Paul Grams is a geomorphologist at the Southwest Biological Science Center's field station, Grand Canyon Monitoring and Research Center. He manages a set of projects collectively called the River Geomorphology and Geomorphic Change project. These include a range of studies that describe, quantify, and predict geomorphic change, mostly on large rivers in the western United States.&nb
Paul Grams received a BA in Geology from Middlebury College (1991), an M.S. in Geology from Utah State University (1997), and a Ph.D. in Geography and Environmental Engineering from Johns Hopkins University (2006). For an undergraduate thesis, Paul examined the effects of Hells Canyon Dam on the hydrology and downstream physical resources of the Snake River in Idaho. Since that time he has studied the interaction between human-induced changes in hydrology and channel form on many segments of the Green River in Utah and Colorado, small streams in northern Utah and southern Idaho, and the Colorado River in Grand Canyon. Paul’s current research interests are in fluvial geomorphology, sediment transport, the downstream effects of dams and diversions, and the connections between physical processes and ecological systems on large rivers. Paul is currently a research hydrologist at the Grand Canyon Monitoring and Research Center and manages several projects related to geomorphology, sediment budgets, and the effects of controlled floods on the Colorado River in Grand Canyon and in other parts of the Colorado River Basin.
Science and Products
Is timing really everything? Evaluating Resource Response to Spring Disturbance Flows
River Geomorphology and Geomorphic Change
Sediment Storage in Grand Canyon
River Campsites in Grand Canyon National Park
High-Flow Experiments on the Colorado River
Mapping Land-Use, Hazard Vulnerability and Habitat Suitability Using Deep Neural Networks
Grand Canyon Sandbar Monitoring
Sediment Storage in the Colorado River
Evaluation of UAS photogrammetry and comparison to ground and aerial surveys for monitoring geomorphic condition of fine sediment deposits along the Colorado River
Aerial images, digital elevation models, channel width maps, and river metrics along the Colorado River in Canyonlands National Park, Utah (1940 - 2018)
Digital elevation models and water surface profiles for the Colorado River in Cataract Canyon, Canyonlands National Park and Glen Canyon National Recreation Area, Utah
Channel mapping Glen Canyon Dam to Lees Ferry in Glen Canyon National Recreation Area, Arizona - Data
Repeat measurements of bathymetry, streamflow velocity and sediment concentration made during a high flow experiment on the Colorado River in Grand Canyon, March 2008
Long-term sandbar monitoring data along the Colorado River in Marble and Grand Canyons, Arizona
Tributary sand input data, Colorado River, Grand Canyon National Park, Arizona
Suspended-sediment, bed-sediment, and in-channel topographical data at the Green River at Mineral Bottom near Canyonlands National Park, and Colorado River at Potash, UT stream gages
Channel Mapping of the Colorado River in Grand Canyon National Park, Arizona, May 2012, river miles 29 to 62 - Data
Measurements of bed grain size on the Colorado River in Grand Canyon National Park, Arizona - 2000 to 2014
Geomorphic data for the Green River in Canyonlands, Utah, USA (ver. 1.0, June 2020)
Channel narrowing data for the lower Green River in the Canyonlands region, Utah, USA
Colorado River Eddy Sandbar Dynamics Data
Waterfalls in reservoirs: Tracking the development of nickpoints in the sediments of declining reservoirs
Proceedings of the Fiscal Year 2022 Annual Reporting Meeting to the Glen Canyon Dam Adaptive Management Program
Mapping 2-D bedload rates throughout a sand-bed river reach from high-resolution acoustical surveys of migrating bedforms
Channel mapping of the Colorado River from Glen Canyon Dam to Lees Ferry in Glen Canyon National Recreation Area, Arizona
Multi-decadal sandbar response to flow management downstream from a large dam—The Glen Canyon Dam on the Colorado River in Marble and Grand Canyons, Arizona
Effects of flow regulation and drought on geomorphology and floodplain habitat along the Colorado River in Canyonlands National Park, Utah
The effects of requested flows for native fish on sediment dynamics, geomorphology, and riparian vegetation for the Green River in Canyonlands National Park, Utah
An eddy-resolving numerical model to study turbulent flow, sediment and bed evolution using detached eddy simulation in a lateral separation zone at the field-scale
