Tanja N. Williamson, PhD
Soil-water scientist experienced in natural and human-affected systems, including links with vegetation and landscape dynamics. Research interest spans landscape and water-resource effects of agriculture, mining, development, and climate change. Published research supported by OSMRE, USDA, NSF, USEPA, USGS, state agencies, and universities.
Recent and ongoing research includes:
- Hydrologic modeling of mixed land-use watersheds
- the importance of land-cover change to streamflow magnitude, variability, and seasonality
- developing decision-support systems that inform resource managers
- Incorporation of soil-physical data into hydrologic modeling
- Comparison of lab and field measurements to modeled soil properties
- Sensitivity of hydrologic models to changes in soil properties
- Simulation of hydrologic response from landscape reconstruction
- Temporal variability of soil-water storage and movement
- Agricultural resilience under projected climate change
- Delineation of ephemeral and intermittent streams in Appalachia
- Conservation management in agricultural landscapes
- Identifying sediment source
- Linking soil-water storage with the stream environment
- Extent and characteristics of tile-drains (sub-surface agricultural drainage)
Education
Ph.D. Soil and Water Science (Pedology), University of California, Riverside, 1999
M.S. Earth Science (Geomorphology), University of California, Riverside, 1995
B.S. Geoscience, The Pennsylvania State University, 1992 (includes PSU Field Camp)
Professional Experience
U.S. Geological Survey
- Research Hydrologist, Kentucky Water Science Center (2010 to present)
- Hydrologist, Kentucky Water Science Center (2006 to 2010)
Adjunct Assistant Professor, Department of Plant and Soil Sciences, University of Kentucky (2016 to present)
Quinte Conservation, Belleville, ON, Canada (2006)
Loyalist College, Belleville, ON, Canada (2004-2005)
University of the Pacific, Stockton, CA, Geosciences (1999-2004)
Science and Products
Filter Total Items: 26
Chemical and physical data for sediment source fingerprinting of suspended and bottom sediment in Black Creek, Indiana, tributary to the Maumee River and western Lake Erie - Fluvial-target samples Chemical and physical data for sediment source fingerprinting of suspended and bottom sediment in Black Creek, Indiana, tributary to the Maumee River and western Lake Erie - Fluvial-target samples
This data release includes physical and chemical data for samples from fluvial targets (streambed and suspended sediment) from three sampling sites in the Black Creek basin, Indiana. Data include total nitrogen and carbon concentrations, carbon species, total concentrations for 42 metals, and particle-size analysis. Fluvial-target samples include both soft, streambed sediment and...
Sources of Pathogens, Nutrients, and Sediment in the Upper Little River Basin, Kentucky (2012-14) Sources of Pathogens, Nutrients, and Sediment in the Upper Little River Basin, Kentucky (2012-14)
The U.S. Geological Survey (USGS), in cooperation with the Little River Water-Quality Consortium (LRWQC), collected water samples at 19 sites in the upper Little River Basin, Kentucky, from November 1, 2012 to November 30, 2014. This digital dataset contains site information, analyzing laboratories and methods, and water chemistry for these samples. Water chemistry results include...
Filter Total Items: 40
Delineation of tile-drain networks using thermal and multispectral imagery—Implications for water quantity and quality differences from paired edge-of-field sites Delineation of tile-drain networks using thermal and multispectral imagery—Implications for water quantity and quality differences from paired edge-of-field sites
As part of the Great Lakes Restoration Initiative, paired edge-of-field sites were established in high priority subwatersheds to assess the effectiveness of agricultural management practices. One pairing was in Black Creek, a tributary to the Maumee River and Lake Erie. These fields were paired because of similarity in soils, topography, and agricultural management. Following two years...
Authors
Tanja Williamson, Edward Dobrowolski, Shawn Meyer, Jeffrey Frey, Barry Allred
Multiple-source tracking: Investigating sources of pathogens, nutrients, and sediment in the Upper Little River Basin, Kentucky, water years 2013–14 Multiple-source tracking: Investigating sources of pathogens, nutrients, and sediment in the Upper Little River Basin, Kentucky, water years 2013–14
The South Fork Little River (SFLR) and the North Fork Little River (NFLR) are two major headwater tributaries that flow into the Little River just south of Hopkinsville, Kentucky. Both tributaries are included in those water bodies in Kentucky and across the Nation that have been reported with declining water quality. Each tributary has been listed by the Kentucky Energy and Environment...
