Stephen Kalkhoff
Stephen Kalkhoff is currently a hydrologist with the U.S. Geological Survey, Central Midwest Water Science Center located in Iowa City, Iowa.
Steve has more than 40 years experience with the USGS in Mississippi and Iowa. While in Mississippi, his work involved documenting contamination from oil production and coastal saltwater intrusion due to industrial pumping. Steve's work in Iowa involved study of the impact of agriculture on surface and ground water in karst areas, impact of agriculture on quality of water in public supply reservoirs, impact of large-scale animal production on water quality, and impact of increased corn production for use by the ethanol industry. His studies have documented the occurrence, transport and in some case trends in nutrients, pesticides, and sediment.
Professional Experience
2015-present Project Chief of a study of spatial and temporal variability of nutrients and pesticides in an alluvial aquifer that is the source of municipal supply
2012-2014 Documented the ability of oxbow wetlands to reduce transport of nutrients from agricultural drainage tiles as Project Chief of US EPA funded project
2011-2012 Documented transport of nutrients during the record 2011 flooding in the Missouri River
2008-2009 Member of team that documented nutrient and sediment transport during record 2008 floods in Eastern Iowa
2004-2008 Project Chief - Transport of nutrients and pesticides from Iowa to the Missouri and Mississippi River study Cooperative Iowa DNR /USGS project
2004-2005 Project Chief USGS, Central Region Integrated Science program (CRISP) Perchlorate reconnaissance of surface and ground water in the United States
2000-2002 Team Member – Heinz Center Report on the State of the Nation’s water resources
1994-2012 Chief of the Eastern Iowa Basins (EIWA) study unit USGS National Water-Quality Assessment program
1986-1994 Project Chief – Big Spring project (study impact of changing land use practices on water quality in an area of karst topography in Iowa) Cooperative Iowa DNR/USGS project
1982-1986 Project Chief – Brine contamination of surface and ground water in Mississippi Cooperative Mississippi DNR/ USGS project
1985 Hydrologist – collected water samples and mapped chloride concentration gradient along Mississippi Gulf Coast to document saltwater intrusion
Education and Certifications
Graduate courses, Natural Resources, University of Minnesota,1979
B.S. Aquatic Biology--Bemidji State University, Bemidji, MN,1978
1980-1982 Hydrologist – collected water samples and prepared reports for waste assimilation studies in Mississippi
Science and Products
Occurrence and distribution of chloroacetanilide and triazine pesticide metabolites in streams in eastern Iowa
Water quality and habitat conditions in upper Midwest streams relative to riparian vegetation and soil characteristics, August 1997 : study design, methods, and data
Occurrence of acetanilide herbicide metabolites in tile runoff and ground
Degradation of chloroacetanilide herbicides: The prevalence of sulfonic and oxanilic acid metabolites in Iowa groundwaters and surface waters
Organochlorine compounds in a sediment core from Coralville reservoir, Iowa
Occurrence of selected herbicides and herbicide degradation products in Iowa's Ground Water, 1995
Relation between stream-water quality and geohydrology during base-flow conditions, Roberts creek watershed, Clayton County, Iowa
Agricultural chemicals in ground and surface water in a small watershed in Clayton County, Iowa, 1988-91
Suspended sediment and stream discharge in Bloody Run and Sny Magill watershed, water year 1992
Hydrologic data for the Big Spring basin, Clayton County, Iowa, water year 1991
National Water-Quality Assessment Program; eastern Iowa basins
Using a Geographic Information System to determine the relation between stream quality and geology in the Roberts Creek watershed, Clayton County, Iowa
Science and Products
- Science
- Data
- Publications
Filter Total Items: 71
Occurrence and distribution of chloroacetanilide and triazine pesticide metabolites in streams in eastern Iowa
No abstract available.AuthorsStephen J. Kalkhoff, E. M. ThurmanWater quality and habitat conditions in upper Midwest streams relative to riparian vegetation and soil characteristics, August 1997 : study design, methods, and data