Hydrologic and geomorphic effects on riparian plant species occurrence and encroachment: Remote sensing of 360 km of the Colorado River in Grand Canyon
A morphodynamic model to evaluate long-term sandbar rebuilding using controlled floods in the Grand Canyon
Field evaluation of a compact, polarizing topo‐bathymetric lidar across a range of river conditions
Geometry of obstacle marks at instream boulders-Integration of laboratory investigations and field observations
Science and Products
- Science
Is timing really everything? Evaluating Resource Response to Spring Disturbance Flows
Glen Canyon Dam has altered ecological processes of the Colorado River in Grand Canyon. Before the dam was built, the Colorado River experienced seasonable variable flow rates, including springtime flooding events. These spring floods scoured the river bottom and enhanced natural processes that sustained the Colorado River ecosystem. Since the dam’s construction in 1963, springtime floods have...River Geomorphology and Geomorphic Change
River channels and their adjacent floodplains are ever evolving in form and composition in response to changing patterns of streamflow, the quantity and size of supplied sediment, and feedbacks with the riparian and aquatic ecosystems. Changes in channel form affect aquatic and riparian habitats, which are important for plants, animals, and insects. Erosion and deposition of river channels and...Sediment Storage in Grand Canyon
The sandbars exposed along the shoreline of the Colorado River represent only a small fraction of the sand deposits in Grand Canyon, most of which are on the bed of the river in eddies and the channel. Current management practice includes efforts to maintain and build sandbars by releasing high flows from Glen Canyon Dam that are timed to coincide with periods of fine-sediment supply from...River Campsites in Grand Canyon National Park
Sandbars have been used as campsites by river runners and hikers since the first expeditions to the region more than 100 years ago. Sandbar campsites continue to be an important part of the recreational experience for the more than 25,000 hikers and river runners that visit the Colorado River corridor each year. Because the Colorado River is dominated by bedrock cliffs and steep talus slopes...High-Flow Experiments on the Colorado River
Glen Canyon Dam has altered flow and fine sediment (sand, silt, and clay) dynamics of the Colorado River in Grand Canyon. Before the dam, the Colorado River experienced highly variable flows and carried a large amount of sediment through Grand Canyon, which maintained sandbars (highly valued camping areas in Grand Canyon) and provided sand that protected archeological and cultural sites from...Mapping Land-Use, Hazard Vulnerability and Habitat Suitability Using Deep Neural Networks
Deep learning is a computer analysis technique inspired by the human brain’s ability to learn. It involves several layers of artificial neural networks to learn and subsequently recognize patterns in data, forming the basis of many state-of-the-art applications from self-driving cars to drug discovery and cancer detection. Deep neural networks are capable of learning many levels of abstraction, an...Grand Canyon Sandbar Monitoring
Since the completion of Glen Canyon Dam in 1963, the amount of sand supplied to Grand Canyon National Park has been reduced by more than 90 percent. The Paria River, a tributary to the Colorado River 15 miles downstream from the dam, is now the single most important supplier of sand to the Colorado River within the Park. This large reduction in sand supply has resulted in substantial decrease in...Sediment Storage in the Colorado River
The sandbars exposed along the shoreline of the Colorado River represent only a small fraction of the sand deposits in Grand Canyon, most of which are on the bed of the river in eddies and the channel. Current management practice includes efforts to maintain and build sandbars by releasing high flows from Glen Canyon Dam that are timed to coincide with periods of fine-sediment supply from...Evaluation of UAS photogrammetry and comparison to ground and aerial surveys for monitoring geomorphic condition of fine sediment deposits along the Colorado River
At the Grand Canyon Monitoring and Research Center (GCMRC), we are looking for affordable and efficient alternatives and augmentations to our current approaches to monitoring the geomorphic condition of sandbars, terraces and other fine-sediment deposits along the Colorado River in the Grand Canyon region, Arizona. - Data
