Ken Eng, PhD
Ken Eng is a research hydrologist in the USGS Water Resources Mission Area focusing on changes to streamflow, low flows/droughts, and environmental flows using machine learning approaches. He is based in Reston, VA.
Ken's recent work has focused on understanding and prediction of streamflow changes to unmonitored locations due to land and water management practices, such as dams, land cover, irrigation, and interbasin transfers, using machine learning approaches.
Other areas of research include work on developing regional frameworks relating environmental flow changes to aquatic biota impairment. In addition, Ken has examined the integration of subsurface/baseflow models with machine learning methods to improve predictions of low flow/drought flow characteristics.
Professional Experience
2001 to Present: Research Hydrologist, U.S. Geological Survey, Water Mission Area
Education and Certifications
Ph.D. Civil and Environmental Engineering, Cornell University, 2001
M.S. Civil and Environmental Engineering, Cornell University, 1998
B.S. Civil and Environmental Engineering, Syracuse University, 1996
Science and Products
River Corridor hot spots for biogeochemical processing: a continental scale synthesis
Rivers are the veins of the landscape, providing environmental benefits that are disproportionately high relative to their aerial extent; shedding flood waters, hosting aquatic ecosystems, transporting solutes and energy-rich materials, and storing and transforming pollutants into less harmful forms. From uplands to the coasts, rivers facilitate key biogeochemical reactions that...
Data for Modeling Interbasin Transfers of Water in Colorado and the Northeast Region, United States.
Data used to predict flow characteristics of transfers of water between hydrologic basins at the hydrologic unit code 8 (HUC8 scale) using tree-based ensemble models—random forest models for Colorado and M5 cubist models for the Northeast Region (parts of Pennsylvania, New Jersey, and New York)—are presented and documented in this data release. Interbasin transfers (IBTs) of waters are...
Data from Assessing the added value of antecedent streamflow alteration in modelling stream condition
The dataset contains long-term and short-term summaries of streamflow alteration and measures of biological condition (fish multi-metric index). Streamflow alteration metrics include the magnitude, duration, frequency, and seasonality of high and low flow streamflow. Biological condition was estimated from the National Rivers and Streams Assessment and National Water Quality Assessment...
Hydrologic metric changes across the conterminous United States
This metadata record describes the observed and estimated hydrologic metrics for the 1980 to 2019 period for U.S. Geological Survey streamgage locations across the Conterminous United States. The datasets are arranged in four files: (1) CONUS_Observed_Estimated_HMs_Annual_Monthly.csv, (2) CONUS_Bootstrap_Validations_for_Models.csv, (3) CONUS_Streamflow_Gages_for_Models.csv, and (4) Data...
Calculated baseflow recession characteristics for streamflow gauging locations for the western and eastern United States, 1900 to 2018
This metadata record describes observed and predicted baseflow recession characteristics for 300 streamflow gauges in the western United States and 282 streamflow gauges in the eastern United States. Specifically, this record describes (1) the streamflow gauge locations (west or east) in the United States (Location), (2) the U.S. Geological Survey streamflow gauge identification numbers...
Trends in selected streamflow metrics at reference streamgages in the conterminous United States, 1980-2014
This dataset includes four tables related to annual trends in streamflow metrics at 599 reference streamgages in the conterminous United States for the period 1955-2014. Reference streamgages are defined here as gages with drainage basins that are minimally impacted by anthropogenic effects such as reservoirs or urbanization. The four tables are: 1) computed annual values for 16...
Hydrologic metric changes across the conterminous United States
This metadata record describes the following eight attributes: (1) the U.S. Geological Survey streamflow gage identification number, (2) aggregated level 2 ecoregion, (3) hydrologic metric abbreviation, (4) direct-human modification classification of watershed, (5) estimated hydrologic metric values for 1950 to 2014, (6) estimated hydrologic metric values for 1980 to 2014, (7) observed...
