William H. Asquith
William has about 34 years at the USGS encompassing a wide range of algorithms and statistical and extreme value frequency studies of meteorology, surface water hydrology, and other water resources topics such as data acquisition, hydraulics, hydrologic regionalization, and research mentoring on statistical methods and algorithms.
Recent (2016–2026) research includes copula methods and algorithms; exceptionally low annual exceedance probability (AEP) flood events; regulated flood-frequency approaches; N-day volumetric flood frequency bias correction for all of US and Territories; statistics of USGS discharge measurements; technical advising on probable maximum precipitation in Texas and New Mexico-Colorado; flood- and rainfall-hazards for the Qashqadaryo Region, Uzbekistan, including defining an equal-area grid for Central Asian studies; small watershed hydrometeorological station operation; missing-record estimation; real-time uncertainty forecasting for hydrometeorological stations, and groundwater level informatics and machine-learning applications for prediction of monthly water-level grids for the Mississippi River Valley alluvial aquifer underlying the Mississippi River Alluvial Plain and Chicot aquifer, southwestern Louisiana; long-term trend analyses of daily salinity predictions for 91 monitoring locations in bays and estuaries of the gulf coast with statistical methods including Cubist, Randomforest, and Support Vector Machines; Texas lake-evaporation validation by probabilistic methods (linear moments); and reduction in USGS staffing efforts in groundwater monitoring with minimization of loss of information content from the Louisiana network.
Recent cooperators include Gulf Coast Ecosystem Restoration Council, Environment Agency – Abu Dhabi (2016−18) and Ministry of Ecology, Environmental Protection and Climate Change for the Republic of Uzbekistan (2021−26) via USGS Office of International Programs, Texas Commission on Environmental Quality, Texas Department of Transportation, Texas Water Development Board, U.S. Army Corps of Engineers, U.S. Nuclear Regulatory Commission, and USGS Office of Quality Assurance.
Thrice featured four-city speaker in 2016, 2017, and 2018 in Bolivia for Universidad Catolica Boliviana and U.S. State Department, and USGS Surfacewater Mission co-lead to Uzbekistan (June 2022, April 2024, September 2024).
Education and Certifications
Institution: Texas Tech University (TTU), College of Engineering, Lubbock, 2008–2011
Degree: Ph.D. (Civil Engineering, May 2011)Institution: University of Texas at Austin, Jackson School of Geosciences, Geoscience, 1998–2003
Degree: Ph.D. (Geosciences, May 2003)Institution: University of Texas at Austin, College of Engineering, 1988–1994
Degrees: B.S. (Civil Engineering, Dec. 1992); M.S. (Civil Engineering, May 1994)
Affiliations and Memberships*
Professional Geoscientist no. 1494, State of Texas 2003–present
Science and Products
Filter Total Items: 70
Estimation of volumetric runoff coefficients for Texas watersheds using land-use and rainfall-runoff data Estimation of volumetric runoff coefficients for Texas watersheds using land-use and rainfall-runoff data
The rational method for peak discharge (Qp) estimation was introduced in the 1880s. Although the rational method is considered simplistic, it remains an effective method for estimating peak discharge for small watersheds. The runoff coefficient (C) is a key parameter for the rational method and can be estimated in various ways. Literature-based C values (Clit) are listed for different...
Authors
Nirajan Dhakal, Xing Fang, Theodore G. Cleveland, David B. Thompson, William H. Asquith, Luke J. Marzen
Recent (2001-09) hydrologic history and regionalization studies in Texas-Statistical characterization of storms, floods, and rainfall-runoff relations Recent (2001-09) hydrologic history and regionalization studies in Texas-Statistical characterization of storms, floods, and rainfall-runoff relations
As part of numerous cooperative studies investigating rainfall and streamflow during 1991-2009 with the Texas Department of Transportation and Texas Commission on Environmental Quality, the U.S. Geological Survey (USGS) published about 20 reports describing either historical streamflow conditions (hydrologic history) in Texas or the results of studies involving regional rainfall and...
Authors
William H. Asquith
Regression equations for estimation of annual peak-streamflow frequency for undeveloped watersheds in Texas using an L-moment-based, PRESS-minimized, residual-adjusted approach Regression equations for estimation of annual peak-streamflow frequency for undeveloped watersheds in Texas using an L-moment-based, PRESS-minimized, residual-adjusted approach
Annual peak-streamflow frequency estimates are needed for flood-plain management; for objective assessment of flood risk; for cost-effective design of dams, levees, and other flood-control structures; and for design of roads, bridges, and culverts. Annual peak-streamflow frequency represents the peak streamflow for nine recurrence intervals of 2, 5, 10, 25, 50, 100, 200, 250, and 500...
