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
Filter Total Items: 53
Floods of June 28-29, 1998 in Ohio Floods of June 28-29, 1998 in Ohio
During a 96-hour period extending from June 26 to June 30, 1998, a stalled frontal system produced a series of storms that dumped 10 inches or more of rain on parts of Ohio. The storms occurred at the end of a relatively wet month, resulting in flooding and widespread damage throughout much of central, east-central, and southeastern Ohio. Twenty-three Ohio counties were declared Federal...
Authors
G. F. Koltun
Factors related to probability of joint flooding on paired streams in Ohio Factors related to probability of joint flooding on paired streams in Ohio
Factors related to the probability of joint flooding on paired streams were investigated. Stream pairs were considered to have flooded jointly at the design-year flood threshold (corresponding to the 2-, 10-, 25-, or 50-year instantaneous peak stream flow) if peak stream flows at both streams in the pair were observed or predicted to have equaled or exceeded the threshold on a given...
Authors
G. F. Koltun, J. M. Sherwood
Effects of hydrologic, biological, and environmental processes on sources and concentrations of fecal bacteria in the Cuyahoga River, with implications for management of recreational waters in Summit and Cuyahoga Counties, Ohio Effects of hydrologic, biological, and environmental processes on sources and concentrations of fecal bacteria in the Cuyahoga River, with implications for management of recreational waters in Summit and Cuyahoga Counties, Ohio
Discharges of fecal bacteria (fecal coliform bacteria and Escherichia coli ) to the middle main stem of the Cuyahoga River from storm water, combined sewers, and incompletely disinfected wastewater have resulted in frequent exceedances of bacteriological water-quality standards in a 23-mile reach of the river that flows through the Cuyahoga Valley National Recreation Area. Contamination...
Authors
Donna N. Myers, G. F. Koltun, Donna S. Francy
Factors related to the joint probability of flooding on paired streams Factors related to the joint probability of flooding on paired streams
The factors related to the joint probabilty of flooding on paired streams were investigated and quantified to provide information to aid in the design of hydraulic structures where the joint probabilty of flooding is an element of the design criteria. Stream pairs were considered to have flooded jointly at the design-year flood threshold (corresponding to the 2-, 10-, 25-, or 50-year...
Authors
G. F. Koltun, J. M. Sherwood
Hydrologic disturbance and response of aquatic biota in Big Darby Creek basin, Ohio Hydrologic disturbance and response of aquatic biota in Big Darby Creek basin, Ohio
Washout and recolonization of macroinvertebrates and algae associated with a spring and summer storm were measured at three sites in Ohio's Big Darby Creek Basin. Related factors, such as streamflow magnitude, shear stress, and streamed disturbance were considered when interpreting observed changes in densities and community structure of macroinvertebrates and algae. During the study...
Authors
J.A. Hambrook, G. F. Koltun, B.B. Palcsak, J.S. Tertuliani
Effects of hydrologic disturbance on washout and recolonization of stream biota Effects of hydrologic disturbance on washout and recolonization of stream biota
No abstract available
Authors
J.A. Hambrook, G. F. Koltun
Summary of floods in the United States during 1990 and 1991 Summary of floods in the United States during 1990 and 1991
This volume contains 50 articles describing severe, widespread, or unusual flooding in 28 of the 50 States during 1990 and 1991. Each flood is described to an extent commensurate with its significance and the availability of data on the hydrology and the damages. Each article includes one or more maps showing the general area of flooding. Most articles include tables of data that allow...
Authors
Paul Robert Jordan, L. J. Combs
Determination of base-flow characteristics at selected streamflow-gaging stations on the Mad River, Ohio Determination of base-flow characteristics at selected streamflow-gaging stations on the Mad River, Ohio
This report describes the results of a study to estimate characteristics of base flow and sustained ground-water discharge at five streamflow-gaging stations on the Mad River in Ohio. The five streamflow-gaging stations are located at Zanesfield, near Urbana, at St. Paris Pike (at Eagle City), near Springfield, and near Dayton. The median of the annual-mean base flows, determined by...
Authors
G. F. Koltun
User's manual for SEDCALC, a computer program for computation of suspended-sediment discharge User's manual for SEDCALC, a computer program for computation of suspended-sediment discharge
Sediment-Record Calculations (SEDCALC), a menu-driven set of interactive computer programs, was developed to facilitate computation of suspended-sediment records. The programs comprising SEDCALC were developed independently in several District offices of the U.S. Geological Survey (USGS) to minimize the intensive labor associated with various aspects of sediment-record computations...
Authors
G. F. Koltun, John R. Gray, T.J. McElhone
National water summary 1990-91: Hydrologic events and stream water quality National water summary 1990-91: Hydrologic events and stream water quality
National Water Summary 1990-91 Hydrologic Events and Stream Water Quality was planned to complement existing Federal-State water-quality reporting to the U.S. Congress that is required by the Clean Water Act of 1972. This act, formally known as the Federal Water Pollution Control Act Amendments of 1972 (Public Law 92-500), and its amendments in 1977,1979,1980,1981,1983, and 1987, is the...
Techniques for estimating flood-peak discharges of rural, unregulated streams in Ohio Techniques for estimating flood-peak discharges of rural, unregulated streams in Ohio
Multiple-regression equations are presented for estimating flood-peak discharges having recurrence intervals of 2, 5, 10, 25, 50, and 100 years at ungaged sites on rural, unregulated streams in Ohio. The average standard errors of prediction for the equations range from 33.4% to 41.4%. Peak discharge estimates determined by log-Pearson Type III analysis using data collected through the...