Matched ecological assessment and stream gaging data for the CONUS
Ecological assessment data from the USGS National Water-Quality Assessment Program and the USEPA National River and Stream Assessment were reviewed and records were retained from sampling sites co-located with active USGS stream gages. A limited amount of ancillary data, including location, physical watershed features, and basic water chemistry data for each site were also retained.
Filter Total Items: 27
Streamflow characterization and hydromodification, Indian and Kill Creek Basins, Johnson County, Kansas, 1985–2018
Urban stream restoration requires a quantitative understanding of hydromodification to provide a scientific basis for establishing, prioritizing, and monitoring stream quality improvement goals. A study by the U.S. Geological Survey, in cooperation with the Johnson County Urban stream restoration benefits from a quantitative understanding of hydromodification to provide a scientific...
Authors
Teresa J. Rasmussen, Kyle E. Juracek, Patrick J. Eslick, Ken Eng, Lee J. Kellenberger
Assessing the added value of antecedent streamflow alteration information in modeling stream biological condition
In stream systems, disentangling relationships between biology and flow and subsequent prediction of these relationships to unsampled streams is a common objective of large-scale ecological modeling. Often, streamflow metrics are derived from aggregating continuous streamflow records available at a subset of stream gages into long-term flow regime descriptors. Despite demonstrated value...
Authors
Taylor E Woods, Ken Eng, Daren Carlisle, Matthew J. Cashman, Michael Meador, Karen R. Ryberg, Kelly O. Maloney
Predicting baseflow recession characteristics at ungauged stream locations using a physical and machine learning approach
Prediction of short- (i.e., aquifer is near or at saturated conditions) and long-time (i.e., aquifer is not near or at saturated conditions) baseflow recession characteristics at ungauged stream locations is a current challenge that has been primarily addressed by empirical approaches that relate these characteristics to basin attributes. However, the performance of these models is often...
Authors
Ken Eng, David M. Wolock, Michael Wieczorek
Evaluation of machine learning approaches for predicting streamflow metrics across the conterminous United States
Few regional or national scale studies have evaluated machine learning approaches for predicting streamflow metrics at ungaged locations. Most such studies are limited by the number of dimensions of the streamflow regime investigated. This study, in contrast, provides a comprehensive evaluation of the streamflow regime based on three widely available machine learning approaches (support...
Authors
Ken Eng, David M. Wolock
Severity and extent of alterations to natural streamflow regimes based on hydrologic metrics in the conterminous United States, 1980–2014
Alteration of the natural streamflow regime by land and water management, such as land-cover change and dams, is associated with aquatic ecosystem degradation. The severity and geographic extent of streamflow alteration at regional and national scales, however, remain largely unquantified. The primary goal of this study is to characterize the severity and extent of alterations to natural...
Authors
Ken Eng, Daren Carlisle, Theodore E. Grantham, David M. Wolock, Rosaly L. Eng
Flow modification in the Nation’s streams and rivers
This report summarizes a national assessment of flowing waters conducted by the U.S. Geological Survey’s (USGS) National Water-Quality Assessment (NAWQA) Project and addresses several pressing questions about the modification of natural flows in streams and rivers. The assessment is based on the integration, modeling, and synthesis of monitoring data collected by the USGS and the U.S...
Authors
Daren Carlisle, David M. Wolock, Christopher P. Konrad, Gregory J. McCabe, Ken Eng, Theodore E. Grantham, Barbara Mahler
Regional-scale associations between indicators of biological integrity and indicators of streamflow modification
Although streamflow is widely recognized as a controlling factor in stream health, empirical relations between indicators of anthropogenic modification of streamflow and ecological indicators have been elusive. The objective of this report is to build upon specific findings reported in recent publications by providing a library of empirical models that describe the relations between...
Authors
Daren Carlisle, Theodore E. Grantham, Ken Eng, David M. Wolock
Regionalization of surface-water statistics using multiple linear regression
This report serves as a reference document in support of the regionalization of surface-water statistics using multiple linear regression. Streamflow statistics are quantitative characterizations of hydrology and are often derived from observed streamflow records. In the absence of observed streamflow records, as at unmonitored or ungaged locations, other techniques are required...
