David J Holtschlag, PStat
Starting in 1976, I have had a successful and enjoyable career as a hydrologist with the USGS. During more than 40 years, I participated in numerous field and research studies to characterize water resources in Michigan and parts of the Great Lakes. I am grateful and indebted to my colleagues for their professionalism, inspiration, and helpfulness.
David actively serves as an USGS Scientist Emeritus.
Professional Studies/Experience
Served as the Surface-Water Specialist for the USGS Michigan Water Science Center. Developed both 1- and 2-dimensional hydrodynamic models of surface-water bodies on the Great Lakes Waterway, Ohio River, and numerous rivers in Michigan. An unsteady 1-dimensional model of St. Clair River was developed to quantify changes in conveyance properties along individual reaches of the river using water-level gaging station data distributed throughout St. Clair River. A 2-dimensional model of St. Clair-Detroit River was developed to identify source areas to public-water intakes. A two-dimension model of the Ohio River was used to characterize flow and the dispersion of point discharge constituents based on a study using dye injections. Carried out flood frequency analysis and flood hydraulic analysis using standard models. Developed an Bayesian network model of multivariate water-quality constituents on the White River in Indiana to estimate an unmeasured subset of constituents based on an arbitrarily selected subset of measured constituents. Developed mixed effects statistical models to characterize the effects of irrigation, land use, precipitation, and temperature on selected basins in southwestern Michigan.
Mentorship/Outreach
Assisted early career hydrologists in the application of advanced statistical models including the mixed effects models and spatial models of hydrologic phenomena.
Current Interest
Development of state-space models to sequentially update parameter estimates of spline functions describing stage-discharge relations based on individual discrete-flow measurements. Apply Kalman filtering and smoothing to provide real-time and finalized estimates of the magnitudes and uncertainties of unit flow data based on unit stage data.
Education and Certifications
University of Missouri-Columbia, B.S.. in Forestry, 1974
University of Minnesota, M'S. Forest Hydrology, 1976
Michigan State University, M'S. System Science, 1990
Affiliations and Memberships*
American Statistical Association, Accredited Professional Statistician
Science and Products
Filter Total Items: 48
Detection of conveyance changes in St. Clair River using historical water-level and flow data with inverse one-dimensional hydrodynamic modeling
St. Clair River is a connecting channel that transports water from Lake Huron to the St. Clair River Delta and Lake St. Clair. A negative trend has been detected in differences between water levels on Lake Huron and Lake St. Clair. This trend may indicate a combination of flow and conveyance changes within St. Clair River. To identify where conveyance change may be taking place, eight water-level
Authors
David J. Holtschlag, C. J. Hoard
A regression model for computing index flows describing the median flow for the summer month of lowest flow in Michigan
In 2006, Michigan enacted laws to prevent new large capacity withdrawals from decreasing flows to the extent that they would functionally impair a stream's ability to support characteristic fish populations. The median streamflow for the summer month of lowest flow was specified by state decision makers as the index flow on which likely impacts of withdrawals would be assessed. At sites near long-
Authors
David A. Hamilton, Richard C. Sorrell, David J. Holtschlag
Environmental factors and flow paths related to Escherichia coli concentrations at two beaches on Lake St. Clair, Michigan, 2002–2005
Regression analyses and hydrodynamic modeling were used to identify environmental factors and flow paths associated with Escherichia coli (E. coli) concentrations at Memorial and Metropolitan Beaches on Lake St. Clair in Macomb County, Mich. Lake St. Clair is part of the binational waterway between the United States and Canada that connects Lake Huron with Lake Erie in the Great Lakes Basin. Linea
Authors
David J. Holtschlag, Dawn Shively, Richard L. Whitman, Sheridan K. Haack, Lisa R. Fogarty
Design of a national streamflow information program
No abstract available.