Authors
G. F. Koltun, J.W. Roberts
By
Science and Products
Filter Total Items: 53
Floods of June 28-29, 1998 in Ohio Floods of June 28-29, 1998 in Ohio
During a 96-hour period extending from June 26 to June 30, 1998, a stalled frontal system produced a series of storms that dumped 10 inches or more of rain on parts of Ohio. The storms occurred at the end of a relatively wet month, resulting in flooding and widespread damage throughout much of central, east-central, and southeastern Ohio. Twenty-three Ohio counties were declared Federal...
Authors
G. F. Koltun
Factors related to probability of joint flooding on paired streams in Ohio Factors related to probability of joint flooding on paired streams in Ohio
Factors related to the probability of joint flooding on paired streams were investigated. Stream pairs were considered to have flooded jointly at the design-year flood threshold (corresponding to the 2-, 10-, 25-, or 50-year instantaneous peak stream flow) if peak stream flows at both streams in the pair were observed or predicted to have equaled or exceeded the threshold on a given...
Authors
G. F. Koltun, J. M. Sherwood
Effects of hydrologic, biological, and environmental processes on sources and concentrations of fecal bacteria in the Cuyahoga River, with implications for management of recreational waters in Summit and Cuyahoga Counties, Ohio Effects of hydrologic, biological, and environmental processes on sources and concentrations of fecal bacteria in the Cuyahoga River, with implications for management of recreational waters in Summit and Cuyahoga Counties, Ohio
Discharges of fecal bacteria (fecal coliform bacteria and Escherichia coli ) to the middle main stem of the Cuyahoga River from storm water, combined sewers, and incompletely disinfected wastewater have resulted in frequent exceedances of bacteriological water-quality standards in a 23-mile reach of the river that flows through the Cuyahoga Valley National Recreation Area. Contamination...
Authors
Donna N. Myers, G. F. Koltun, Donna S. Francy
Factors related to the joint probability of flooding on paired streams Factors related to the joint probability of flooding on paired streams
The factors related to the joint probabilty of flooding on paired streams were investigated and quantified to provide information to aid in the design of hydraulic structures where the joint probabilty of flooding is an element of the design criteria. Stream pairs were considered to have flooded jointly at the design-year flood threshold (corresponding to the 2-, 10-, 25-, or 50-year...
Authors
G. F. Koltun, J. M. Sherwood
Hydrologic disturbance and response of aquatic biota in Big Darby Creek basin, Ohio Hydrologic disturbance and response of aquatic biota in Big Darby Creek basin, Ohio
Washout and recolonization of macroinvertebrates and algae associated with a spring and summer storm were measured at three sites in Ohio's Big Darby Creek Basin. Related factors, such as streamflow magnitude, shear stress, and streamed disturbance were considered when interpreting observed changes in densities and community structure of macroinvertebrates and algae. During the study...
Authors
J.A. Hambrook, G. F. Koltun, B.B. Palcsak, J.S. Tertuliani
Effects of hydrologic disturbance on washout and recolonization of stream biota Effects of hydrologic disturbance on washout and recolonization of stream biota
No abstract available
Authors
J.A. Hambrook, G. F. Koltun
Summary of floods in the United States during 1990 and 1991 Summary of floods in the United States during 1990 and 1991
This volume contains 50 articles describing severe, widespread, or unusual flooding in 28 of the 50 States during 1990 and 1991. Each flood is described to an extent commensurate with its significance and the availability of data on the hydrology and the damages. Each article includes one or more maps showing the general area of flooding. Most articles include tables of data that allow...
Authors
Paul Robert Jordan, L. J. Combs
Determination of base-flow characteristics at selected streamflow-gaging stations on the Mad River, Ohio Determination of base-flow characteristics at selected streamflow-gaging stations on the Mad River, Ohio
This report describes the results of a study to estimate characteristics of base flow and sustained ground-water discharge at five streamflow-gaging stations on the Mad River in Ohio. The five streamflow-gaging stations are located at Zanesfield, near Urbana, at St. Paris Pike (at Eagle City), near Springfield, and near Dayton. The median of the annual-mean base flows, determined by...
Authors
G. F. Koltun
User's manual for SEDCALC, a computer program for computation of suspended-sediment discharge User's manual for SEDCALC, a computer program for computation of suspended-sediment discharge
Sediment-Record Calculations (SEDCALC), a menu-driven set of interactive computer programs, was developed to facilitate computation of suspended-sediment records. The programs comprising SEDCALC were developed independently in several District offices of the U.S. Geological Survey (USGS) to minimize the intensive labor associated with various aspects of sediment-record computations...
Authors
G. F. Koltun, John R. Gray, T.J. McElhone
National water summary 1990-91: Hydrologic events and stream water quality National water summary 1990-91: Hydrologic events and stream water quality
National Water Summary 1990-91 Hydrologic Events and Stream Water Quality was planned to complement existing Federal-State water-quality reporting to the U.S. Congress that is required by the Clean Water Act of 1972. This act, formally known as the Federal Water Pollution Control Act Amendments of 1972 (Public Law 92-500), and its amendments in 1977,1979,1980,1981,1983, and 1987, is the...
Techniques for estimating flood-peak discharges of rural, unregulated streams in Ohio Techniques for estimating flood-peak discharges of rural, unregulated streams in Ohio
Multiple-regression equations are presented for estimating flood-peak discharges having recurrence intervals of 2, 5, 10, 25, 50, and 100 years at ungaged sites on rural, unregulated streams in Ohio. The average standard errors of prediction for the equations range from 33.4% to 41.4%. Peak discharge estimates determined by log-Pearson Type III analysis using data collected through the...
Authors
G. F. Koltun, J.W. Roberts
By