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Aerial images, digital elevation models, channel width maps, and river metrics along the Colorado River in Canyonlands National Park, Utah (1940 - 2018)
These data consist of rectified aerial photographs, measurements of active channel width, measurements of river and floodplain bathymetry and topography, and ancillary data. These data are specific to the corridor of the Colorado River in Canyonlands National Park between Potash, Utah and the confluence of the Green and Colorado Rivers near Spanish Bottom, Utah. The time period for these data areDigital elevation models and water surface profiles for the Colorado River in Cataract Canyon, Canyonlands National Park and Glen Canyon National Recreation Area, Utah
These data consist of measurements of riverbed and floodplain bathymetry and topography, measurements of water-surface elevations and ancillary data. These data are specific to the corridor of the Colorado River from the confluence of the Green and Colorado Rivers near Spanish Bottom, Utah in Canyonlands National Park to the confluence with the Dirty Devil River in Glen Canyon National RecreationChannel mapping Glen Canyon Dam to Lees Ferry in Glen Canyon National Recreation Area, Arizona - Data
Bathymetric, topographic, and grain-size data were collected from May 2013 to October 2016 along a 15-mi reach of the Colorado River in Glen Canyon National Recreation Area, Arizona by the U.S. Geological Survey Grand Canyon Monitoring and Research Center. The study reach is located from river miles -15 at the base of Glen Canyon Dam to 0 at Lees Ferry. Channel bathymetry was mapped using multibeaRepeat measurements of bathymetry, streamflow velocity and sediment concentration made during a high flow experiment on the Colorado River in Grand Canyon, March 2008
The acoustic Doppler current profiler (ADCP) data were collected and compiled to characterize the velocity patterns in channel of the Colorado River and in an adjacent zone of laterally recirculating flow (eddy). Topographic/bathymetric digital elevation models (DEMs) were collected and compiled to characterize erosion and deposition in the Colorado River and in an adjacent zone of laterally recirLong-term sandbar monitoring data along the Colorado River in Marble and Grand Canyons, Arizona
This data release comprises nearly three decades of measurements of sandbar topography for monitoring sites along the Colorado River in Grand Canyon National Park and Glen Canyon National Recreation Area. The data were collected to monitor the effects of the operations of Glen Canyon Dam on sandbars, which are also recreational campsites. The data were collected by the US Geological Survey GrandTributary sand input data, Colorado River, Grand Canyon National Park, Arizona
These data were compiled from sampling pre-dam flood terraces and sand bar deposits of the Colorado River in Glen Canyon between Glen Canyon Dam and the Paria River confluence. This includes sand deposits from the 2008, 2012, 2013 and 2014 high flow experiments (HFE) in Marble Canyon. Sand sources from these locations were sampled in September/October of 2013 and 2014. Also, samples of suspended sSuspended-sediment, bed-sediment, and in-channel topographical data at the Green River at Mineral Bottom near Canyonlands National Park, and Colorado River at Potash, UT stream gages
Sediment Data: These data include (1) physical suspended-sediment sample data including suspended silt and clay concentration, suspended-sand concentration, and suspended-sand grain size distribution, (2) bed-sediment sample data with complete grain size analyses, and (3) 15-minute acoustical sediment data measured using a multifrequency array (1MHz and 2MHz) of sidelooking acoustic Doppler profilChannel Mapping of the Colorado River in Grand Canyon National Park, Arizona, May 2012, river miles 29 to 62 - Data
Bathymetric, topographic, and grain-size data were collected in May 2012 along a 33-mi reach of the Colorado River in Grand Canyon National Park, Arizona. The study reach is located from river miles 29 to 62 at the confluence of the Colorado and Little Colorado Rivers. Channel bathymetry was mapped using multibeam and singlebeam echosounders, subaerial topography was mapped using ground-based totaMeasurements of bed grain size on the Colorado River in Grand Canyon National Park, Arizona - 2000 to 2014