Authors
William H. Asquith, Meghan C. Roussel
Regression models to estimate real-time concentrations of selected constituents in two tributaries to Lake Houston near Houston, Texas, 2005-07 Regression models to estimate real-time concentrations of selected constituents in two tributaries to Lake Houston near Houston, Texas, 2005-07
In December 2005, the U.S. Geological Survey in cooperation with the City of Houston, Texas, began collecting discrete water-quality samples for nutrients, total organic carbon, bacteria (total coliform and Escherichia coli), atrazine, and suspended sediment at two U.S. Geological Survey streamflow-gaging stations upstream from Lake Houston near Houston (08068500 Spring Creek near Spring...
Authors
Timothy D. Oden, William H. Asquith, Matthew S. Milburn
Summary of annual mean and annual harmonic mean statistics of daily mean streamflow for 620 U.S. Geological Survey streamflow-gaging stations in Texas through water year 2007 Summary of annual mean and annual harmonic mean statistics of daily mean streamflow for 620 U.S. Geological Survey streamflow-gaging stations in Texas through water year 2007
Analysts and managers of surface-water resources have interest in annual mean and annual harmonic mean statistics of daily mean streamflow for U.S. Geological Survey (USGS) streamflow-gaging stations in Texas. The mean streamflow represents streamflow volume, whereas the harmonic mean streamflow represents an appropriate statistic for assessing constituent concentrations that might...
Authors
William H. Asquith, Franklin T. Heitmuller
Evaluation of acoustic doppler velocity meters to quantify flow from Comal Springs and San Marcos Springs, Texas Evaluation of acoustic doppler velocity meters to quantify flow from Comal Springs and San Marcos Springs, Texas
Comal Springs and San Marcos Springs are the two largest springs in Texas, are major discharge points for the San Antonio segment of the Edwards aquifer, and provide habitat for several Federally listed endangered species that depend on adequate springflows for survival. It is therefore imperative that the Edwards Aquifer Authority have accurate and timely springflow data to guide...
Authors
Marcus O. Gary, Robin H. Gary, William H. Asquith
Filter Total Items: 48
Geospatial data for select U.S. Geological Survey streamflow-gaging stations in New Mexico, Oklahoma, and Texas useful for statistical study of annual peak streamflows in and near Texas Geospatial data for select U.S. Geological Survey streamflow-gaging stations in New Mexico, Oklahoma, and Texas useful for statistical study of annual peak streamflows in and near Texas
This dataset provides watershed delineations for 1,703 U.S. Geological Survey (USGS) streamgaging stations (gages) for geospatial statistical study of peak streamflows in and near Texas. These streamgaging stations are in Texas, Oklahoma, and New Mexico (east of the Great Continental Divide) with some of the watersheds associated with the 1,703 streamgaging stations extending into...
Estimated quantiles of decadal flow-duration curves using selected probability distributions fit to no-flow fractions and L-moments predicted for streamgages and for pour points of level-12 hydrologic unit codes in the southeastern United States, 1950-201 Estimated quantiles of decadal flow-duration curves using selected probability distributions fit to no-flow fractions and L-moments predicted for streamgages and for pour points of level-12 hydrologic unit codes in the southeastern United States, 1950-201
Using previously published (Robinson and others, 2019) no-flow fractions and L-moments of nonzero streamflow from decadal streamflow flow-duration analysis (daily mean streamflow), probability distributions were fit to provide 27 estimated quantiles of decadal flow-duration curves, and hence the probability distributions are a form of parametric modeling that ensures monotonicity of the...
Attributions for nonstationary peak streamflow records across the conterminous United States, 1941-2015 and 1966-2015 Attributions for nonstationary peak streamflow records across the conterminous United States, 1941-2015 and 1966-2015
The U.S. Geological Survey Dakota Water Science Center, in cooperation with the Federal Highway Administration, analyzed annual peak-flow data to determine if trends are present and provide attribution of trends where possible. Work for the national trend attributions for nonstationary annual peak-flow records was broken into seven regions that are loosely based off of two-digit...
