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
Visualization of drifting buoy deployments on St. Clair River near public water intakes - October 3-5, 2000
Optimal estimation of suspended-sediment concentrations in streams
Steady-state flow distribution and monthly flow duration in selected branches of St. Clair and Detroit rivers within the Great Lakes waterway
A temporal and spatial analysis of ground-water levels for effective monitoring in Huron County, Michigan
Indirect ground-water discharge to the Great Lakes
Estimating ice-affected streamflow by extended Kalman filtering
Streambed stability and scour potential at selected bridge sites in Michigan
Assessment of ground-water vulnerability to atrazine leaching in Kent County, Michigan; review, comparison of results of other studies and verification
Vulnerability of ground water to atrazine leaching in Kent County, Michigan
Ground-water flow in the Saginaw aquifer in the vicinity of the north Lansing well field, Lansing Michigan — Part 1, simulations with a regional model
Ground-water flow in the Saginaw aquifer in the vicinity of the north Lansing well field, Lansing Michigan — Part 2, simulations with a regional model using a reduced cell size
A generalized estimate of ground-water-recharge rates in the Lower Peninsula of Michigan
Science and Products
- Science
- Data
- Publications
Filter Total Items: 48
Visualization of drifting buoy deployments on St. Clair River near public water intakes - October 3-5, 2000
St. Clair River is a connecting channel of the Great Lakes between Lake Huron and Lake St. Clair. The river forms part of the international boundary between the United States and Canada in the eastern Lower Peninsula of Michigan and southern Ontario. Drifting buoys were deployed to help investigate flow characteristics near public water intakes in ten reaches of St. Clair River from October 3-5, 2AuthorsDavid J. Holtschlag, Stephen S. AicheleOptimal estimation of suspended-sediment concentrations in streams
Optimal estimators are developed for computation of suspended-sediment concentrations in streams. The estimators are a function of parameters, computed by use of generalized least squares, which simultaneously account for effects of streamflow, seasonal variations in average sediment concentrations, a dynamic error component, and the uncertainty in concentration measurements. The parameters are usAuthorsD. J. HoltschlagSteady-state flow distribution and monthly flow duration in selected branches of St. Clair and Detroit rivers within the Great Lakes waterway
St. Clair and Detroit Rivers are connecting channels between Lake Huron and Lake Erie in the Great Lakes waterway, and form part of the boundary between the United States and Canada. St. Clair River, the upper connecting channel, drains 222,400 square miles and has an average flow of about 182,000 cubic feet per second. Water from St. Clair River combines with local inflows and discharges into LakAuthorsD. J. Holtschlag, J.A. KoschikA temporal and spatial analysis of ground-water levels for effective monitoring in Huron County, Michigan
Quarterly water-level measurements were analyzed to assess the effectiveness of a monitoring network of 26 wells in Huron County, Michigan. Trends were identified as constant levels and autoregressive components were computed at all wells on the basis of data collected from 1993 to 1997, using structural time series analysis. Fixed seasonal components were identified at 22 wells and outliers wereAuthorsDavid J. Holtschlag, M.J. SweatIndirect ground-water discharge to the Great Lakes
Estimates of the average ground-water component of streamflow for 195 streams in the United States part of the Great Lakes Basin range from 25 to 97 percent. Among the selected streams, the average ground-water component of streamflow was 67.3 percent. Estimates of the ground-water component of streamflow are based on hydrograph separation of 5,735 years of daily streamflow data. Incorporation ofAuthorsDavid J. Holtschlag, J.R. NicholasEstimating ice-affected streamflow by extended Kalman filtering
An extended Kalman filter was developed to automate the real-time estimation of ice-affected streamflow on the basis of routine measurements of stream stage and air temperature and on the relation between stage and streamflow during open-water (ice-free) conditions. The filter accommodates three dynamic modes of ice effects: sudden formation/ablation, stable ice conditions, and eventual eliminatioAuthorsD. J. Holtschlag, M.S. GrewalStreambed stability and scour potential at selected bridge sites in Michigan
Contraction scour in the main stream channel at a bridge and local scour near piers and abutments can result in bridge failure. Estimates of contraction-scour and local-scour potentials associated with the 100-year flood were computed for 13 bridge sites in Michigan by use of semi-theoretical equations and procedures recommended by the Federal Highway Administration. These potentials were comparedAuthorsD. J. Holtschlag, R. L. MillerAssessment of ground-water vulnerability to atrazine leaching in Kent County, Michigan; review, comparison of results of other studies and verification
Model assumptions and parameters used in an earlier study of the vulnerability of ground water in Kent County, Michigan, to atrazine contamination were reviewed and compared with other studies. The review indicated that model assumptions are consistent with those used in other models and that the parameters assigned in the Kent County model are within the broad range commonly found in the literatuAuthorsD. J. Holtschlag, C. L. LuukkonenVulnerability of ground water to atrazine leaching in Kent County, Michigan
A steady-state model of pesticide leaching through the unsaturated zone was used with readily available hydrologic, lithologic, and pesticide characteristics to estimate the vulnerability of the near-surface aquifer to atrazine contamination from non-point sources in Kent County, Michigan. The modelcomputed fraction of atrazine remaining at the water table, RM, was used as the vulnerability criterAuthorsD. J. Holtschlag, C. L. LuukkonenGround-water flow in the Saginaw aquifer in the vicinity of the north Lansing well field, Lansing Michigan — Part 1, simulations with a regional model
Vinyl chloride has been detected in water from the Saginaw aquifer near Lansing Board of Water and Light wells in the north Lansing well field. These public-supply wells have the potential to withdraw contaminated ground water. Groundwater-flow simulations and particle-tracking analyses with a regional model were used to investigate local ground-water movement. The effectiveness of hypothetical puAuthorsC. L. Luukkonen, N.G. Grannemann, D. J. HoltschlagGround-water flow in the Saginaw aquifer in the vicinity of the north Lansing well field, Lansing Michigan — Part 2, simulations with a regional model using a reduced cell size
Vinyl chloride has been detected in water from the Saginaw aquifer near Lansing Board of Water and Light wells in the north Lansing well field. These public-supply wells have the potential to withdraw contaminated ground water. The effects of reduced grid spacing for the existing TriCounty regional ground-water-flow model on local ground-water movement were investigated. This refinement of the griAuthorsC. L. Luukkonen, N.G. Grannemann, D. J. HoltschlagA generalized estimate of ground-water-recharge rates in the Lower Peninsula of Michigan
Ground-water recharge rates were estimated by analysis of streamflow, precipitation, and basin-characteristics data. Streamflow data were partitioned into ground-water-discharge and surface-water-runoff components. Regression equations relate ground-water discharge to precipitation at each basin. Basin-characteristics and long-term precipitation data were used to aid in the interpolation of recharAuthorsDavid J. Holtschlag - 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