William H Asquith
William has more than 25 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, and hydrologic regionalization.
Biography
Present (2016–2018) research includes exceptionally low annual exceedance probability (AEP) flood events, regulated flood-frequency, documentable climate-cycle impacts on flood-risk assessment, statistics of USGS discharge measurements, recent technical advisor on probable maximum precipitation in Texas, small watershed hydrometeorological stations, and missing record estimation. Recent cooperators include Environment Agency – Abu Dhabi via USGS Office of International Programs, Texas Commission on Environmental Quality, Texas Department of Transportation, U.S. Army Corps of Engineers, U.S. Nuclear Regulatory Commission, and USGS Office of Surface Water. Twice featured four-city speaker in 2016 and 2017 in Bolivia for Universidad Catolica Boliviana and U.S. State Department.
EDUCATION AND CERTIFICATION:
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)
Professional Geoscientist no. 1494, State of Texas 2003–present
Science and Products
Modeling and Projecting the Influence of Climate Change on Texas Surface Waters and their Aquatic Biotic Communities
Water scarcity is a growing concern in Texas, where surface water is derived almost entirely from rainfall. Changes in air temperature and precipitation patterns associated with global climate change are anticipated to regionally affect the quality and quantity of inland surface waters and consequently their suitability as habitat for freshwater life. In addition to directly affecting resident...
Prediction and inference of flow-duration curves using multi-output neural networks
We develop multi-output neural network models (MNNs) to predict flow-duration curves (FDCs) in 9,203 ungaged locations in the Southeastern United States for six decades between 1950-2009. The model architecture contains multiple response variables in the output layer that correspond to individual quantiles along the FDC. During training,...
Worland, Scott C.; Steinschneider, Scott; Asquith, William H.; Knight, Rodney; Wieczorek, Michael
Potentiometric surface of the Mississippi River Valley alluvial aquifer, spring 2016
A potentiometric surface map for spring 2016 was created for the Mississippi River Valley alluvial (MRVA) aquifer using selected available groundwater-altitude data from wells and surface-water-altitude data from streamgages. Most of the wells were measured annually or one time after installation, but some wells were measured more than one time or...
McGuire, Virginia L.; Seanor, Ronald C.; Asquith, William H.; Kress, Wade H.; Strauch, Kellan R. Characterizing groundwater/surface-water interaction using hydrograph-separation techniques and groundwater-level data throughout the Mississippi Delta, USA
The Mississippi Delta, located in northwest Mississippi, is an area dense with industrial-level agriculture sustained by groundwater-dependent irrigation supplied by the Mississippi River Valley Alluvial aquifer (alluvial aquifer). The Delta provides agricultural commodities across the United States and around the world. Observed declines in...
Killian, Courtney D.; Asquith, William H.; Barlow, Jeannie R. B.; Bent, Gardner C.; Kress, Wade H.; Barlow, Paul M.; Schmitz, Darrel W.
Annual and approximately quarterly series peak streamflow derived from interpretations of indirect measurements for a crest-stage gage network in Texas through water year 2015
In 2006, the U.S. Geological Survey (USGS), incooperation with the Texas Department of Transportation,began collecting annual and approximately quarterly seriespeak-streamflow data at streamflow-gaging stations in smalltomedium-sized watersheds in central and western Texasas part of a crest-stage gage (CSG) network, along withselected flood-...
Asquith, William H.; Harwell, Glenn R.; Winters, Karl E.
Application of at-site peak-streamflow frequency analyses for very low annual exceedance probabilities
The U.S. Geological Survey (USGS), in cooperation with the U.S. Nuclear Regulatory Commission, has investigated statistical methods for probabilistic flood hazard assessment to provide guidance on very low annual exceedance probability (AEP) estimation of peak-streamflow frequency and the quantification of corresponding uncertainties using...
Asquith, William H.; Kiang, Julie E.; Cohn, Timothy A.
Refining previous estimates of groundwater outflows from the Medina/Diversion Lake system, San Antonio area, Texas
IntroductionIn 2016, the U.S. Geological Survey (USGS), in cooperation with the San Antonio Water System, began a study to refine previously derived estimates of groundwater outflows from Medina and Diversion Lakes in south-central Texas near San Antonio. When full, Medina and Diversion Lakes (hereinafter referred to as the Medina/Diversion Lake...
Slattery, Richard N.; Asquith, William H.; Gordon, John D. Long-term trend analysis of reservoir water quality and quantity at the landscape scale in two major river basins of Texas, USA.
Trends in water quality and quantity were assessed for 11 major reservoirs of the Brazos and Colorado river basins in the southern Great Plains (maximum period of record, 1965–2010). Water quality, major contributing-stream inflow, storage, local precipitation, and basin-wide total water withdrawals were analyzed. Inflow and storage...
Patino, Reynaldo; Asquith, William H.; VanLandeghem, Matthew M.; Dawson, D. Lithologic and hydrologic controls of mixed alluvial-bedrock channels in flood-prone fluvial systems: bankfull and macrochannels in the Llano River watershed, central Texas, USA
The rural and unregulated Llano River watershed located in central Texas, USA, has a highly variable flow regime and a wide range of instantaneous peak flows. Abrupt transitions in surface lithology exist along the main-stem channel course. Both of these characteristics afford an opportunity to examine hydrologic, lithologic, and sedimentary...
Heitmuller, Frank T.; Hudson, Paul F.; Asquith, William H.
Trend analysis and selected summary statistics of annual mean streamflow for 38 selected long-term U.S. Geological Survey streamgages in Texas, water years 1916-2012
In 2013, the U.S. Geological Survey (USGS) operated more than 500 continuous streamgages (streamflow-gaging stations) in Texas. In cooperation with the Texas Water Development Board, the USGS evaluated mean annual streamflow data for 38 selected streamgages that were active as of water year 2012. The 38 streamgages have annual mean streamflow data...
Asquith, William H.; Barbie, Dana L.
Linkage of the Soil and Water Assessment Tool and the Texas Water Availability Model to simulate the effects of brush management on monthly storage of Canyon Lake, south-central Texas, 1995-2010
The U.S. Geological Survey (USGS), in cooperation with the Texas State Soil and Water Conservation Board, developed and applied an approach to create a linkage between the published upper Guadalupe River Soil Water Assessment Tool (SWAT) brush-management (ashe juniper [Juniperus ashei]) model and the full authorization version Guadalupe River...
Asquith, William H.; Bumgarner, Johnathan R. Parameter estimation for the 4-parameter Asymmetric Exponential Power distribution by the method of L-moments using R
The implementation characteristics of two method of L-moments (MLM) algorithms for parameter estimation of the 4-parameter Asymmetric Exponential Power (AEP4) distribution are studied using the R environment for statistical computing. The objective is to validate the algorithms for general application of the AEP4 using R. An algorithm was...
Asquith, William H. Regression models of discharge and mean velocity associated with near-median streamflow conditions in Texas: utility of the U.S. Geological Survey discharge measurement database
A database containing more than 16,300 discharge values and ancillary hydraulic attributes was assembled from summaries of discharge measurement records for 391 USGS streamflow-gauging stations (streamgauges) in Texas. Each discharge is between the 40th- and 60th-percentile daily mean streamflow as determined by period-of-record, streamgauge-...
Asquith, William H.