Wesley Henson is a Research Hydrologist in San Diego, California. His research focuses on developing decision tools and methods to improve water management for food and water security and water resource sustainability.
Wes grew up in the dusty parched deserts of northern Nevada. He holds degrees in Geology, Hydrogeology, and Agricultural and Biological Engineering. He began his career with the USGS in 2009 and currently leads a Food and Water Security Research Team. His team helps address critical water resource issues, both nationally and internationally. Much of his current work is centered in a key US agricultural region—the Central Coast of California.
His research centers on incorporating additional hydrologic processes in hydrologic models so they are more suitable to address a wide variety of the challenges water managers must address. These methods include:
- Methods for estimating recharge, runoff, and land use.
- Quantifying regional scale uncertainty in water budgets (e.g., Sea Water Intrusion)
- Evaluating aquifer vulnerability to contaminants
- Nitrate biogeochemistry, and
- Development and simulation of karst aquifer preferential flow paths.
Science and Products
Salinas Valley Operational Model: Interlake Tunnel and San Antonio Spillway Modification Project
Salinas and Carmel Rivers Basin Study: Paso Robles Model Update
Salinas and Carmel River Basins Study
SGMApy: An open source platform for computing sustainability metrics and visualizing MODFLOW data
Pajaro Valley Hydrologic Model Update, Data Collection, and Analysis for Sustainability
Simulation of Water Resources Management in the Pajaro Valley
Monthly crop irrigation withdrawals and efficiencies by HUC12 watershed for years 2000-2020 within the conterminous United States
Irrigation water use reanalysis for the 2000-20 period by HUC12, month, and year for the conterminous United States
Lower Salinas Valley Hydrologic Models: Agricultural and Municipal Water Supply and Groundwater Data
Lower Salinas Valley Hydrologic Models: Climate Data
Salinas Valley Hydrologic System: Regional Climate Data
Salinas Valley Operational Model: Input Operational Data (ver. 2.0, September 2023)
Lower Salinas Valley Hydrologic Models: Discretization Data (ver. 1.1, July 2023)
Salinas Valley Hydrologic Models: Surface Water Data
Estimated monthly water use for irrigation by 12-digit hydrologic unit in the conterminous United States for 2015
Detection and measurement of land-surface deformation, Pajaro Valley, Santa Cruz and Monterey counties, California, 2015–18
Rio Grande transboundary integrated hydrologic model and water-availability analysis, New Mexico and Texas, United States, and northern Chihuahua, Mexico
One-Water Hydrologic Flow Model: A MODFLOW based conjunctive-use simulation software
Integrated hydrologic modeling of the Salinas River, California, for sustainable water management
Spatially distributed denitrification in a karst springshed
UZIG research: Measurement and characterization of unsaturated zone processes under wide-ranging climates and changing conditions
What makes a first‐magnitude spring?: Global sensitivity analysis of a speleogenesis model to gain insight into karst network and spring genesis
Input data processing tools for the integrated hydrologic model GSFLOW
Rio Grande transboundary integrated hydrologic model and water-availability analysis, New Mexico and Texas, United States, and Northern Chihuahua, Mexico
Errata**September 28, 2018: The purpose of a USGS Open-file report (OFR) is dissemination of information that must be released immediately to fill a public need or information that is not sufficiently refined to warrant publication in one of the other USGS series. As part of that refinement process, an error was discovered in one of the input data sets of the Rio Grande Transboundary Integrated Hy
Nitrate reduction mechanisms and rates in an unconfined eogenetic karst aquifer in two sites with different redox potential
CRT--Cascade Routing Tool to define and visualize flow paths for grid-based watershed models
CalPUR-LUE
CRT: Cascade Routing Tool to Define and Visualize Flow Paths for Grid-Based Watershed Models
The U.S. Geological Survey Cascade Routing Tool (CRT) is a computer application for watershed models that include the coupled Groundwater and Surface-water FLOW model GSFLOW and the Precipitation-Runoff Modeling System (PRMS). CRT generates output to define cascading surface and shallow subsurface flow paths for grid-based model domains.
MODPATH Observation Process (MODPATH-OBS)
The MODPATH-OBS (Hanson and others, 2013) computer program is designed to calculate simulated equivalents for observations related to advective groundwater transport that can be represented in a quantitative way by using simulated particle-tracking data.