Water-chemistry, biological, and habitat data were collected from 70 sites on Midwestern streams during August 1997 as part of an integrated, regional water-quality assessment by the U.S. Geological Survey National Water-Quality Assessment (NAWQA) Program. The study area includes the Corn Belt region of southern Minnesota, eastern Iowa, and west-central Illinois, one of the most intensive and prodAuthorsS. K. Sorenson, S. D. Porter, K.B. Akers, M.A. Harris, S. J. Kalkhoff, K. E. Lee, L. Roberts, P. J. TerrioOccurrence of acetanilide herbicide metabolites in tile runoff and ground
No abstract available.AuthorsE. M. Thurman, D.W. Kolpin, S. J. Kalkhoff, P. J. PhillipsDegradation of chloroacetanilide herbicides: The prevalence of sulfonic and oxanilic acid metabolites in Iowa groundwaters and surface waters
Water samples were collected from 88 municipal wells throughout Iowa during the summer and were collected monthly at 12 stream sites in eastern Iowa from March to December 1996 to study the occurrence of the sulfonic and oxanilic metabolites of acetochlor, alachlor, and metolachlor. The sulfonic and oxanilic metabolites were present in almost 75% of the groundwater samples and were generally preseAuthorsStephen J. Kalkhoff, Dana W. Kolpin, E. M. Thurman, I. Ferrer, D. BarceloOrganochlorine compounds in a sediment core from Coralville reservoir, Iowa
No abstract available.AuthorsS. J. Kalkhoff, Peter C. Van MetreOccurrence of selected herbicides and herbicide degradation products in Iowa's Ground Water, 1995
Herbicide compounds were prevalent in ground water across Iowa, being detected in 70% of the 106 municipal wells sampled during the summer of 1995. Herbicide degradation products were three of the four most frequently detected compounds for this study. The degradation product alachlor ethanesulfonic acid was the most frequently detected compound (65.1%), followed by atrazine (40.6%), and the degraAuthorsD.W. Kolpin, S. J. Kalkhoff, D. A. Goolsby, D. A. Sneck-Fahrer, E. M. ThurmanRelation between stream-water quality and geohydrology during base-flow conditions, Roberts creek watershed, Clayton County, Iowa
An investigation to determine the relation between stream water quality and geohydrology in the Roberts Creek watershed, Clayton County, Iowa, was conducted during selected base-flow periods in 1988-90. Discharge measurements were made and water samples collected for analyses of nutrients and selected herbicides in 19 subbasins along the main stem and tributaries of Roberts Creek. The areal extentAuthorsStephen J. KalkhoffAgricultural chemicals in ground and surface water in a small watershed in Clayton County, Iowa, 1988-91
An investigation was conducted from October 1988 through September 1991 to (1) describe the quality of water in shallow, unconsolidated materials in the 1.09-square-mile Deer Creek watershed in Clayton County, Iowa, and to (2) define the quantity and seasonal distribution of selected agricultural chemicals in water from this watershed. Surficial unconsolidated aquifer materials that discharge wateAuthorsS. J. Kalkhoff, B.D. SchaapSuspended sediment and stream discharge in Bloody Run and Sny Magill watershed, water year 1992
Hydrologic data were collected in the Bloody Run and Sny Magill watersheds in Clayton County, Iowa during the 1992 Water Year (October 1, 1991 to September 30, 1992) to provide data on suspended sediment and stream discharge from these watersheds. Suspended-sediment samples were collected daily during normal flow and several times during rainstorms. Stream stage was recorded continuously and strAuthorsStephen J. Kalkhoff, David A. EashHydrologic data for the Big Spring basin, Clayton County, Iowa, water year 1991
Hydrologic data were collected in the Big Spring Basin located in Clayton County, Iowa, during the 1991 water year. The data were collected by the U.S. Geological Survey in cooperation with the Iowa Department of Natural Resources, Geological Survey Bureau, to provide information on variation and movement of agricultural chemicals in the hydrologic cycle in the basin. Precipitation, surface-water,AuthorsS. J. Kalkhoff, R.L. KuzniarNational Water-Quality Assessment Program; eastern Iowa basins
No abstract available.AuthorsStephen J. KalkhoffUsing a Geographic Information System to determine the relation between stream quality and geology in the Roberts Creek watershed, Clayton County, Iowa
A geographic information system (GIS) was used to determine the relation between the stream-water quality and underlying geology in Roberts Creek watershed, Clayton County, Iowa, for base-flow conditions during the spring and summer of 1988–90. Geologic, stream, basin and subbasin boundaries, and water-quality sampling-site coverages were created by digitizing available maps. A contour coverage waAuthorsStephen J. Kalkhoff