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
Morphological Analyses and Simulated Flood Elevations in a Watershed with Dredged and Leveed Stream Channels, Wheeling Creek, Eastern Ohio Morphological Analyses and Simulated Flood Elevations in a Watershed with Dredged and Leveed Stream Channels, Wheeling Creek, Eastern Ohio
The USGS, in cooperation with the Ohio Emergency Management Agency, conducted a study in the Wheeling Creek Basin to (1) evaluate and contrast land-cover characteristics from 2001 with characteristics from 1979 and 1992; (2) compare current streambed elevation, slope, and geometry with conditions present in the late 1980s; (3) look for evidence of channel filling and over widening in...
Authors
James M. Sherwood, Carrie A. Huitger, Andrew D. Ebner, G. F. Koltun
Flood of June 22-24, 2006, in North-Central Ohio, With Emphasis on the Cuyahoga River Near Independence Flood of June 22-24, 2006, in North-Central Ohio, With Emphasis on the Cuyahoga River Near Independence
Heavy rains caused severe flooding on June 22-24, 2006, and damaged approximately 4,580 homes and 48 businesses in Cuyahoga County. Damage estimates in Cuyahoga County for the two days of flooding exceed $47 million; statewide damage estimates exceed $150 million. Six counties (Cuyahoga, Erie, Huron, Lucas, Sandusky, and Stark) in northeast Ohio were declared Federal disaster areas. One...
Authors
James M. Sherwood, Andrew D. Ebner, G. F. Koltun, Brian M. Astifan
User's manual for the Graphical Constituent Loading Analysis System (GCLAS) User's manual for the Graphical Constituent Loading Analysis System (GCLAS)
This manual describes the Graphical Constituent Loading Analysis System (GCLAS), an interactive cross-platform program for computing the mass (load) and average concentration of a constituent that is transported in stream water over a period of time. GCLAS computes loads as a function of an equal-interval streamflow time series and an equal- or unequal-interval time series of constituent
Authors
G. F. Koltun, Michael Eberle, J. R. Gray, G.D. Glysson
Velocity, bathymetry, and transverse mixing characteristics of the Ohio River upstream from Cincinnati, Ohio, October 2004–March 2006 Velocity, bathymetry, and transverse mixing characteristics of the Ohio River upstream from Cincinnati, Ohio, October 2004–March 2006
Velocity, bathymetry, and transverse (cross-channel) mixing characteristics were studied in a 34-mile study reach of the Ohio River extending from the lower pool of the Captain Anthony Meldahl Lock and Dam, near Willow Grove, Ky, to just downstream from the confluence of the Licking and Ohio Rivers, near Newport, Ky. Information gathered in this study ultimately will be used to...
Authors
G. F. Koltun, Chad J. Ostheimer, Michael S. Griffin
A Streamflow Statistics (StreamStats) Web Application for Ohio A Streamflow Statistics (StreamStats) Web Application for Ohio
A StreamStats Web application was developed for Ohio that implements equations for estimating a variety of streamflow statistics including the 2-, 5-, 10-, 25-, 50-, 100-, and 500-year peak streamflows, mean annual streamflow, mean monthly streamflows, harmonic mean streamflow, and 25th-, 50th-, and 75th-percentile streamflows. StreamStats is a Web-based geographic information system...
Authors
G. F. Koltun, Stephanie P. Kula, Barry M. Puskas
Upper Auglaize watershed AGNPS modeling project Upper Auglaize watershed AGNPS modeling project
The Upper Auglaize Watershed agricultural non-point source modeling project was an interagency effort to use a Geographic Information System (GIS)-based modeling approach for assessing and reducing pollution from agricultural runoff and other non-point sources. This project applied the U.S. Department of Agriculture (USDA), Agricultural Research Service’s AGricultural Non-Point Source...