Authors
Angela Crain, Mac Cherry, Tanja Williamson, Aubrey Bunch
Water quality and natural resources in the Green River Basin Water quality and natural resources in the Green River Basin
No abstract available.
Authors
Brad Lee, Tanja Williamson, Angela Crain
Sensitivity of the projected hydroclimatic environment of the Delaware River basin to formulation of potential evapotranspiration Sensitivity of the projected hydroclimatic environment of the Delaware River basin to formulation of potential evapotranspiration
The Delaware River Basin (DRB) encompasses approximately 0.4 % of the area of the United States (U.S.), but supplies water to 5 % of the population. We studied three forested tributaries to quantify the potential climate-driven change in hydrologic budget for two 25-year time periods centered on 2030 and 2060, focusing on sensitivity to the method of estimating potential...
Authors
Tanja N. Williamson, Elizabeth Nystrom, Paul C.D. Milly
Migratory bird habitat in relation to tile drainage and poorly drained hydrologic soil groups Migratory bird habitat in relation to tile drainage and poorly drained hydrologic soil groups
The Prairie Pothole Region (PPR) is home to more than 50% of the migratory waterfowl in North America. Although the PPR provides an abundance of temporary and permanent wetlands for nesting and feeding, increases in commodity prices and agricultural drainage practices have led to a trend of wetland drainage. The Northern Shoveler is a migratory dabbling duck species that uses wetland...
Authors
Brandi Kastner, Victoria Christensen, Tanja N. Williamson, Christopher Sanocki
Classification of ephemeral, intermittent, and perennial stream reaches using a TOPMODEL-based approach Classification of ephemeral, intermittent, and perennial stream reaches using a TOPMODEL-based approach
Whether a waterway is temporary or permanent influences regulatory protection guidelines, however, classification can be subjective due to a combination of factors, including time of year, antecedent moisture conditions, and previous experience of the field investigator. Our objective was to develop a standardized protocol using publicly available spatial information to classify...
Authors
Tanja N. Williamson, Carmen Agouridis, Christopher Barton, Jonathan Villines, Jeremiah Lant
Summary of hydrologic modeling for the Delaware River Basin using the Water Availability Tool for Environmental Resources (WATER) Summary of hydrologic modeling for the Delaware River Basin using the Water Availability Tool for Environmental Resources (WATER)
The Water Availability Tool for Environmental Resources (WATER) is a decision support system for the nontidal part of the Delaware River Basin that provides a consistent and objective method of simulating streamflow under historical, forecasted, and managed conditions. In order to quantify the uncertainty associated with these simulations, however, streamflow and the associated...
Authors
Tanja N. Williamson, Jeremiah Lant, Peter Claggett, Elizabeth Nystrom, Paul C.D. Milly, Hugh Nelson, Scott Hoffman, Susan Colarullo, Jeffrey M. Fischer
User manuals for the Delaware River Basin Water Availability Tool for Environmental Resources (DRB–WATER) and associated WATER application utilities User manuals for the Delaware River Basin Water Availability Tool for Environmental Resources (DRB–WATER) and associated WATER application utilities
The Water Availability Tool for Environmental Resources (WATER) is a decision support system (DSS) for the nontidal part of the Delaware River Basin (DRB) that provides a consistent and objective method of simulating streamflow under historical, forecasted, and managed conditions. WATER integrates geospatial sampling of landscape characteristics, including topographic and soil properties...
Authors
Tanja N. Williamson, Jeremiah Lant
Simulating soil-water movement through loess-veneered landscapes using nonconsilient saturated hydraulic conductivity measurements Simulating soil-water movement through loess-veneered landscapes using nonconsilient saturated hydraulic conductivity measurements
Soil Survey Geographic Database (SSURGO) data are available for the entire United States, so are incorporated in many regional and national models of hydrology and environmental management. However, SSURGO does not provide an understanding of spatial variability and only includes saturated hydraulic conductivity (Ksat) values estimated from particle size analysis (PSA). This study showed...
Authors
Tanja N. Williamson, Brad Lee, Philip Schoeneberger, W. McCauley, Samuel Indorante, Phillip Owens
Stream sediment sources in midwest agricultural basins with land retirement along channel Stream sediment sources in midwest agricultural basins with land retirement along channel
Documenting the effects of agricultural land retirement on stream-sediment sources is critical to identifying management practices that improve water quality and aquatic habitat. Particularly difficult to quantify are the effects from conservation easements that commonly are discontinuous along channelized streams and ditches throughout the agricultural midwestern United States. Our...
