Thomas A Sabol
Tom Sabol is a hydrologist with the Southwest Biological Science Center.
Science and Products
Lake Powell Research
Lake Powell is a large arid reservoir that represents about 70% of the water storage capacity for the Upper Colorado River Basin. It is the second largest reservoir in the United States by capacity (second only to Lake Mead). Lake Powell is an oligotrophic reservoir, which means that nutrient concentrations and algal production are generally low. This often results in very clear-water conditions...
River Sediment Dynamics
Sediment controls the physical habitat of river ecosystems. Changes in the amount and areal distribution of different sediment types cause changes in river-channel form and river habitat. The amount and type of sediment suspended in the water column determines water clarity. Understanding sediment transport and the conditions under which sediment is deposited or eroded from the various...
Surveyed peak-stage elevations, coordinates, and indicator data of strandlines from large floods on the Colorado River in Grand Canyon National Park, Arizona Surveyed peak-stage elevations, coordinates, and indicator data of strandlines from large floods on the Colorado River in Grand Canyon National Park, Arizona
These data provide a comprehensive survey of peak-stage indicators along the Colorado River corridor between river mile (RM) 0 and RM 87 (see Figure 1 in the associated USGS-SIR). In 2008, the locations of peak-stage indicators in three short reaches downstream from RM 87 were measured using a handheld GPS unit (see Appendix 1 in the associated USGS-SIR). Total-station measurements were...
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 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
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...
Stream Drift Sampling in Arizona, 2014Data Stream Drift Sampling in Arizona, 2014Data
These data were compiled from field drift collections and from a meta-analysis of published drift literature. Field data were collected in 2014 from the Colorado River downstream of Glen Canyon Dam, Arizona, from the Salt River downstream of Stewart Mountain Dam, Arizona, and from Wet Beaver Creek near the Village of Oak Creek, Arizona. These data represent flow meter measurements taken...
Filter Total Items: 17
Low water levels interact with reservoir aging to increase the severity of summertime metalimnion dissolved oxygen minima in Lake Powell, desert Southwest, USA Low water levels interact with reservoir aging to increase the severity of summertime metalimnion dissolved oxygen minima in Lake Powell, desert Southwest, USA
Water level drawdowns are common in reservoirs and can affect dissolved oxygen (DO) dynamics via several pathways. In large storage reservoirs, inflow deltas are often important sites for sediment deposition, with some sediment laden rivers forming highly dynamic delta regions as they enter the reservoir. As water levels change, deposited sediment may be remobilized and affect pelagic DO...
Authors
Bridget Deemer, Caitlin Andrews, Robin Reibold, Bryce Mihalevich, Thomas Sabol, Jeremiah Drewel, Charles Yackulic
Appendix 1: Lake Powell water quality monitoring Appendix 1: Lake Powell water quality monitoring
No abstract available.
Authors
Bridget Deemer, Nicholas Voichick, Thomas Sabol, Caitlin Andrews, Bryce Mihalevich
Proceedings of the Fiscal Year 2022 Annual Reporting Meeting to the Glen Canyon Dam Adaptive Management Program Proceedings 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...
Authors
David Topping, Paul Grams, Emily Palmquist, Joel B. Sankey, Helen Fairley, Bridget Deemer, Charles Yackulic, Theodore Kennedy, Anya Metcalfe, Maria Dzul, David Ward, Mariah Giardina, Lucas Bair, Thomas M. Gushue, Caitlin Andrews, Ronald Griffiths, David Dean, Keith Kohl, Michael Moran, Nicholas Voichick, Thomas Sabol, Laura Tennant, Kimberly Dibble, Michael Runge
Field investigation of sub-isokinetic sampling by the US D-96-type suspended-sediment sampler and its effect on suspended-sediment measurements Field investigation of sub-isokinetic sampling by the US D-96-type suspended-sediment sampler and its effect on suspended-sediment measurements
Collection of accurate suspended-sediment data using depth-integrating samplers requires that they operate isokinetically, that is, that they sample at the local stream velocity unaffected by the presence of the suspended-sediment sampler. Sub-isokinetic suspended-sediment sampling causes grain-size dependent positive biases in the suspended-sediment concentration measured by the...
Authors
Thomas Sabol, David J. Topping, Ronald Griffiths, Guillaume Dramais
Strandlines from large floods on the Colorado River in Grand Canyon National Park, Arizona Strandlines from large floods on the Colorado River in Grand Canyon National Park, Arizona
Strandlines of peak-stage indicators (such as driftwood logs, woody debris, and trash) provide valuable data for understanding the maximum stage and extent of inundation during floods. A series of seven strandlines have been preserved along the Colorado River in Grand Canyon National Park, Arizona, USA. A survey and analysis of these strandlines was completed from the Colorado River at...
