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Ward Sanford

Ward Sanford is a Research Hydrologist with the USGS Water Resources Mission Area. 

Dr. Ward Sanford received a B.S. from Purdue University in Geology in 1983 and a PhD in Hydrogeology from Penn State University in 1987.  He has been with the USGS Water Resources Discipline's National Research Program full time since 1987.  He has been active in research on problems of regional groundwater flow and transport throughout the United States and the world.   Field areas have included West Texas, Central New Mexico, Virginia, Thailand, Hungary, Central America, and the United Arab Emirates.  He has been a consultant to the U. S. State Department and the International Atomic Energy Agency (IAEA).  He received the Geological Society of America Young Scientist Award (Donath Medal) in 1995 and the National Ground Water Association John Hem Award in 2000.   He is coauthor of the widely used graduate level textbook entitled "Groundwater in Geologic Processes".  He is a senior fellow of the Geological Society of America, and a member of the American Geophysical Union, the National Ground Water Association, and the International Association of Hydrogeologists.

 

Science and Products

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USGS science for a changing world logo

Moving towards EarthMAP: Establishing linkages among USGS land use, water use, runoff, and recharge models

Understanding and anticipating change in dynamic Earth systems is vital for societal adaptation and welfare. USGS possesses the multidisciplinary capabilities to anticipate Earth systems change, yet our work is often bound within a single discipline and/or Mission Area. The proposed work breaks new ground in moving USGS towards an interdisciplinary predictive modeling framework. We are initially l
By
Community for Data Integration (CDI)
link

Moving towards EarthMAP: Establishing linkages among USGS land use, water use, runoff, and recharge models

Understanding and anticipating change in dynamic Earth systems is vital for societal adaptation and welfare. USGS possesses the multidisciplinary capabilities to anticipate Earth systems change, yet our work is often bound within a single discipline and/or Mission Area. The proposed work breaks new ground in moving USGS towards an interdisciplinary predictive modeling framework. We are initially l
Learn More
link
USGS science for a changing world logo

Integrating GRACE Satellite and Ground-based Estimates of Groundwater Storage Changes

Groundwater storage depletion is a critical issue for many of the major aquifers in the U.S., particularly during intense droughts. The GRACE (Gravity Recovery and Climate Experiment) satellites launched in 2002, with sensors designed to measure changes in the Earth’s gravitational field at large spatial scales (≥ ~200,000 km2). These changes are primarily driven by changes in water storage on the...
By
John Wesley Powell Center for Analysis and Synthesis
link

Integrating GRACE Satellite and Ground-based Estimates of Groundwater Storage Changes

Groundwater storage depletion is a critical issue for many of the major aquifers in the U.S., particularly during intense droughts. The GRACE (Gravity Recovery and Climate Experiment) satellites launched in 2002, with sensors designed to measure changes in the Earth’s gravitational field at large spatial scales (≥ ~200,000 km2). These changes are primarily driven by changes in water storage on the...
Learn More
Filter Total Items: 63

Estimating mean long-term hydrologic budget components for watersheds and counties: An application to the commonwealth of Virginia, USA

Mean long-term hydrologic budget components, such as recharge and base flow, are often difficult to estimate because they can vary substantially in space and time. Mean long-term fluxes were calculated in this study for precipitation, surface runoff, infiltration, total evapotranspiration (ET), riparian ET, recharge, base flow (or groundwater discharge) and net total outflow using long-term estima
Authors
Ward E. Sanford, David L. Nelms, Jason P. Pope, David L. Selnick
By
Water Resources Mission Area

Dating base flow in streams using dissolved gases and diurnal temperature changes

A method is presented for using dissolved CFCs or SF6 to estimate the apparent age of stream base flow by indirectly estimating the mean concentration of the tracer in the inflowing groundwater. The mean value is estimated simultaneously with the mean residence times of the gas and water in the stream by sampling the stream for one or both age tracers, along with dissolved nitrogen and argon at a
Authors
Ward E. Sanford, Gerolamo C. Casile, Karl B. Haase
By
Water Resources Mission Area

Measurements of HFC-134a and HCFC-22 in groundwater and unsaturated-zone air: implications for HFCs and HCFCs as dating tracers

A new analytical method using gas chromatography with an atomic emission detector (GC–AED) was developed for measurement of ambient concentrations of hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs) in soil, air, and groundwater, with the goal of determining their utility as groundwater age tracers. The analytical detection limits of HCFC-22 (difluorochloromethane, CHClF2) and HFC-13
Authors
Karl B. Haase, Eurybiades Busenberg, Niel Plummer, Gerolamo Casile, Ward E. Sanford
By
Water Resources Mission Area, Ecosystems Mission Area, Toxic Substances Hydrology, Environmental Health Program

Distinguishing seawater from geologic brine in saline coastal groundwater using radium-226; an example from the Sabkha of the UAE

Sabkhat (Salt flats) are common geographic features of low-lying marine coastal areas that develop under hyper-arid climatic conditions. They are characterized by the presence of highly concentrated saline solutions and evaporitic minerals, and have been cited in the geologic literature as present-day representations of hyper-arid regional paleohydrogeology, paleoclimatology, coastal processes, an
Authors
Thomas F. Kraemer, Warren W. Wood, Ward E. Sanford
By
Water Resources Mission Area

Evidence for high salinity of Early Cretaceous sea water from the Chesapeake Bay crater

