuring channel planform change from image time series: A generalizable, spatially distributed, probabilistic method for quantifying uncertainty
Channels change in response to natural or anthropogenic fluctuations in streamflow and/or sediment supply and measurements of channel change are critical to many river management applications. Whereas repeated field surveys are costly and time‐consuming, remote sensing can be used to detect channel change at multiple temporal and spatial scales. Repeat images have been widely used to measure long‐AuthorsChristina Leonard, Carl J. Legleiter, Devin M. Lea, John C. SchmidtInferring surface flow velocities in sediment-laden Alaskan rivers from optical image sequences acquired from a helicopter
The remote, inaccessible location of many rivers in Alaska creates a compelling need for remote sensing approaches to streamflow monitoring. Motivated by this objective, we evaluated the potential to infer flow velocities from optical image sequences acquired from a helicopter deployed above two large, sediment-laden rivers. Rather than artificial seeding, we used an ensemble correlation particleAuthorsCarl J. Legleiter, Paul J. KinzelAn experimental evaluation of the feasibility of inferring concentrations of a visible tracer dye from remotely sensed data in turbid rivers
The movement of contaminants and biota within river channels is influenced by the flow field via various processes of dispersion. Understanding and modeling of these processes thus can facilitate applications ranging from the prediction of travel times for spills of toxic materials to the simulation of larval drift for endangered species of fish. A common means of examining dispersion in rivers iAuthorsCarl J. Legleiter, Paul Manley, Susannah O. Erwin, Edward A. BullinerRemote sensing of tracer dye concentrations to support dispersion studies in river channels
In river channels the flow field influences the dispersion of biota, contaminants, and other suspended or dissolved materials. Insight on patterns and rates of dispersion can be gained by injecting a pulse of visible dye and observing spatial and temporal variations in dye concentration as the pulse moves downstream. We evaluated the potential of passive optical remote sensing to enhance such tracAuthorsCarl J. Legleiter, Richard R. McDonald, Jonathan M. Nelson, Paul J. Kinzel, Ryan L. Perroy, Donghae Baek, Il Won SeoPhysical controls on salmon redd site selection in restored reaches of a regulated, gravel-bed river
Large‐scale river restoration programs have emerged recently as a tool for improving spawning habitat for native salmonids in highly altered river ecosystems. Few studies have quantified the extent to which restored habitat is utilized by salmonids, which habitat features influence redd site selection, or the persistence of restored habitat over time. We investigated fall‐run Chinook salmon spawniAuthorsLee R. Harrison, Erin Bray, Brandon T. Overstreet, Carl J. Legleiter, Rocko A. Brown, Joseph E. Merz, Roselea M. Bond, Colin L Nicol, Thomas Dunne - Software