Authors
Jerad D. Bales, John E. Costa, David J. Holtschlag, Kenneth J. Lanfear, Stephen Lipscomb, Paul C.D. Milly, Roland J. Viger, David M. Wolock
Augmenting two-dimensional hydrodynamic simulations with measured velocity data to identify flow paths as a function of depth on Upper St. Clair River in the Great Lakes basin
Upper St. Clair River, which receives outflow from Lake Huron, is characterized by flow velocities that exceed 7 feet per second and significant channel curvature that creates complex flow patterns downstream from the Blue Water Bridge in the Port Huron, Michigan, and Sarnia, Ontario, area. Discrepancies were detected between depth-averaged velocities previously simulated by a two-dimensional (2D)
Authors
D. J. Holtschlag, J.A. Koschik
Hydrodynamic simulation and particle-tracking techniques for identification of source areas to public-water intakes on the St. Clair-Detroit River waterway in the Great Lakes Basin
Source areas to public water intakes on the St. Clair-Detroit River Waterway were identified by use of hydrodynamic simulation and particle-tracking analyses to help protect public supplies from contaminant spills and discharges. This report describes techniques used to identify these areas and illustrates typical results using selected points on St. Clair River and Lake St. Clair. Parameterizatio
Authors
David J. Holtschlag, John A. Koschik
An acoustic doppler current profiler survey of flow velocities in St. Clair River, a connecting channel of the Great Lakes
Acoustic Doppler current profilers (ADCP) were used to measure flow velocities in St. Clair River during a survey in May and June of 2002, as part of a study to assess the susceptibility of public water intakes to contaminants on the St. Clair-Detroit River Waterway. The survey provides 2.7 million point velocity measurements at 104 cross sections. Sections are spaced about 1,630 ft apart along th
Authors
David J. Holtschlag, John A. Koschik
An acoustic doppler current profiler survey of flow velocities in Detroit River, a connecting channel of the Great Lakes
Acoustic Doppler current profilers (ADCP) were used to survey flow velocities in Detroit River from July 8-19, 2002, as part of a study to assess the susceptibility of public water intakes to contaminants on the St. Clair-Detroit River Waterway. More than 3.5 million point velocities were measured at 130 cross sections. Cross sections were generally spaced about 1,800 ft apart along the river from
Authors
David J. Holtschlag, John A. Koschik
A two-dimensional hydrodynamic model of the St. Clair-Detroit River waterway in the Great Lakes basin
The St. Clair-Detroit River waterway connects Lake Huron with Lake Erie in the Great Lakes basin to form part of the international boundary between the United States and Canada. A two-dimensional hydrodynamic model is developed to compute flow velocities and water levels as part of a source water assessment of public water intakes. The model, which uses the generalized finite-element code RMA2, di
Authors
David J. Holtschlag, John A. Koschik
Visualization of drifting buoy deployments on upper Detroit River within the Great Lakes Waterway from August 28-30, 2001
Detroit River is a connecting channel on the Great Lakes waterway that joins Lake St. Clair with Lake Erie. The river forms part of the international boundary between the United States and Canada in southeastern Michigan and southern Ontario. Drifting buoys were deployed on Detroit River to help investigate flow characteristics of four selected reaches as part of a source water assessment study of
Authors
David J. Holtschlag, Steve A. Aichele
Flow distribution in selected branches of St. Clair and Detroit rivers
St. Clair and Detroit rivers, which are connecting channels between Lake Huron and Lake Erie in the Great Lakes basin, form part of the boundary between the state of Michigan and the province of Ontario. In 13 reaches, this flow divides locally around islands and dikes to form 31 branches. This study develops a set of simple linear regression equations for computing expected flow proportions in br
Authors
David J. Holtschlag, John A. Koschik
Visualization of a drifting buoy deployment on Lake St. Clair within the Great Lakes Waterway from August 12-15, 2002
Lake St. Clair is a 430 square mile lake between the state of Michigan and the province of Ontario, which forms part of the international boundary between the United States and Canada in the Great Lakes Basin. Lake St. Clair receives most of its inflow from Lake Huron through St. Clair River, which has an average flow of 182,000 cubic feet per second. The lake discharges to Detroit River, where it
Authors
David J. Holtschlag, Atiq U. Syed, Gregory W. Kennedy
Science and Products
- Science
- Data
No Result Found
- Publications
Filter Total Items: 48
Detection of conveyance changes in St. Clair River using historical water-level and flow data with inverse one-dimensional hydrodynamic modeling
St. Clair River is a connecting channel that transports water from Lake Huron to the St. Clair River Delta and Lake St. Clair. A negative trend has been detected in differences between water levels on Lake Huron and Lake St. Clair. This trend may indicate a combination of flow and conveyance changes within St. Clair River. To identify where conveyance change may be taking place, eight water-levelAuthorsDavid J. Holtschlag, C. J. HoardA regression model for computing index flows describing the median flow for the summer month of lowest flow in Michigan