Source code in R for creation of regional regression equations for estimation of four hydraulic properties of streams at approximate bankfull conditions for different ecoregions in Texas associated with U.S. Geological Survey Scientific Investigations Rep Source code in R for creation of regional regression equations for estimation of four hydraulic properties of streams at approximate bankfull conditions for different ecoregions in Texas associated with U.S. Geological Survey Scientific Investigations Rep
This repository contains R language source code used for creation of regional regression equations for estimation of four hydraulic properties of streams at approximate bankfull conditions for different ecoregions in Texas. This code is in support of the following study: Asquith, W.H., Gordon, J.D., and Wallace, D.S., 2020, Regional regression equations for estimation of four hydraulic...
trajPipeFlow, Discharge from horizontal and vertical flowing pipes by trajectory methods trajPipeFlow, Discharge from horizontal and vertical flowing pipes by trajectory methods
The trajPipeFlow package in the R language provides functions for computation of discharge from horizontal and vertical flowing pipes using trajectory methods of the U.S. Bureau of Reclamation Water Measurement Manual (2001, chap. 14, sec. 13).
Quality Assurance of Water Level Records from Wells in the Mississippi River Valley Alluvial Aquifer in Missouri from the Missouri Department of Natural Resource's Well Information Management System (WIMS) Quality Assurance of Water Level Records from Wells in the Mississippi River Valley Alluvial Aquifer in Missouri from the Missouri Department of Natural Resource's Well Information Management System (WIMS)
The Missouri Department of Natural Resources' (MoDNR) Well Information Management System (WIMS) is a repository for recent (1983-present) well information that includes date of completion, well construction, geology, and water level. Well information is provided by the well drillers during the permitting process and is updated regularly by MoDNR. This data set consists of well records...
Filter Total Items: 22
Science and Products
Filter Total Items: 70
Estimation of volumetric runoff coefficients for Texas watersheds using land-use and rainfall-runoff data Estimation of volumetric runoff coefficients for Texas watersheds using land-use and rainfall-runoff data
The rational method for peak discharge (Qp) estimation was introduced in the 1880s. Although the rational method is considered simplistic, it remains an effective method for estimating peak discharge for small watersheds. The runoff coefficient (C) is a key parameter for the rational method and can be estimated in various ways. Literature-based C values (Clit) are listed for different...
Authors
Nirajan Dhakal, Xing Fang, Theodore G. Cleveland, David B. Thompson, William H. Asquith, Luke J. Marzen
Recent (2001-09) hydrologic history and regionalization studies in Texas-Statistical characterization of storms, floods, and rainfall-runoff relations Recent (2001-09) hydrologic history and regionalization studies in Texas-Statistical characterization of storms, floods, and rainfall-runoff relations
As part of numerous cooperative studies investigating rainfall and streamflow during 1991-2009 with the Texas Department of Transportation and Texas Commission on Environmental Quality, the U.S. Geological Survey (USGS) published about 20 reports describing either historical streamflow conditions (hydrologic history) in Texas or the results of studies involving regional rainfall and...
Authors
William H. Asquith
Regression equations for estimation of annual peak-streamflow frequency for undeveloped watersheds in Texas using an L-moment-based, PRESS-minimized, residual-adjusted approach Regression equations for estimation of annual peak-streamflow frequency for undeveloped watersheds in Texas using an L-moment-based, PRESS-minimized, residual-adjusted approach
Annual peak-streamflow frequency estimates are needed for flood-plain management; for objective assessment of flood risk; for cost-effective design of dams, levees, and other flood-control structures; and for design of roads, bridges, and culverts. Annual peak-streamflow frequency represents the peak streamflow for nine recurrence intervals of 2, 5, 10, 25, 50, 100, 200, 250, and 500...
Authors
William H. Asquith, Meghan C. Roussel
Regression models to estimate real-time concentrations of selected constituents in two tributaries to Lake Houston near Houston, Texas, 2005-07 Regression models to estimate real-time concentrations of selected constituents in two tributaries to Lake Houston near Houston, Texas, 2005-07
In December 2005, the U.S. Geological Survey in cooperation with the City of Houston, Texas, began collecting discrete water-quality samples for nutrients, total organic carbon, bacteria (total coliform and Escherichia coli), atrazine, and suspended sediment at two U.S. Geological Survey streamflow-gaging stations upstream from Lake Houston near Houston (08068500 Spring Creek near Spring...
Authors
Timothy D. Oden, William H. Asquith, Matthew S. Milburn
Summary of annual mean and annual harmonic mean statistics of daily mean streamflow for 620 U.S. Geological Survey streamflow-gaging stations in Texas through water year 2007 Summary of annual mean and annual harmonic mean statistics of daily mean streamflow for 620 U.S. Geological Survey streamflow-gaging stations in Texas through water year 2007
Analysts and managers of surface-water resources have interest in annual mean and annual harmonic mean statistics of daily mean streamflow for U.S. Geological Survey (USGS) streamflow-gaging stations in Texas. The mean streamflow represents streamflow volume, whereas the harmonic mean streamflow represents an appropriate statistic for assessing constituent concentrations that might...