Authors
Thomas Sabol, Ronald Griffiths, David J. Topping, Erich Mueller, Robert Tusso, Joseph Hazel
Optimal timing of high-flow experiments for sandbar deposition Optimal timing of high-flow experiments for sandbar deposition
Sediment-transport theory and field measurements indicate that the greatest or most efficient deposition of sand in eddies occurs during controlled floods (a.k.a. High-Flow Experiments or HFEs) when the greatest amount of the finest sand is available on the bed of the Colorado River (Topping and others, 2010). Conducting HFEs when the sand on the bed of the Colorado River is depleted and...
Authors
David Topping, Paul Grams, Ronald Griffiths, Joseph Hazel, Matthew Kaplinski, David Dean, Nicholas Voichick, Joel Unema, Thomas Sabol
Deleterious effects of net clogging on the quantification of stream drift Deleterious effects of net clogging on the quantification of stream drift
Drift studies are central to stream and river ecological research. However, a fundamental aspect of quantifying drift — how net clogging affects the accuracy of results — has been widely ignored. Utilizing approaches from plankton and suspended sediment studies in oceanography and hydrology, we examined the rate and dynamics of net clogging across a range of conditions. We found that...
Authors
Jeffrey Muehlbauer, Theodore A. Kennedy, Adam Copp, Thomas Sabol
Sediment supply versus local hydraulic controls on sediment transport and storage in a river with large sediment loads Sediment supply versus local hydraulic controls on sediment transport and storage in a river with large sediment loads
The Rio Grande in the Big Bend region of Texas, USA, and Chihuahua and Coahuila, Mexico, undergoes rapid geomorphic changes as a result of its large sediment supply and variable hydrology; thus, it is a useful natural laboratory to investigate the relative importance of flow strength and sediment supply in controlling alluvial channel change. We analyzed a suite of sediment transport and...
Authors
David Dean, David Topping, John Schmidt, Ronald Griffiths, Thomas Sabol
Using 15-minute acoustic data to analyze suspended-sediment dynamics in the Rio Grande in the Big Bend Region Using 15-minute acoustic data to analyze suspended-sediment dynamics in the Rio Grande in the Big Bend Region
The Rio Grande in the Big Bend region is subject to rapid geomorphic change consisting of channel narrowing during years of low flow, and channel widening during rare, large, long duration floods. Since the 1940s, there have been large declines in mean and peak stream flow, and the channel has progressively narrowed. Large, channel widening floods are infrequent and have failed to widen...
Authors
David Dean, David Topping, Ronald Griffiths, Thomas Sabol, John Schmidt, Jeffery Bennett
New information and guidance for collapsible bag-type sediment samplers New information and guidance for collapsible bag-type sediment samplers
Answers for many critical water-related issues require solid-phase water-quality data that are representative, accurate, and consistent. Collection of suspended sediment samples for subsequent analyses of solid-phase constituents that represent water-column sediment concentrations requires use of appropriate isokinetic samplers and sampling techniques (Davis, 2005a). Recent review of...
Authors
Mark Landers, Thomas Sabol, Michael Manning, Jessica Anderson, Corey Sannes
Transient simulation of groundwater levels within a sandbar of the Colorado River, Marble Canyon, Arizona, 2004 Transient simulation of groundwater levels within a sandbar of the Colorado River, Marble Canyon, Arizona, 2004
Seepage erosion and mass failure of emergent sandy deposits along the Colorado River in Grand Canyon National Park, Arizona, are a function of the elevation of groundwater in the sandbar, fluctuations in river stage, the exfiltration of water from the bar face, and the slope of the bar face. In this study, a generalized three-dimensional numerical model was developed to predict the time...
Authors
Thomas A. Sabol, Abraham E. Springer
Evaluation of intake efficiencies and associated sediment-concentration errors in US D-77 bag-type and US D-96-type depth-integrating suspended-sediment samplers Evaluation of intake efficiencies and associated sediment-concentration errors in US D-77 bag-type and US D-96-type depth-integrating suspended-sediment samplers
Accurate measurements of suspended-sediment concentration require suspended-sediment samplers to operate isokinetically, within an intake-efficiency range of 1.0 ± 0.10, where intake efficiency is defined as the ratio of the velocity of the water through the sampler intake to the local ambient stream velocity. Local ambient stream velocity is defined as the velocity of the water in the...