Authors
Tanja N. Williamson, Victoria Christensen, William Richardson, Jeffrey Frey, Allen C. Gellis, K. A. Kieta, Faith Fitzpatrick
Significance of exchanging SSURGO and STATSGO data when modeling hydrology in diverse physiographic terranes Significance of exchanging SSURGO and STATSGO data when modeling hydrology in diverse physiographic terranes
The Water Availability Tool for Environmental Resources (WATER) is a TOPMODEL-based hydrologic model that depends on spatially accurate soils data to function in diverse terranes. In Kentucky, this includes mountainous regions, karstic plateau, and alluvial plains. Soils data are critical because they quantify the space to store water, as well as how water moves through the soil to the...
Authors
Tanja N. Williamson, Charles Taylor, Jeremy Newson
Phase II modification of the Water Availability Tool for Environmental Resources (WATER) for Kentucky: The sinkhole-drainage process, point-and-click basin delineation, and results of karst test-basin simulations Phase II modification of the Water Availability Tool for Environmental Resources (WATER) for Kentucky: The sinkhole-drainage process, point-and-click basin delineation, and results of karst test-basin simulations
This report describes Phase II modifications made to the Water Availability Tool for Environmental Resources (WATER), which applies the process-based TOPMODEL approach to simulate or predict stream discharge in surface basins in the Commonwealth of Kentucky. The previous (Phase I) version of WATER did not provide a means of identifying sinkhole catchments or accounting for the effects of...
Authors
Charles Taylor, Tanja N. Williamson, Jeremy Newson, Randy Ulery, Hugh Nelson, Peter Cinotto
Non-USGS Publications**
Regolith Water in Zero-Order Chaparral and Perennial Grass Watersheds Four Decades after Vegetation Conversion Tanja N. Williamson, Brent D. Newman, Robert C. Graham, and Peter J. Shouse Vadose Zone Journal 2004 3: 3: 1007-1016 doi:10.2136/vzj2004.1007
Effects of a chaparral-to-grass conversion on soil physical and hydrologic properties after four decades Tanja N. Williamson, Robert C. Graham, and Peter J. Shouse Geoderma 2004 123: 1-2: 99-114
Pedogenesis–Terrain Links in Zero-Order Watersheds after Chaparral to Grass Vegetation Conversion Tanja N. Williamson, Paul E. Gessler, Peter J. Shouse, and Robert C. Graham Soil Science Society of America Journal 2006 70: 6: 2065-2074 doi:10.2136/sssaj2003.0316
Identification of stolen rare palm trees by soil morphological and mineralogical properties Brad D. Lee, Tanja N. Williamson, and Robert C. Graham Journal of Forensic Science 2002 47: 190-194
Forensic soils: An integrative laboratory exercise for Introductory Soil Science Brad D. Lee, Tanja N. Williamson, Robert C. Graham, and Lanny J. Lund Journal of Natural Resources and Life Sciences Education 1998 27:110-112
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Science and Products
Filter Total Items: 26
Chemical and physical data for sediment source fingerprinting of suspended and bottom sediment in Black Creek, Indiana, tributary to the Maumee River and western Lake Erie - Fluvial-target samples Chemical and physical data for sediment source fingerprinting of suspended and bottom sediment in Black Creek, Indiana, tributary to the Maumee River and western Lake Erie - Fluvial-target samples
This data release includes physical and chemical data for samples from fluvial targets (streambed and suspended sediment) from three sampling sites in the Black Creek basin, Indiana. Data include total nitrogen and carbon concentrations, carbon species, total concentrations for 42 metals, and particle-size analysis. Fluvial-target samples include both soft, streambed sediment and...
Sources of Pathogens, Nutrients, and Sediment in the Upper Little River Basin, Kentucky (2012-14) Sources of Pathogens, Nutrients, and Sediment in the Upper Little River Basin, Kentucky (2012-14)
The U.S. Geological Survey (USGS), in cooperation with the Little River Water-Quality Consortium (LRWQC), collected water samples at 19 sites in the upper Little River Basin, Kentucky, from November 1, 2012 to November 30, 2014. This digital dataset contains site information, analyzing laboratories and methods, and water chemistry for these samples. Water chemistry results include...