Science and Products
- Science
Salinas Valley Operational Model: Interlake Tunnel and San Antonio Spillway Modification Project
An operational model for Salinas Valley is needed to evaluate and compare ecosystem, conservation, and water demands. This model must simulate current operations, assess benefits of and evaluate scenarios for tunnel operation and potential reservoir and spillway modifications.Salinas and Carmel Rivers Basin Study: Paso Robles Model Update
The existing Paso Robles Basin Model (PRBM) needed to be updated and enhanced to achieve the timeline and objectives of the Salinas Carmel River Basin Study (SCRBS) for the U.S. Bureau of Reclamation (Reclamation) and local partners.Salinas and Carmel River Basins Study
Together, the Salinas and Carmel river basins include some of the world’s most fertile agricultural lands and are internationally known for their natural beauty; ecological diversity; multi-national cultural history; and recreation opportunities such as fishing, auto racing, and golfing. The area is oftentimes referred to as the “Salad Bowl of the World” or “America’s Salad Bowl” because of the...SGMApy: An open source platform for computing sustainability metrics and visualizing MODFLOW data
Climate change and demographic changes have underscored the need to improve effectiveness of managing valuable water resources for sustainability. In 2014, the Sustainable Groundwater Management Act (SGMA) established a framework for sustainable, local groundwater management. SGMA requires groundwater-dependent regions to halt overdraft and bring basins into balanced levels of pumping and recharge...Pajaro Valley Hydrologic Model Update, Data Collection, and Analysis for Sustainability
The Pajaro Valley is home to a billion-dollar agricultural industry, providing food and food processing services for the nation. The water for these enterprises is supplied, in large part, by the groundwater resources (aquifers) in the area. The Pajaro Valley Water Management Agency (PV Water) and the USGS have partnered to improve aquifer monitoring software, allowing better quantification and...Simulation of Water Resources Management in the Pajaro Valley
Two key hydrologic issues in all coastal aquifer systems are the delineation and the management of the renewable water resources. The proper development and management of the renewable resources helps to minimize ground-water mining of the lower aquifer systems, and minimizes overdraft and seawater intrusion of the upper aquifer system while maximizing the sustainable yield of the renewable water... - Data
Monthly crop irrigation withdrawals and efficiencies by HUC12 watershed for years 2000-2020 within the conterminous United States
The USGS has published United States water-use data every five years since 1950. To increase the temporal and spatial availability of water use estimates using nationally consistent methods, the USGS is developing national water-use models for each major water-use category. This data release publishes crop irrigation withdrawals for the conterminous United States (CONUS) that are calculated usingIrrigation water use reanalysis for the 2000-20 period by HUC12, month, and year for the conterminous United States
This data release provides a monthly irrigation water use reanalysis for the period 2000-20 for all USGS Watershed Boundary Dataset of Subwatersheds (HUC12) in the conterminous United States (CONUS). Results include reference evapotranspiration (ETo), actual evapotranspiration (ETa), irrigated areas, consumptive use, and effective precipitation for each HUC12. ETo and ETa were estimated using theLower Salinas Valley Hydrologic Models: Agricultural and Municipal Water Supply and Groundwater Data
This digital dataset contains the surface water operational data used for the Salinas Valley Operational Model (SVOM) including the time series data and the operational rules. While much of the input data is shared between the Salinas Valley Operational Model (SVOM) and the Salinas Valley Integrated Hydrologic Model (SVIHM), the SVOM has additional input data specific to the purpose and function oLower Salinas Valley Hydrologic Models: Climate Data
This digital dataset contains the climate data used for the Lower Salinas Valley Hydrologic Models (Salinas Valley Integrated Hydrologic Model (SVIHM) and Salinas Valley Operational Model (SVOM)). The monthly climate data for the Lower Salinas Valley Hydrologic Models are based on the regional climate data for the Salinas Valley Hydrologic System [Hevesi and others, 2022]. To develop the monthly cSalinas Valley Hydrologic System: Regional Climate Data
This digital dataset contains the climate data used for the Salinas Valley Hydrologic System, including the Salinas Valley Watershed Model (SVWM) and the Lower Salinas Valley Hydrologic Models (Salinas Valley Integrated Hydrologic Model (SVIHM) and Salinas Valley Operational Model (SVOM)). The climate data include spatially distributed daily precipitation, maximum and minimum air temperature, andSalinas Valley Operational Model: Input Operational Data (ver. 2.0, September 2023)