Authors
Thomas A. Sabol, David Topping
Science and Products
Lake Powell Research
Lake Powell is a large arid reservoir that represents about 70% of the water storage capacity for the Upper Colorado River Basin. It is the second largest reservoir in the United States by capacity (second only to Lake Mead). Lake Powell is an oligotrophic reservoir, which means that nutrient concentrations and algal production are generally low. This often results in very clear-water conditions...
River Sediment Dynamics
Sediment controls the physical habitat of river ecosystems. Changes in the amount and areal distribution of different sediment types cause changes in river-channel form and river habitat. The amount and type of sediment suspended in the water column determines water clarity. Understanding sediment transport and the conditions under which sediment is deposited or eroded from the various...
Surveyed peak-stage elevations, coordinates, and indicator data of strandlines from large floods on the Colorado River in Grand Canyon National Park, Arizona Surveyed peak-stage elevations, coordinates, and indicator data of strandlines from large floods on the Colorado River in Grand Canyon National Park, Arizona
These data provide a comprehensive survey of peak-stage indicators along the Colorado River corridor between river mile (RM) 0 and RM 87 (see Figure 1 in the associated USGS-SIR). In 2008, the locations of peak-stage indicators in three short reaches downstream from RM 87 were measured using a handheld GPS unit (see Appendix 1 in the associated USGS-SIR). Total-station measurements were...
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 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
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...
Stream Drift Sampling in Arizona, 2014Data Stream Drift Sampling in Arizona, 2014Data
These data were compiled from field drift collections and from a meta-analysis of published drift literature. Field data were collected in 2014 from the Colorado River downstream of Glen Canyon Dam, Arizona, from the Salt River downstream of Stewart Mountain Dam, Arizona, and from Wet Beaver Creek near the Village of Oak Creek, Arizona. These data represent flow meter measurements taken...
Filter Total Items: 17
Low water levels interact with reservoir aging to increase the severity of summertime metalimnion dissolved oxygen minima in Lake Powell, desert Southwest, USA Low water levels interact with reservoir aging to increase the severity of summertime metalimnion dissolved oxygen minima in Lake Powell, desert Southwest, USA
Water level drawdowns are common in reservoirs and can affect dissolved oxygen (DO) dynamics via several pathways. In large storage reservoirs, inflow deltas are often important sites for sediment deposition, with some sediment laden rivers forming highly dynamic delta regions as they enter the reservoir. As water levels change, deposited sediment may be remobilized and affect pelagic DO...
Authors
Bridget Deemer, Caitlin Andrews, Robin Reibold, Bryce Mihalevich, Thomas Sabol, Jeremiah Drewel, Charles Yackulic
Appendix 1: Lake Powell water quality monitoring Appendix 1: Lake Powell water quality monitoring
No abstract available.
Authors
Bridget Deemer, Nicholas Voichick, Thomas Sabol, Caitlin Andrews, Bryce Mihalevich
Proceedings of the Fiscal Year 2022 Annual Reporting Meeting to the Glen Canyon Dam Adaptive Management Program Proceedings 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...
Authors
David Topping, Paul Grams, Emily Palmquist, Joel B. Sankey, Helen Fairley, Bridget Deemer, Charles Yackulic, Theodore Kennedy, Anya Metcalfe, Maria Dzul, David Ward, Mariah Giardina, Lucas Bair, Thomas M. Gushue, Caitlin Andrews, Ronald Griffiths, David Dean, Keith Kohl, Michael Moran, Nicholas Voichick, Thomas Sabol, Laura Tennant, Kimberly Dibble, Michael Runge
Field investigation of sub-isokinetic sampling by the US D-96-type suspended-sediment sampler and its effect on suspended-sediment measurements Field investigation of sub-isokinetic sampling by the US D-96-type suspended-sediment sampler and its effect on suspended-sediment measurements
Collection of accurate suspended-sediment data using depth-integrating samplers requires that they operate isokinetically, that is, that they sample at the local stream velocity unaffected by the presence of the suspended-sediment sampler. Sub-isokinetic suspended-sediment sampling causes grain-size dependent positive biases in the suspended-sediment concentration measured by the...
Authors
Thomas Sabol, David J. Topping, Ronald Griffiths, Guillaume Dramais
Strandlines from large floods on the Colorado River in Grand Canyon National Park, Arizona Strandlines from large floods on the Colorado River in Grand Canyon National Park, Arizona
Strandlines of peak-stage indicators (such as driftwood logs, woody debris, and trash) provide valuable data for understanding the maximum stage and extent of inundation during floods. A series of seven strandlines have been preserved along the Colorado River in Grand Canyon National Park, Arizona, USA. A survey and analysis of these strandlines was completed from the Colorado River at...