Filter Total Items: 40
Delineation of tile-drain networks using thermal and multispectral imagery—Implications for water quantity and quality differences from paired edge-of-field sites Delineation of tile-drain networks using thermal and multispectral imagery—Implications for water quantity and quality differences from paired edge-of-field sites
As part of the Great Lakes Restoration Initiative, paired edge-of-field sites were established in high priority subwatersheds to assess the effectiveness of agricultural management practices. One pairing was in Black Creek, a tributary to the Maumee River and Lake Erie. These fields were paired because of similarity in soils, topography, and agricultural management. Following two years...
Authors
Tanja Williamson, Edward Dobrowolski, Shawn Meyer, Jeffrey Frey, Barry Allred
Multiple-source tracking: Investigating sources of pathogens, nutrients, and sediment in the Upper Little River Basin, Kentucky, water years 2013–14 Multiple-source tracking: Investigating sources of pathogens, nutrients, and sediment in the Upper Little River Basin, Kentucky, water years 2013–14
The South Fork Little River (SFLR) and the North Fork Little River (NFLR) are two major headwater tributaries that flow into the Little River just south of Hopkinsville, Kentucky. Both tributaries are included in those water bodies in Kentucky and across the Nation that have been reported with declining water quality. Each tributary has been listed by the Kentucky Energy and Environment...
Authors
Angela Crain, Mac Cherry, Tanja Williamson, Aubrey Bunch
Water quality and natural resources in the Green River Basin Water quality and natural resources in the Green River Basin
No abstract available.
Authors
Brad Lee, Tanja Williamson, Angela Crain
Sensitivity of the projected hydroclimatic environment of the Delaware River basin to formulation of potential evapotranspiration Sensitivity of the projected hydroclimatic environment of the Delaware River basin to formulation of potential evapotranspiration
The Delaware River Basin (DRB) encompasses approximately 0.4 % of the area of the United States (U.S.), but supplies water to 5 % of the population. We studied three forested tributaries to quantify the potential climate-driven change in hydrologic budget for two 25-year time periods centered on 2030 and 2060, focusing on sensitivity to the method of estimating potential...
Authors
Tanja N. Williamson, Elizabeth Nystrom, Paul C.D. Milly
Migratory bird habitat in relation to tile drainage and poorly drained hydrologic soil groups Migratory bird habitat in relation to tile drainage and poorly drained hydrologic soil groups
The Prairie Pothole Region (PPR) is home to more than 50% of the migratory waterfowl in North America. Although the PPR provides an abundance of temporary and permanent wetlands for nesting and feeding, increases in commodity prices and agricultural drainage practices have led to a trend of wetland drainage. The Northern Shoveler is a migratory dabbling duck species that uses wetland...
Authors
Brandi Kastner, Victoria Christensen, Tanja N. Williamson, Christopher Sanocki
Classification of ephemeral, intermittent, and perennial stream reaches using a TOPMODEL-based approach Classification of ephemeral, intermittent, and perennial stream reaches using a TOPMODEL-based approach
Whether a waterway is temporary or permanent influences regulatory protection guidelines, however, classification can be subjective due to a combination of factors, including time of year, antecedent moisture conditions, and previous experience of the field investigator. Our objective was to develop a standardized protocol using publicly available spatial information to classify...
Authors
Tanja N. Williamson, Carmen Agouridis, Christopher Barton, Jonathan Villines, Jeremiah Lant
Summary of hydrologic modeling for the Delaware River Basin using the Water Availability Tool for Environmental Resources (WATER) Summary of hydrologic modeling for the Delaware River Basin using the Water Availability Tool for Environmental Resources (WATER)
The Water Availability Tool for Environmental Resources (WATER) is a decision support system for the nontidal part of the Delaware River Basin that provides a consistent and objective method of simulating streamflow under historical, forecasted, and managed conditions. In order to quantify the uncertainty associated with these simulations, however, streamflow and the associated...
Authors
Tanja N. Williamson, Jeremiah Lant, Peter Claggett, Elizabeth Nystrom, Paul C.D. Milly, Hugh Nelson, Scott Hoffman, Susan Colarullo, Jeffrey M. Fischer
User manuals for the Delaware River Basin Water Availability Tool for Environmental Resources (DRB–WATER) and associated WATER application utilities User manuals for the Delaware River Basin Water Availability Tool for Environmental Resources (DRB–WATER) and associated WATER application utilities
The Water Availability Tool for Environmental Resources (WATER) is a decision support system (DSS) for the nontidal part of the Delaware River Basin (DRB) that provides a consistent and objective method of simulating streamflow under historical, forecasted, and managed conditions. WATER integrates geospatial sampling of landscape characteristics, including topographic and soil properties...