This digital dataset contains the surface water operational data used for the Salinas Valley Operational Model (SVOM) including the timeseries data and the operational rules. While much of the input data is shared between the Salinas Valley Operational Model (SVOM) and the Salinas Valley Integrated Hydrologic Model (SVIHM), the SVOM has additional input data specific to the purpose and function ofLower Salinas Valley Hydrologic Models: Discretization Data (ver. 1.1, July 2023)
The Lower Salinas Valley Hydrologic Models’ discretization data includes a shapefile of the model domain and layers and a shapefile of the water balance subregions. The Lower Salinas Valley Hydrologic Models include a historical model, the Salinas Valley Integrated Hydrologic Model (SVIHM) and a reservoir operations model, the Salinas Valley Operational Model (SVOM). While the Lower Salinas ValleySalinas Valley Hydrologic Models: Surface Water Data
This digital dataset contains the surface water data used for both the Salinas Valley Watershed Model (SVWM) and the Lower Salinas Valley Hydrologic Models (Salinas Valley Integrated Hydrologic Model (SVIHM) and Salinas Valley Operational Model (SVOM)). The surface water dataset includes describes two regions of the Salinas River Watershed; the upper region is occurs primarily within San Luis ObisEstimated monthly water use for irrigation by 12-digit hydrologic unit in the conterminous United States for 2015
This data release contains the output of the Irrigation Water Use Estimation Disaggregation and Downscaling Model (IWUEDD) along with the scripts and data resources (IWUEDD_basic.zip) required to replicate the output results. The IWUEDD is used to estimate monthly irrigation withdrawals and consumptive use for each 12-digit hydrologic unit code (HUC 12) subwatershed in the conterminous United Stat - Publications
Detection and measurement of land-surface deformation, Pajaro Valley, Santa Cruz and Monterey counties, California, 2015–18
Land-surface deformation (subsidence) caused by groundwater withdrawal is identified as an undesirable result in the Pajaro Valley Water Management Agency’s Basin Management Plan and California’s Sustainable Groundwater Management Act. In Pajaro Valley, groundwater provides nearly 90 percent of the total water supply. To aid the development of sustainable groundwater management criteria, the U.S.AuthorsJustin T. Brandt, Marisa M. Earll, Michelle Sneed, Wesley R. HensonRio Grande transboundary integrated hydrologic model and water-availability analysis, New Mexico and Texas, United States, and northern Chihuahua, Mexico
Changes in population, agricultural development and practices (including shifts to more water-intensive crops), and climate variability are increasing demands on available water resources, particularly groundwater, in one of the most productive agricultural regions in the Southwest—the Rincon and Mesilla Valley parts of Rio Grande Valley, Doña Ana and Sierra Counties, New Mexico, and El Paso CountAuthorsRandall T. Hanson, Andre B. Ritchie, Scott E. Boyce, Amy E. Galanter, Ian A. Ferguson, Lorraine E. Flint, Alan L. Flint, Wesley R. HensonOne-Water Hydrologic Flow Model: A MODFLOW based conjunctive-use simulation software
The U.S. Geological Survey’s (USGS) Modular Ground-Water Flow Model (MODFLOW-2005) is a computer program that simulates groundwater flow by using finite differences. The MODFLOW-2005 framework uses a modular design that allows for the easy development and incorporation of new features called processes and packages that work with or modify inputs to the groundwater-flow equation. A process solves aAuthorsScott E. Boyce, Randall T. Hanson, Ian Ferguson, Wolfgang Schmid, Wesley R. Henson, Thomas Reimann, Steffen W. Mehl, Marisa M. EarllIntegrated hydrologic modeling of the Salinas River, California, for sustainable water management
The Salinas River is the largest river in California’s Central Coast region. Groundwater resources of the Salinas River basin are used to meet water supply needs, including crop irrigation and municipal water supply. Two large multipurpose reservoirs also supply irrigation and municipal water uses. Historical imbalances between supply and demand have resulted in sinking groundwater levels, seawateAuthorsJoseph A. Hevesi, Wesley R. Henson, Randall T. Hanson, Scott E. BoyceSpatially distributed denitrification in a karst springshed
Karst spring measurements assess biogeochemical processes occurring within groundwater contributing areas to springs (springsheds) but can only provide aggregated information. To better understand spatially distributed processes that comprise these aggregated measures, we investigated aquifer denitrification evidence in groundwater wells (n = 16) distributed throughout a springshed in the Upper FlAuthorsWesley R. Henson, Matthew J. Cohen, Wendy D. GrahamUZIG research: Measurement and characterization of unsaturated zone processes under wide-ranging climates and changing conditions