In 2006, Michigan enacted laws to prevent new large capacity withdrawals from decreasing flows to the extent that they would functionally impair a stream's ability to support characteristic fish populations. The median streamflow for the summer month of lowest flow was specified by state decision makers as the index flow on which likely impacts of withdrawals would be assessed. At sites near long-AuthorsDavid A. Hamilton, Richard C. Sorrell, David J. HoltschlagEnvironmental factors and flow paths related to Escherichia coli concentrations at two beaches on Lake St. Clair, Michigan, 2002–2005
Regression analyses and hydrodynamic modeling were used to identify environmental factors and flow paths associated with Escherichia coli (E. coli) concentrations at Memorial and Metropolitan Beaches on Lake St. Clair in Macomb County, Mich. Lake St. Clair is part of the binational waterway between the United States and Canada that connects Lake Huron with Lake Erie in the Great Lakes Basin. LineaAuthorsDavid J. Holtschlag, Dawn Shively, Richard L. Whitman, Sheridan K. Haack, Lisa R. FogartyDesign of a national streamflow information program
No abstract available.AuthorsJerad D. Bales, John E. Costa, David J. Holtschlag, Kenneth J. Lanfear, Stephen Lipscomb, Paul C.D. Milly, Roland J. Viger, David M. WolockAugmenting two-dimensional hydrodynamic simulations with measured velocity data to identify flow paths as a function of depth on Upper St. Clair River in the Great Lakes basin
Upper St. Clair River, which receives outflow from Lake Huron, is characterized by flow velocities that exceed 7 feet per second and significant channel curvature that creates complex flow patterns downstream from the Blue Water Bridge in the Port Huron, Michigan, and Sarnia, Ontario, area. Discrepancies were detected between depth-averaged velocities previously simulated by a two-dimensional (2D)AuthorsD. J. Holtschlag, J.A. KoschikHydrodynamic simulation and particle-tracking techniques for identification of source areas to public-water intakes on the St. Clair-Detroit River waterway in the Great Lakes Basin
Source areas to public water intakes on the St. Clair-Detroit River Waterway were identified by use of hydrodynamic simulation and particle-tracking analyses to help protect public supplies from contaminant spills and discharges. This report describes techniques used to identify these areas and illustrates typical results using selected points on St. Clair River and Lake St. Clair. ParameterizatioAuthorsDavid J. Holtschlag, John A. KoschikAn acoustic doppler current profiler survey of flow velocities in St. Clair River, a connecting channel of the Great Lakes
Acoustic Doppler current profilers (ADCP) were used to measure flow velocities in St. Clair River during a survey in May and June of 2002, as part of a study to assess the susceptibility of public water intakes to contaminants on the St. Clair-Detroit River Waterway. The survey provides 2.7 million point velocity measurements at 104 cross sections. Sections are spaced about 1,630 ft apart along thAuthorsDavid J. Holtschlag, John A. KoschikAn acoustic doppler current profiler survey of flow velocities in Detroit River, a connecting channel of the Great Lakes
Acoustic Doppler current profilers (ADCP) were used to survey flow velocities in Detroit River from July 8-19, 2002, as part of a study to assess the susceptibility of public water intakes to contaminants on the St. Clair-Detroit River Waterway. More than 3.5 million point velocities were measured at 130 cross sections. Cross sections were generally spaced about 1,800 ft apart along the river fromAuthorsDavid J. Holtschlag, John A. KoschikA two-dimensional hydrodynamic model of the St. Clair-Detroit River waterway in the Great Lakes basin
The St. Clair-Detroit River waterway connects Lake Huron with Lake Erie in the Great Lakes basin to form part of the international boundary between the United States and Canada. A two-dimensional hydrodynamic model is developed to compute flow velocities and water levels as part of a source water assessment of public water intakes. The model, which uses the generalized finite-element code RMA2, diAuthorsDavid J. Holtschlag, John A. KoschikVisualization of drifting buoy deployments on upper Detroit River within the Great Lakes Waterway from August 28-30, 2001
Detroit River is a connecting channel on the Great Lakes waterway that joins Lake St. Clair with Lake Erie. The river forms part of the international boundary between the United States and Canada in southeastern Michigan and southern Ontario. Drifting buoys were deployed on Detroit River to help investigate flow characteristics of four selected reaches as part of a source water assessment study ofAuthorsDavid J. Holtschlag, Steve A. AicheleFlow distribution in selected branches of St. Clair and Detroit rivers
St. Clair and Detroit rivers, which are connecting channels between Lake Huron and Lake Erie in the Great Lakes basin, form part of the boundary between the state of Michigan and the province of Ontario. In 13 reaches, this flow divides locally around islands and dikes to form 31 branches. This study develops a set of simple linear regression equations for computing expected flow proportions in brAuthorsDavid J. Holtschlag, John A. KoschikVisualization of a drifting buoy deployment on Lake St. Clair within the Great Lakes Waterway from August 12-15, 2002
Lake St. Clair is a 430 square mile lake between the state of Michigan and the province of Ontario, which forms part of the international boundary between the United States and Canada in the Great Lakes Basin. Lake St. Clair receives most of its inflow from Lake Huron through St. Clair River, which has an average flow of 182,000 cubic feet per second. The lake discharges to Detroit River, where itAuthorsDavid J. Holtschlag, Atiq U. Syed, Gregory W. Kennedy - Software
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government