Greg Koltun
Greg is an Emeritus Hydrologist and surface-water specialist for the Ohio-Kentucky-Indiana Water Science Center.
He received a B.S. in microbiology and an M.S. in civil engineering from the Ohio State University and has worked on a wide array of research, including topics in hydrology, hydraulics, water quality, water use, modeling, and applied statistics. Greg teaches a USGS national training course on sediment and chemical loading computation methods and was an adjunct professor at the Ohio State University where he taught applied hydrology.
Science and Products
Grand River near Painesville, OH
Huron River near Milan, OH
Black River at Elyria, OH
Cuyahoga River at Independence, OH
Phosphorus, nitrogen, and suspended-sediment loads measured at the Great Lakes Restoration Initiative tributary monitoring network: Water years 2011–2020
Model data archive—Trends in Selected Environmental, Anthropogenic, and Water-Quality Characteristics in the Upper White River Basin, Indiana, 1991–2020
Dataset for Analyses in Assessment of Runoff Volume Reduction Associated with Soil Amendments Added to Portions of Highway Median-Strip Catchments in Ohio
Total suspended solids, total phosphorus, nitrate plus nitrite, and total Kjeldahl nitrogen concentration data for the White River at Muncie, Indiana, 1991-2017
Geospatial Tools Effectively Estimate Nonexceedance Probabilities of Daily Streamflow at Ungaged and Intermittently Gaged Locations in Ohio: Data Release
Potential drivers of change in fluxes of nutrients and total suspended solids in the upper White River Basin, Indiana, Water Years 1997–2019
Trends in environmental, anthropogenic, and water-quality characteristics in the upper White River Basin, Indiana
Assessment of runoff volume reduction associated with soil amendments added to portions of highway median-strip catchments in Ohio, 2018–20
Estimated total phosphorus loads for selected sites on Great Lakes tributaries, water years 2014–2018
Trends in streamflow, nutrients, and total suspended solids in the Upper White River Basin, Indiana
Trends in streamflow and concentrations and flux of nutrients and total suspended solids in the Upper White River at Muncie, near Nora, and near Centerton, Indiana
Flood-frequency estimates for Ohio streamgages based on data through water year 2015 and techniques for estimating flood-frequency characteristics of rural, unregulated Ohio streams
Geospatial tools effectively estimate nonexceedance probabilities of daily streamflow at ungauged and intermittently gauged locations in Ohio
Estimation of upstream water use with Ohio’s StreamStats application
Hydrologic and hydraulic analyses for the Black Fork Mohican River Basin in and near Shelby, Ohio
Hydrologic effects of potential changes in climate, water use, and land cover in the Upper Scioto River Basin, Ohio
An evaluation of the accuracy of modeled and computed streamflow time-series data for the Ohio River at Hannibal Lock and Dam and at a location upstream from Sardis, Ohio
Culvert Analysis Program (CAP) version 2021.0.0
GCLAS (Graphical Constituent Loading Analysis System): A tool for computing loads of constituents transported in rivers
GCLAS is a program designed to compute daily and annual loadings of constituents transported in rivers.
Science and Products
Grand River near Painesville, OH
Huron River near Milan, OH
Black River at Elyria, OH
Cuyahoga River at Independence, OH
Phosphorus, nitrogen, and suspended-sediment loads measured at the Great Lakes Restoration Initiative tributary monitoring network: Water years 2011–2020
Model data archive—Trends in Selected Environmental, Anthropogenic, and Water-Quality Characteristics in the Upper White River Basin, Indiana, 1991–2020
Dataset for Analyses in Assessment of Runoff Volume Reduction Associated with Soil Amendments Added to Portions of Highway Median-Strip Catchments in Ohio
Total suspended solids, total phosphorus, nitrate plus nitrite, and total Kjeldahl nitrogen concentration data for the White River at Muncie, Indiana, 1991-2017
Geospatial Tools Effectively Estimate Nonexceedance Probabilities of Daily Streamflow at Ungaged and Intermittently Gaged Locations in Ohio: Data Release
Potential drivers of change in fluxes of nutrients and total suspended solids in the upper White River Basin, Indiana, Water Years 1997–2019
Trends in environmental, anthropogenic, and water-quality characteristics in the upper White River Basin, Indiana
Assessment of runoff volume reduction associated with soil amendments added to portions of highway median-strip catchments in Ohio, 2018–20
Estimated total phosphorus loads for selected sites on Great Lakes tributaries, water years 2014–2018
Trends in streamflow, nutrients, and total suspended solids in the Upper White River Basin, Indiana
Trends in streamflow and concentrations and flux of nutrients and total suspended solids in the Upper White River at Muncie, near Nora, and near Centerton, Indiana
Flood-frequency estimates for Ohio streamgages based on data through water year 2015 and techniques for estimating flood-frequency characteristics of rural, unregulated Ohio streams
Geospatial tools effectively estimate nonexceedance probabilities of daily streamflow at ungauged and intermittently gauged locations in Ohio
Estimation of upstream water use with Ohio’s StreamStats application
Hydrologic and hydraulic analyses for the Black Fork Mohican River Basin in and near Shelby, Ohio
Hydrologic effects of potential changes in climate, water use, and land cover in the Upper Scioto River Basin, Ohio
An evaluation of the accuracy of modeled and computed streamflow time-series data for the Ohio River at Hannibal Lock and Dam and at a location upstream from Sardis, Ohio
Culvert Analysis Program (CAP) version 2021.0.0
GCLAS (Graphical Constituent Loading Analysis System): A tool for computing loads of constituents transported in rivers
GCLAS is a program designed to compute daily and annual loadings of constituents transported in rivers.