Authors
Ronald L. Bingner, Kevin Czajkowski, Michael Palmer, James Coss, Steve Davis, Jim Stafford, Norm Wideman, Fred D. Theurer, G. F. Koltun, Pete Richards, Tony Friona
Science and Products
Filter Total Items: 53
Morphological Analyses and Simulated Flood Elevations in a Watershed with Dredged and Leveed Stream Channels, Wheeling Creek, Eastern Ohio Morphological Analyses and Simulated Flood Elevations in a Watershed with Dredged and Leveed Stream Channels, Wheeling Creek, Eastern Ohio
The USGS, in cooperation with the Ohio Emergency Management Agency, conducted a study in the Wheeling Creek Basin to (1) evaluate and contrast land-cover characteristics from 2001 with characteristics from 1979 and 1992; (2) compare current streambed elevation, slope, and geometry with conditions present in the late 1980s; (3) look for evidence of channel filling and over widening in...
Authors
James M. Sherwood, Carrie A. Huitger, Andrew D. Ebner, G. F. Koltun
Flood of June 22-24, 2006, in North-Central Ohio, With Emphasis on the Cuyahoga River Near Independence Flood of June 22-24, 2006, in North-Central Ohio, With Emphasis on the Cuyahoga River Near Independence
Heavy rains caused severe flooding on June 22-24, 2006, and damaged approximately 4,580 homes and 48 businesses in Cuyahoga County. Damage estimates in Cuyahoga County for the two days of flooding exceed $47 million; statewide damage estimates exceed $150 million. Six counties (Cuyahoga, Erie, Huron, Lucas, Sandusky, and Stark) in northeast Ohio were declared Federal disaster areas. One...
Authors
James M. Sherwood, Andrew D. Ebner, G. F. Koltun, Brian M. Astifan
User's manual for the Graphical Constituent Loading Analysis System (GCLAS) User's manual for the Graphical Constituent Loading Analysis System (GCLAS)
This manual describes the Graphical Constituent Loading Analysis System (GCLAS), an interactive cross-platform program for computing the mass (load) and average concentration of a constituent that is transported in stream water over a period of time. GCLAS computes loads as a function of an equal-interval streamflow time series and an equal- or unequal-interval time series of constituent
Authors
G. F. Koltun, Michael Eberle, J. R. Gray, G.D. Glysson
Velocity, bathymetry, and transverse mixing characteristics of the Ohio River upstream from Cincinnati, Ohio, October 2004–March 2006 Velocity, bathymetry, and transverse mixing characteristics of the Ohio River upstream from Cincinnati, Ohio, October 2004–March 2006
Velocity, bathymetry, and transverse (cross-channel) mixing characteristics were studied in a 34-mile study reach of the Ohio River extending from the lower pool of the Captain Anthony Meldahl Lock and Dam, near Willow Grove, Ky, to just downstream from the confluence of the Licking and Ohio Rivers, near Newport, Ky. Information gathered in this study ultimately will be used to...
Authors
G. F. Koltun, Chad J. Ostheimer, Michael S. Griffin
A Streamflow Statistics (StreamStats) Web Application for Ohio A Streamflow Statistics (StreamStats) Web Application for Ohio
A StreamStats Web application was developed for Ohio that implements equations for estimating a variety of streamflow statistics including the 2-, 5-, 10-, 25-, 50-, 100-, and 500-year peak streamflows, mean annual streamflow, mean monthly streamflows, harmonic mean streamflow, and 25th-, 50th-, and 75th-percentile streamflows. StreamStats is a Web-based geographic information system...
Authors
G. F. Koltun, Stephanie P. Kula, Barry M. Puskas
Upper Auglaize watershed AGNPS modeling project Upper Auglaize watershed AGNPS modeling project
The Upper Auglaize Watershed agricultural non-point source modeling project was an interagency effort to use a Geographic Information System (GIS)-based modeling approach for assessing and reducing pollution from agricultural runoff and other non-point sources. This project applied the U.S. Department of Agriculture (USDA), Agricultural Research Service’s AGricultural Non-Point Source...
Authors
Ronald L. Bingner, Kevin Czajkowski, Michael Palmer, James Coss, Steve Davis, Jim Stafford, Norm Wideman, Fred D. Theurer, G. F. Koltun, Pete Richards, Tony Friona