These data were compiled to better understand sedimentation patterns on the bed of the Colorado River in Grand Canyon National Park, and the way these patterns relate to suspended sediment grain size and concentration. These data were collected by the US Geological Survey Grand Canyon Monitoring and Research Center from 2000 to 2014, primarily using the "Flying Eyeball" underwater imaging system.Geomorphic data for the Green River in Canyonlands, Utah, USA (ver. 1.0, June 2020)
These data consist of rectified aerial photographs, measurements of active channel width, measurements of river and floodplain bathymetry and topography, and ancillary data. These data are specific to the corridor of the Green River in Canyonlands National Park between Horseshoe Canyon and Deadhorse Canyon, Utah. The time period for these data are 1940 to 2018. The 'Channel Width' shapefile data aChannel narrowing data for the lower Green River in the Canyonlands region, Utah, USA
The 'Channel Width' shapefile data are measurements of the active channel width of the Green River at 1-km intervals in and near Canyonlands National Park, Utah. The active channel was defined as the area of the wetted, or inundated, channel as visible on aerial photographs plus the area of bare (free of vegetation) sand and gravel bars. The active channel for each aerial photograph series was hanColorado River Eddy Sandbar Dynamics Data
These data are a compilation of the characteristics of eddy sandbars, eddy sandbar areas and volumes measured between 1990 and 2015, and longitudinal metrics of the Colorado River in Grand Canyon National Park, Arizona. These data were used to evaluate the response of sandbars to controlled floods implemented in 1996, 2004, 2008, 2012, 2013, and 2014. These data were also used to characterize the - Multimedia
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Filter Total Items: 71
Waterfalls in reservoirs: Tracking the development of nickpoints in the sediments of declining reservoirs
Recent drought has resulted in dramatic lowering of the two largest water-storage reservoirs in the western United States: Lake Powell and Lake Mead. These decreases in reservoir elevations have resulted in the re-emergence of over 100 km of the Colorado and San Juan rivers at the upstream end of Lake Powell and over 80 km of the Colorado River at the upstream end of Lake Mead. Upon reservoir loweAuthorsPaul Grams, Robert B. TussoProceedings of the Fiscal Year 2022 Annual Reporting Meeting to the Glen Canyon Dam Adaptive Management Program
(Hartwell) This report is prepared primarily to account for work conducted and products delivered in FY 2022 by GCMRC and to inform the Technical Work Group of science conducted by GCMRC and its cooperators in support of the Glen Canyon Dam Adaptive Management Program (GCDAMP). It includes a summary of accomplishments, modifications to work plans, results, and recommendations related to projects iAuthorsDavid Topping, Paul Grams, Emily C. Palmquist, Joel B. Sankey, Helen C. Fairley, Bridget Deemer, Charles Yackulic, Theodore Kennedy, Anya Metcalfe, Maria C. Dzul, David Ward, Mariah Aurelia Giardina, Lucas Bair, Thomas Gushue, Caitlin M. Andrews, Ronald E. Griffiths, David Dean, Keith Kohl, Michael J Moran, Nicholas Voichick, Thomas A. Sabol, Laura A. Tennant, Kimberly Dibble, Michael C. RungeMapping 2-D bedload rates throughout a sand-bed river reach from high-resolution acoustical surveys of migrating bedforms
This paper introduces a method for determining spatially-distributed, 2-D bedload rates using repeat, high-resolution surveys of the bed topography. As opposed to existing methods, bedform parameters and bedload rates are computed from bed elevation profiles interpolated along the local bedform velocities. The bedform velocity fields are computed applying Large-Scale Particle Image Velocimetry, inAuthorsJérôme Le Coz, Emeline Perret, Benoît Camenen, David Topping, Daniel D. Buscombe, Kate C.P. Leary, Guillaume Dramais, Paul GramsChannel mapping of the Colorado River from Glen Canyon Dam to Lees Ferry in Glen Canyon National Recreation Area, Arizona
Bathymetric and topographic data were collected from May 2013 to February 2016 along the 15.84-mile reach of the Colorado River spanning from Glen Canyon Dam to Lees Ferry in Glen Canyon National Recreation Area, Arizona. Channel bathymetry was mapped using multibeam and singlebeam echo sounders; subaerial topography was mapped using a combination of ground-based total stations and aerial photograAuthorsMatt Kaplinski, Joseph E. Hazel, Paul E. Grams, Tom Gushue, Daniel D. Buscombe, Keith KohlMulti-decadal sandbar response to flow management downstream from a large dam—The Glen Canyon Dam on the Colorado River in Marble and Grand Canyons, Arizona