Authors
William H. Farmer, Julie E. Kiang, Toby D. Feaster, Ken Eng
How hydrologic connectivity regulates water quality in river corridors
Downstream flow in rivers is repeatedly delayed by hydrologic exchange with off‐channel storage zones where biogeochemical processing occurs. We present a dimensionless metric that quantifies river connectivity as the balance between downstream flow and the exchange of water with the bed, banks, and floodplains. The degree of connectivity directly influences downstream water quality —...
Authors
Judson Harvey, Jesus Gomez-Velez, Noah Schmadel, Durelle Scott, Elizabeth W. Boyer, Richard Alexander, Ken Eng, Heather E. Golden, Albert Kettner, Christopher Konrad, Richard Moore, Jim Pizzuto, Gregory E. Schwarz, Chris Soulsby, Jay Choi
Thresholds of lake and reservoir connectivity in river networks control nitrogen removal
Lakes, reservoirs, and other ponded waters are ubiquitous features of the aquatic landscape, yet their cumulative role in nitrogen removal in large river basins is often unclear. Here we use predictive modeling, together with comprehensive river water quality, land use, and hydrography datasets, to examine and explain the influences of more than 18,000 ponded waters on nitrogen removal...
Authors
Noah M. Schmadel, Judson Harvey, Richard Alexander, Gregory E. Schwarz, Richard Moore, Ken Eng, Jesus D. Gomez-Velez, Elizabeth W. Boyer, Durelle Scott
Predictability and selection of hydrologic metrics in riverine ecohydrology
The natural flow regime is critical to the health of riverine ecosystems. Many hydrologic metrics (HMs) have been developed to describe natural flow regimes, quantify flow alteration, and provide the hydrologic foundation for the development of environmental flow standards. Many applications require the use of models to predict expected natural values of HMs from basin characteristics at...
Authors
Ken Eng, Theodore E. Grantham, Daren Carlisle, David M. Wolock
Biological relevance of streamflow metrics: Regional and national perspectives
Protecting the health of streams and rivers requires identifying ecologically significant attributes of the natural flow regime. Streamflow regimes are routinely quantified using a plethora of hydrologic metrics (HMs), most of which have unknown relevance to biological communities. At regional and national scales, we evaluated which of 509 commonly used HMs were associated with...
Authors
Daren Carlisle, Theodore E. Grantham, Ken Eng, David M. Wolock
Science and Products
River Corridor hot spots for biogeochemical processing: a continental scale synthesis
Rivers are the veins of the landscape, providing environmental benefits that are disproportionately high relative to their aerial extent; shedding flood waters, hosting aquatic ecosystems, transporting solutes and energy-rich materials, and storing and transforming pollutants into less harmful forms. From uplands to the coasts, rivers facilitate key biogeochemical reactions that...
Data for Modeling Interbasin Transfers of Water in Colorado and the Northeast Region, United States.
Data used to predict flow characteristics of transfers of water between hydrologic basins at the hydrologic unit code 8 (HUC8 scale) using tree-based ensemble models—random forest models for Colorado and M5 cubist models for the Northeast Region (parts of Pennsylvania, New Jersey, and New York)—are presented and documented in this data release. Interbasin transfers (IBTs) of waters are...
Data from Assessing the added value of antecedent streamflow alteration in modelling stream condition
The dataset contains long-term and short-term summaries of streamflow alteration and measures of biological condition (fish multi-metric index). Streamflow alteration metrics include the magnitude, duration, frequency, and seasonality of high and low flow streamflow. Biological condition was estimated from the National Rivers and Streams Assessment and National Water Quality Assessment...
Hydrologic metric changes across the conterminous United States
This metadata record describes the observed and estimated hydrologic metrics for the 1980 to 2019 period for U.S. Geological Survey streamgage locations across the Conterminous United States. The datasets are arranged in four files: (1) CONUS_Observed_Estimated_HMs_Annual_Monthly.csv, (2) CONUS_Bootstrap_Validations_for_Models.csv, (3) CONUS_Streamflow_Gages_for_Models.csv, and (4) Data...