Authors
Tanja N. Williamson, Jeremiah Lant
Simulating soil-water movement through loess-veneered landscapes using nonconsilient saturated hydraulic conductivity measurements Simulating soil-water movement through loess-veneered landscapes using nonconsilient saturated hydraulic conductivity measurements
Soil Survey Geographic Database (SSURGO) data are available for the entire United States, so are incorporated in many regional and national models of hydrology and environmental management. However, SSURGO does not provide an understanding of spatial variability and only includes saturated hydraulic conductivity (Ksat) values estimated from particle size analysis (PSA). This study showed...
Authors
Tanja N. Williamson, Brad Lee, Philip Schoeneberger, W. McCauley, Samuel Indorante, Phillip Owens
Stream sediment sources in midwest agricultural basins with land retirement along channel Stream sediment sources in midwest agricultural basins with land retirement along channel
Documenting the effects of agricultural land retirement on stream-sediment sources is critical to identifying management practices that improve water quality and aquatic habitat. Particularly difficult to quantify are the effects from conservation easements that commonly are discontinuous along channelized streams and ditches throughout the agricultural midwestern United States. Our...
Authors
Tanja N. Williamson, Victoria Christensen, William Richardson, Jeffrey Frey, Allen C. Gellis, K. A. Kieta, Faith Fitzpatrick
Significance of exchanging SSURGO and STATSGO data when modeling hydrology in diverse physiographic terranes Significance of exchanging SSURGO and STATSGO data when modeling hydrology in diverse physiographic terranes
The Water Availability Tool for Environmental Resources (WATER) is a TOPMODEL-based hydrologic model that depends on spatially accurate soils data to function in diverse terranes. In Kentucky, this includes mountainous regions, karstic plateau, and alluvial plains. Soils data are critical because they quantify the space to store water, as well as how water moves through the soil to the...
Authors
Tanja N. Williamson, Charles Taylor, Jeremy Newson
Phase II modification of the Water Availability Tool for Environmental Resources (WATER) for Kentucky: The sinkhole-drainage process, point-and-click basin delineation, and results of karst test-basin simulations Phase II modification of the Water Availability Tool for Environmental Resources (WATER) for Kentucky: The sinkhole-drainage process, point-and-click basin delineation, and results of karst test-basin simulations
This report describes Phase II modifications made to the Water Availability Tool for Environmental Resources (WATER), which applies the process-based TOPMODEL approach to simulate or predict stream discharge in surface basins in the Commonwealth of Kentucky. The previous (Phase I) version of WATER did not provide a means of identifying sinkhole catchments or accounting for the effects of...
Authors
Charles Taylor, Tanja N. Williamson, Jeremy Newson, Randy Ulery, Hugh Nelson, Peter Cinotto
Non-USGS Publications**
Regolith Water in Zero-Order Chaparral and Perennial Grass Watersheds Four Decades after Vegetation Conversion Tanja N. Williamson, Brent D. Newman, Robert C. Graham, and Peter J. Shouse Vadose Zone Journal 2004 3: 3: 1007-1016 doi:10.2136/vzj2004.1007
Effects of a chaparral-to-grass conversion on soil physical and hydrologic properties after four decades Tanja N. Williamson, Robert C. Graham, and Peter J. Shouse Geoderma 2004 123: 1-2: 99-114
Pedogenesis–Terrain Links in Zero-Order Watersheds after Chaparral to Grass Vegetation Conversion Tanja N. Williamson, Paul E. Gessler, Peter J. Shouse, and Robert C. Graham Soil Science Society of America Journal 2006 70: 6: 2065-2074 doi:10.2136/sssaj2003.0316
Identification of stolen rare palm trees by soil morphological and mineralogical properties Brad D. Lee, Tanja N. Williamson, and Robert C. Graham Journal of Forensic Science 2002 47: 190-194
Forensic soils: An integrative laboratory exercise for Introductory Soil Science Brad D. Lee, Tanja N. Williamson, Robert C. Graham, and Lanny J. Lund Journal of Natural Resources and Life Sciences Education 1998 27:110-112
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.