Sandbars are an important resource in the Colorado River corridor in Marble and Grand Canyons, Arizona, downstream from Glen Canyon Dam. Sandbars provide aquatic and riparian habitat and are used as campsites by river runners and hikers. The study area is the Colorado River between Glen Canyon Dam and Diamond Creek, which is about 388 kilometers (241 miles) downstream from the dam. Closure of GlenAuthorsJoseph E. Hazel, Matthew A. Kaplinski, Daniel Hamill, Daniel Buscombe, Erich R. Mueller, Robert P. Ross, Keith Kohl, Paul E. GramsEffects of flow regulation and drought on geomorphology and floodplain habitat along the Colorado River in Canyonlands National Park, Utah
Streamflow regulation compounded by regional drought has resulted in up to 22% reduction in channel width, changes in channel planform, expansion of riparian vegetation, and alterations to floodplain habitat on the Colorado River in Meander Canyon, Utah. Although some changes in channel width occurred between the 1940s and 1980s, coinciding with major phases of upstream water development, larger dAuthorsPaul Grams, Eric Head, Erich R. MuellerThe effects of requested flows for native fish on sediment dynamics, geomorphology, and riparian vegetation for the Green River in Canyonlands National Park, Utah
Releases of water from Flaming Gorge Dam together with climate-related variations in runoff determine the streamflow regime of the Green River, which affects the physical characteristics of the channel and riparian ecosystem of the Green River corridor in Canyonlands National Park. The dam has decreased peak streamflows and raised base streamflows, resulting in vegetation encroachment and channelAuthorsPaul E. Grams, Jonathan M. Friedman, David Dean, David J. ToppingAn eddy-resolving numerical model to study turbulent flow, sediment and bed evolution using detached eddy simulation in a lateral separation zone at the field-scale
Turbulence-resolving simulations elucidate key elements of fluid dynamics and sediment transport in fluvial environments. This research presents a feasible strategy for applying state-of-the-art computational fluid mechanics to the study of sediment transport and morphodynamic processes in lateral separation zones, which are common features in canyon rivers where massive lateral flow separation caAuthorsLaura V. Alvarez, Paul GramsHydrologic and geomorphic effects on riparian plant species occurrence and encroachment: Remote sensing of 360 km of the Colorado River in Grand Canyon
A common impact on riparian ecosystem function following river regulation is the expansion and encroachment of riparian plant species in the active river channels and floodplain, which reduces flow of water and suspended sediment between the river, riparian area, and upland ecosystems. We characterized riparian plant species occurrence and quantified encroachment within the dam-regulated ColoradoAuthorsLaura E. Durning, Joel B. Sankey, Charles Yackulic, Paul Grams, Bradley J. Butterfield, Temuulen T. SankeyA morphodynamic model to evaluate long-term sandbar rebuilding using controlled floods in the Grand Canyon
Controlled floods released from dams have become a common restoration strategy in river systems worldwide. Here we present a morphodynamic model of sandbar volume change for a subset of sandbars of the Colorado River in Grand Canyon National Park, where controlled floods are part of a management strategy focused on sandbar maintenance. We simulate sandbars as a triangular wedge, where deposition aAuthorsErich R. Mueller, Paul GramsField 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 GramsGeometry of obstacle marks at instream boulders-Integration of laboratory investigations and field observations
Obstacle marks are instream bedforms, typically composed of an upstream frontal scour hole and a downstream sediment accumulation in the vicinity of an obstacle. Local scouring at infrastructure (e.g. bridge piers) is a well‐studied phenomenon in hydraulic engineering, while less attention is given to the time‐dependent evolution of frontal scour holes at instream boulders and their geometric relaAuthorsOliver Schlömer, Paul Grams, Daniel Buscombe, Jürgen Herget - News