Unsaturated zone properties and processes are central to understanding the interacting effects of land-use change, contamination, and hydroclimate on our ability to grow food, sustain clean water supplies, and minimize loss of life and property. Advances in unsaturated zone science are being achieved through collaborations across traditional boundaries where information from biological, physical,AuthorsJared J. Trost, Benjamin B. Mirus, Kimberlie Perkins, Wesley R. Henson, John R. Nimmo, Rafael Munoz-CarpenaWhat makes a first‐magnitude spring?: Global sensitivity analysis of a speleogenesis model to gain insight into karst network and spring genesis
Often, karstic conduit network geometry is unknown. This lack of knowledge represents a significant limitation when modeling flow and solute transport in karst systems. In this study, we apply Morris Method Global Sensitivity Analysis to a speleogenesis model to identify model input parameters, and combinations thereof, that most significantly influence evolution of karst conduit networks, developAuthorsWesley R. Henson, Rob de Rooij, Wendy D. GrahamInput data processing tools for the integrated hydrologic model GSFLOW
Integrated hydrologic modeling (IHM) encompasses a vast number of processes and specifications, variable in time and space, and development of models can be arduous. Model input construction techniques have not been formalized or made easily reproducible. Creating the input files for integrated hydrologic models requires complex GIS processing of raster and vector datasets from various sources. DeAuthorsMurphy A. Gardner, Charles G. Morton, Justin L. Huntington, Richard G. Niswonger, Wesley R. HensonRio Grande transboundary integrated hydrologic model and water-availability analysis, New Mexico and Texas, United States, and Northern Chihuahua, Mexico
Errata**September 28, 2018: The purpose of a USGS Open-file report (OFR) is dissemination of information that must be released immediately to fill a public need or information that is not sufficiently refined to warrant publication in one of the other USGS series. As part of that refinement process, an error was discovered in one of the input data sets of the Rio Grande Transboundary Integrated Hy
AuthorsRandall T. Hanson, Andre B. Ritchie, Scott E. Boyce, Ian Ferguson, Amy E. Galanter, Lorraine E. Flint, Wesley R. HensonNitrate reduction mechanisms and rates in an unconfined eogenetic karst aquifer in two sites with different redox potential
This study integrates push-pull tracer tests (PPTT) with microbial characterization of extracted water via quantitative polymerase chain reaction (qPCR) and reverse transcriptase qPCR (RT-qPCR) of selected functional N transformation genes to quantify nitrate reduction mechanisms and rates in sites with different redox potential in a karst aquifer. PPTT treatments with nitrate (AN) and nitrate-fumAuthorsWesley R. Henson, Laibin Huang, Wendy D. Graham, Andrew OgramCRT--Cascade Routing Tool to define and visualize flow paths for grid-based watershed models
The U.S. Geological Survey Cascade Routing Tool (CRT) is a computer application for watershed models that include the coupled Groundwater and Surface-water FLOW model, GSFLOW, and the Precipitation-Runoff Modeling System (PRMS). CRT generates output to define cascading surface and shallow subsurface flow paths for grid-based model domains. CRT requires a land-surface elevation for each hydrologicAuthorsWesley R. Henson, Rose L. Medina, C. Justin Mayers, Richard G. Niswonger, R.S. Regan - Software
CalPUR-LUE
Estimating High Resolution Multi-Cropped Irrigated Land Use Using a Pesticide Use Reporting Database in California Estimating the amount of water needed for agriculture is vital for food and water security. These estimates rely on maps of crop type and acreage that have limited ground-truthing or represent multiple years or regional cropping patterns. In regions where crops change frequently or mCRT: Cascade Routing Tool to Define and Visualize Flow Paths for Grid-Based Watershed Models
The U.S. Geological Survey Cascade Routing Tool (CRT) is a computer application for watershed models that include the coupled Groundwater and Surface-water FLOW model GSFLOW and the Precipitation-Runoff Modeling System (PRMS). CRT generates output to define cascading surface and shallow subsurface flow paths for grid-based model domains.
MODPATH Observation Process (MODPATH-OBS)
The MODPATH-OBS (Hanson and others, 2013) computer program is designed to calculate simulated equivalents for observations related to advective groundwater transport that can be represented in a quantitative way by using simulated particle-tracking data.