Calculated baseflow recession characteristics for streamflow gauging locations for the western and eastern United States, 1900 to 2018
This metadata record describes observed and predicted baseflow recession characteristics for 300 streamflow gauges in the western United States and 282 streamflow gauges in the eastern United States. Specifically, this record describes (1) the streamflow gauge locations (west or east) in the United States (Location), (2) the U.S. Geological Survey streamflow gauge identification numbers...
Trends in selected streamflow metrics at reference streamgages in the conterminous United States, 1980-2014
This dataset includes four tables related to annual trends in streamflow metrics at 599 reference streamgages in the conterminous United States for the period 1955-2014. Reference streamgages are defined here as gages with drainage basins that are minimally impacted by anthropogenic effects such as reservoirs or urbanization. The four tables are: 1) computed annual values for 16...
Hydrologic metric changes across the conterminous United States
This metadata record describes the following eight attributes: (1) the U.S. Geological Survey streamflow gage identification number, (2) aggregated level 2 ecoregion, (3) hydrologic metric abbreviation, (4) direct-human modification classification of watershed, (5) estimated hydrologic metric values for 1950 to 2014, (6) estimated hydrologic metric values for 1980 to 2014, (7) observed...
Matched ecological assessment and stream gaging data for the CONUS
Ecological assessment data from the USGS National Water-Quality Assessment Program and the USEPA National River and Stream Assessment were reviewed and records were retained from sampling sites co-located with active USGS stream gages. A limited amount of ancillary data, including location, physical watershed features, and basic water chemistry data for each site were also retained.
Filter Total Items: 27
Streamflow characterization and hydromodification, Indian and Kill Creek Basins, Johnson County, Kansas, 1985–2018
Urban stream restoration requires a quantitative understanding of hydromodification to provide a scientific basis for establishing, prioritizing, and monitoring stream quality improvement goals. A study by the U.S. Geological Survey, in cooperation with the Johnson County Urban stream restoration benefits from a quantitative understanding of hydromodification to provide a scientific...
Authors
Teresa J. Rasmussen, Kyle E. Juracek, Patrick J. Eslick, Ken Eng, Lee J. Kellenberger
Assessing the added value of antecedent streamflow alteration information in modeling stream biological condition
In stream systems, disentangling relationships between biology and flow and subsequent prediction of these relationships to unsampled streams is a common objective of large-scale ecological modeling. Often, streamflow metrics are derived from aggregating continuous streamflow records available at a subset of stream gages into long-term flow regime descriptors. Despite demonstrated value...
Authors
Taylor E Woods, Ken Eng, Daren Carlisle, Matthew J. Cashman, Michael Meador, Karen R. Ryberg, Kelly O. Maloney
Predicting baseflow recession characteristics at ungauged stream locations using a physical and machine learning approach
Prediction of short- (i.e., aquifer is near or at saturated conditions) and long-time (i.e., aquifer is not near or at saturated conditions) baseflow recession characteristics at ungauged stream locations is a current challenge that has been primarily addressed by empirical approaches that relate these characteristics to basin attributes. However, the performance of these models is often...
Authors
Ken Eng, David M. Wolock, Michael Wieczorek
Evaluation of machine learning approaches for predicting streamflow metrics across the conterminous United States
Few regional or national scale studies have evaluated machine learning approaches for predicting streamflow metrics at ungaged locations. Most such studies are limited by the number of dimensions of the streamflow regime investigated. This study, in contrast, provides a comprehensive evaluation of the streamflow regime based on three widely available machine learning approaches (support...
Authors
Ken Eng, David M. Wolock
Severity and extent of alterations to natural streamflow regimes based on hydrologic metrics in the conterminous United States, 1980–2014
Alteration of the natural streamflow regime by land and water management, such as land-cover change and dams, is associated with aquatic ecosystem degradation. The severity and geographic extent of streamflow alteration at regional and national scales, however, remain largely unquantified. The primary goal of this study is to characterize the severity and extent of alterations to natural...