Authors
William H. Asquith, Franklin T. Heitmuller
Evaluation of acoustic doppler velocity meters to quantify flow from Comal Springs and San Marcos Springs, Texas Evaluation of acoustic doppler velocity meters to quantify flow from Comal Springs and San Marcos Springs, Texas
Comal Springs and San Marcos Springs are the two largest springs in Texas, are major discharge points for the San Antonio segment of the Edwards aquifer, and provide habitat for several Federally listed endangered species that depend on adequate springflows for survival. It is therefore imperative that the Edwards Aquifer Authority have accurate and timely springflow data to guide...
Authors
Marcus O. Gary, Robin H. Gary, William H. Asquith
Filter Total Items: 48
Geospatial data for select U.S. Geological Survey streamflow-gaging stations in New Mexico, Oklahoma, and Texas useful for statistical study of annual peak streamflows in and near Texas Geospatial data for select U.S. Geological Survey streamflow-gaging stations in New Mexico, Oklahoma, and Texas useful for statistical study of annual peak streamflows in and near Texas
This dataset provides watershed delineations for 1,703 U.S. Geological Survey (USGS) streamgaging stations (gages) for geospatial statistical study of peak streamflows in and near Texas. These streamgaging stations are in Texas, Oklahoma, and New Mexico (east of the Great Continental Divide) with some of the watersheds associated with the 1,703 streamgaging stations extending into...
Estimated quantiles of decadal flow-duration curves using selected probability distributions fit to no-flow fractions and L-moments predicted for streamgages and for pour points of level-12 hydrologic unit codes in the southeastern United States, 1950-201 Estimated quantiles of decadal flow-duration curves using selected probability distributions fit to no-flow fractions and L-moments predicted for streamgages and for pour points of level-12 hydrologic unit codes in the southeastern United States, 1950-201
Using previously published (Robinson and others, 2019) no-flow fractions and L-moments of nonzero streamflow from decadal streamflow flow-duration analysis (daily mean streamflow), probability distributions were fit to provide 27 estimated quantiles of decadal flow-duration curves, and hence the probability distributions are a form of parametric modeling that ensures monotonicity of the...
Attributions for nonstationary peak streamflow records across the conterminous United States, 1941-2015 and 1966-2015 Attributions for nonstationary peak streamflow records across the conterminous United States, 1941-2015 and 1966-2015
The U.S. Geological Survey Dakota Water Science Center, in cooperation with the Federal Highway Administration, analyzed annual peak-flow data to determine if trends are present and provide attribution of trends where possible. Work for the national trend attributions for nonstationary annual peak-flow records was broken into seven regions that are loosely based off of two-digit...
Source code in R for creation of regional regression equations for estimation of four hydraulic properties of streams at approximate bankfull conditions for different ecoregions in Texas associated with U.S. Geological Survey Scientific Investigations Rep Source code in R for creation of regional regression equations for estimation of four hydraulic properties of streams at approximate bankfull conditions for different ecoregions in Texas associated with U.S. Geological Survey Scientific Investigations Rep
This repository contains R language source code used for creation of regional regression equations for estimation of four hydraulic properties of streams at approximate bankfull conditions for different ecoregions in Texas. This code is in support of the following study: Asquith, W.H., Gordon, J.D., and Wallace, D.S., 2020, Regional regression equations for estimation of four hydraulic...
trajPipeFlow, Discharge from horizontal and vertical flowing pipes by trajectory methods trajPipeFlow, Discharge from horizontal and vertical flowing pipes by trajectory methods
The trajPipeFlow package in the R language provides functions for computation of discharge from horizontal and vertical flowing pipes using trajectory methods of the U.S. Bureau of Reclamation Water Measurement Manual (2001, chap. 14, sec. 13).
Quality Assurance of Water Level Records from Wells in the Mississippi River Valley Alluvial Aquifer in Missouri from the Missouri Department of Natural Resource's Well Information Management System (WIMS) Quality Assurance of Water Level Records from Wells in the Mississippi River Valley Alluvial Aquifer in Missouri from the Missouri Department of Natural Resource's Well Information Management System (WIMS)
The Missouri Department of Natural Resources' (MoDNR) Well Information Management System (WIMS) is a repository for recent (1983-present) well information that includes date of completion, well construction, geology, and water level. Well information is provided by the well drillers during the permitting process and is updated regularly by MoDNR. This data set consists of well records...
Filter Total Items: 22
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government