Authors
Thomas Sabol, Ronald Griffiths, David J. Topping, Erich Mueller, Robert Tusso, Joseph Hazel
Optimal timing of high-flow experiments for sandbar deposition Optimal timing of high-flow experiments for sandbar deposition
Sediment-transport theory and field measurements indicate that the greatest or most efficient deposition of sand in eddies occurs during controlled floods (a.k.a. High-Flow Experiments or HFEs) when the greatest amount of the finest sand is available on the bed of the Colorado River (Topping and others, 2010). Conducting HFEs when the sand on the bed of the Colorado River is depleted and...
Authors
David Topping, Paul Grams, Ronald Griffiths, Joseph Hazel, Matthew Kaplinski, David Dean, Nicholas Voichick, Joel Unema, Thomas Sabol
Deleterious effects of net clogging on the quantification of stream drift Deleterious effects of net clogging on the quantification of stream drift
Drift studies are central to stream and river ecological research. However, a fundamental aspect of quantifying drift — how net clogging affects the accuracy of results — has been widely ignored. Utilizing approaches from plankton and suspended sediment studies in oceanography and hydrology, we examined the rate and dynamics of net clogging across a range of conditions. We found that...
Authors
Jeffrey Muehlbauer, Theodore A. Kennedy, Adam Copp, Thomas Sabol
Sediment supply versus local hydraulic controls on sediment transport and storage in a river with large sediment loads Sediment supply versus local hydraulic controls on sediment transport and storage in a river with large sediment loads
The Rio Grande in the Big Bend region of Texas, USA, and Chihuahua and Coahuila, Mexico, undergoes rapid geomorphic changes as a result of its large sediment supply and variable hydrology; thus, it is a useful natural laboratory to investigate the relative importance of flow strength and sediment supply in controlling alluvial channel change. We analyzed a suite of sediment transport and...
Authors
David Dean, David Topping, John Schmidt, Ronald Griffiths, Thomas Sabol
Using 15-minute acoustic data to analyze suspended-sediment dynamics in the Rio Grande in the Big Bend Region Using 15-minute acoustic data to analyze suspended-sediment dynamics in the Rio Grande in the Big Bend Region
The Rio Grande in the Big Bend region is subject to rapid geomorphic change consisting of channel narrowing during years of low flow, and channel widening during rare, large, long duration floods. Since the 1940s, there have been large declines in mean and peak stream flow, and the channel has progressively narrowed. Large, channel widening floods are infrequent and have failed to widen...
Authors
David Dean, David Topping, Ronald Griffiths, Thomas Sabol, John Schmidt, Jeffery Bennett
New information and guidance for collapsible bag-type sediment samplers New information and guidance for collapsible bag-type sediment samplers
Answers for many critical water-related issues require solid-phase water-quality data that are representative, accurate, and consistent. Collection of suspended sediment samples for subsequent analyses of solid-phase constituents that represent water-column sediment concentrations requires use of appropriate isokinetic samplers and sampling techniques (Davis, 2005a). Recent review of...
Authors
Mark Landers, Thomas Sabol, Michael Manning, Jessica Anderson, Corey Sannes
Transient simulation of groundwater levels within a sandbar of the Colorado River, Marble Canyon, Arizona, 2004 Transient simulation of groundwater levels within a sandbar of the Colorado River, Marble Canyon, Arizona, 2004
Seepage erosion and mass failure of emergent sandy deposits along the Colorado River in Grand Canyon National Park, Arizona, are a function of the elevation of groundwater in the sandbar, fluctuations in river stage, the exfiltration of water from the bar face, and the slope of the bar face. In this study, a generalized three-dimensional numerical model was developed to predict the time...
Authors
Thomas A. Sabol, Abraham E. Springer
Evaluation of intake efficiencies and associated sediment-concentration errors in US D-77 bag-type and US D-96-type depth-integrating suspended-sediment samplers Evaluation of intake efficiencies and associated sediment-concentration errors in US D-77 bag-type and US D-96-type depth-integrating suspended-sediment samplers
Accurate measurements of suspended-sediment concentration require suspended-sediment samplers to operate isokinetically, within an intake-efficiency range of 1.0 ± 0.10, where intake efficiency is defined as the ratio of the velocity of the water through the sampler intake to the local ambient stream velocity. Local ambient stream velocity is defined as the velocity of the water in the...
Authors
Thomas A. Sabol, David Topping