Authors
Ken Eng, Daren Carlisle, Theodore E. Grantham, David M. Wolock, Rosaly L. Eng
Flow modification in the Nation’s streams and rivers
This report summarizes a national assessment of flowing waters conducted by the U.S. Geological Survey’s (USGS) National Water-Quality Assessment (NAWQA) Project and addresses several pressing questions about the modification of natural flows in streams and rivers. The assessment is based on the integration, modeling, and synthesis of monitoring data collected by the USGS and the U.S...
Authors
Daren Carlisle, David M. Wolock, Christopher P. Konrad, Gregory J. McCabe, Ken Eng, Theodore E. Grantham, Barbara Mahler
Regional-scale associations between indicators of biological integrity and indicators of streamflow modification
Although streamflow is widely recognized as a controlling factor in stream health, empirical relations between indicators of anthropogenic modification of streamflow and ecological indicators have been elusive. The objective of this report is to build upon specific findings reported in recent publications by providing a library of empirical models that describe the relations between...
Authors
Daren Carlisle, Theodore E. Grantham, Ken Eng, David M. Wolock
Regionalization of surface-water statistics using multiple linear regression
This report serves as a reference document in support of the regionalization of surface-water statistics using multiple linear regression. Streamflow statistics are quantitative characterizations of hydrology and are often derived from observed streamflow records. In the absence of observed streamflow records, as at unmonitored or ungaged locations, other techniques are required...
Authors
William H. Farmer, Julie E. Kiang, Toby D. Feaster, Ken Eng
How hydrologic connectivity regulates water quality in river corridors
Downstream flow in rivers is repeatedly delayed by hydrologic exchange with off‐channel storage zones where biogeochemical processing occurs. We present a dimensionless metric that quantifies river connectivity as the balance between downstream flow and the exchange of water with the bed, banks, and floodplains. The degree of connectivity directly influences downstream water quality —...
Authors
Judson Harvey, Jesus Gomez-Velez, Noah Schmadel, Durelle Scott, Elizabeth W. Boyer, Richard Alexander, Ken Eng, Heather E. Golden, Albert Kettner, Christopher Konrad, Richard Moore, Jim Pizzuto, Gregory E. Schwarz, Chris Soulsby, Jay Choi
Thresholds of lake and reservoir connectivity in river networks control nitrogen removal
Lakes, reservoirs, and other ponded waters are ubiquitous features of the aquatic landscape, yet their cumulative role in nitrogen removal in large river basins is often unclear. Here we use predictive modeling, together with comprehensive river water quality, land use, and hydrography datasets, to examine and explain the influences of more than 18,000 ponded waters on nitrogen removal...
Authors
Noah M. Schmadel, Judson Harvey, Richard Alexander, Gregory E. Schwarz, Richard Moore, Ken Eng, Jesus D. Gomez-Velez, Elizabeth W. Boyer, Durelle Scott
Predictability and selection of hydrologic metrics in riverine ecohydrology
The natural flow regime is critical to the health of riverine ecosystems. Many hydrologic metrics (HMs) have been developed to describe natural flow regimes, quantify flow alteration, and provide the hydrologic foundation for the development of environmental flow standards. Many applications require the use of models to predict expected natural values of HMs from basin characteristics at...
Authors
Ken Eng, Theodore E. Grantham, Daren Carlisle, David M. Wolock
Biological relevance of streamflow metrics: Regional and national perspectives
Protecting the health of streams and rivers requires identifying ecologically significant attributes of the natural flow regime. Streamflow regimes are routinely quantified using a plethora of hydrologic metrics (HMs), most of which have unknown relevance to biological communities. At regional and national scales, we evaluated which of 509 commonly used HMs were associated with...
Authors
Daren Carlisle, Theodore E. Grantham, Ken Eng, David M. Wolock