High salinity groundwater more than 1000 metres deep in the Atlantic Coastal Plain of the United States has been documented in several locations1,2, most recently within the 35 million-year-old Chesapeake Bay impact crater3,4,5. Suggestions for the origin of increased salinity in the crater have included evaporite dissolution6, osmosis6, and evaporation from heating7 associated with the bolide imp
Authors
Ward E. Sanford, Michael W. Doughten, Tyler B. Coplen, Andrew G. Hunt, Thomas D. Bullen
By
Water Resources Mission Area, Chesapeake Bay Activities

Quantifying groundwater’s role in delaying improvements to Chesapeake Bay water quality

A study has been undertaken to determine the time required for the effects of nitrogen-reducing best management practices (BMPs) implemented at the land surface to reach the Chesapeake Bay via groundwater transport to streams. To accomplish this, a nitrogen mass-balance regression (NMBR) model was developed and applied to seven watersheds on the Delmarva Peninsula. The model included the distribut
Authors
Ward E. Sanford, Jason P. Pope
By
Water Resources Mission Area, Chesapeake Bay Activities, Virginia and West Virginia Water Science Center

Characterization and conceptualization of groundwater flow systems

This chapter discusses some of the fundamental concepts, data needs and approaches that aid in developing a general understanding of a groundwater system. Principles of the hydrological cycle are reviewed; the processes of recharge and discharge in aquifer systems; types of geological, hydrological and hydraulic data needed to describe the hydrogeological framework of an aquifer system; factors af
Authors
Niel Plummer, W. E. Sanford, P. D. Glynn
By
Water Resources Mission Area

Defining groundwater age

This book investigates applications of selected chemical and isotopic substances that can be used to recognize and interpret age information pertaining to ‘old’ groundwater (defined as water that was recharged on a timescale from approximately 1000 to more than 1 000 000 a). However, as discussed below, only estimates of the ‘age’ of water extracted from wells can be inferred. These groundwater ag
Authors
T. Torgersen, R. Purtschert, F. M. Phillips, Niel Plummer, W. E. Sanford, A. Suckow
By
Water Resources Mission Area

Numerical flow models and their calibration using tracer based ages

Any estimate of ‘age’ of a groundwater sample based on environmental tracers requires some form of geochemical model to interpret the tracer chemistry (chapter 3) and is, therefore, referred to in this chapter as a tracer model age. the tracer model age of a groundwater sample can be useful for obtaining information on the residence time and replenishment rate of an aquifer system, but that type o
Authors
W. Sanford
By
Water Resources Mission Area

Case study Middle Rio Grande Basin, New Mexico, USA

Chemical and isotopic patterns in groundwater can record characteristics of water sources, flow directions, and groundwater-age information. This hydrochemical information can be useful in refining conceptualization of groundwater flow, in calibration of numerical models of groundwater flow, and in estimation of paleo and modern recharge rates. This case study shows how chemical and isotopic dat
Authors
Niel Plummer, W. Sanford
By
Water Resources Mission Area

Estimation of evapotranspiration across the conterminous United States using a regression with climate and land-cover data

Evapotranspiration (ET) is an important quantity for water resource managers to know because it often represents the largest sink for precipitation (P) arriving at the land surface. In order to estimate actual ET across the conterminous United States (U.S.) in this study, a water-balance method was combined with a climate and land-cover regression equation. Precipitation and streamflow records wer
Authors
Ward E. Sanford, David L. Selnick
By
Water Resources Mission Area

Simulation of groundwater flow in the shallow aquifer system of the Delmarva Peninsula, Maryland and Delaware

Estimating future loadings of nitrogen to the Chesapeake Bay requires knowledge about the groundwater flow system and the traveltime of water and chemicals between recharge at the water table and the discharge to streams and directly to the bay. The Delmarva Peninsula has a relatively large proportion of its land devoted to agriculture and a large associated nitrogen load in groundwater that has t
Authors
Ward E. Sanford, Jason P. Pope, David L. Selnick, Ryan F. Stumvoll
By
Water Resources Mission Area, Chesapeake Bay Activities
link

Seminar Sept 17th at 1 pm ET - Climate Extremes and Irrigation Water Source and Use Dominate Water Storage Changes Monitored by GRACE Satellites in Major U.S. Aquifers

Join us online, Sept 17th at 1 pm ET, 11 MT  - Join Microsoft Teams Meeting (Learn more about Teams | Meeting options)

A Seminar by Bridget Scanlon of...

Read Article
link

The Chesapeake Bay gets some good news

EARTH Magazine — by Mary Caperton Morton — November 4, 2019

Read Article

Science and Products

  • Science
    link
    USGS science for a changing world logo

    Moving towards EarthMAP: Establishing linkages among USGS land use, water use, runoff, and recharge models

    Understanding and anticipating change in dynamic Earth systems is vital for societal adaptation and welfare. USGS possesses the multidisciplinary capabilities to anticipate Earth systems change, yet our work is often bound within a single discipline and/or Mission Area. The proposed work breaks new ground in moving USGS towards an interdisciplinary predictive modeling framework. We are initially l
    By
    Community for Data Integration (CDI)
    link

    Moving towards EarthMAP: Establishing linkages among USGS land use, water use, runoff, and recharge models

    Understanding and anticipating change in dynamic Earth systems is vital for societal adaptation and welfare. USGS possesses the multidisciplinary capabilities to anticipate Earth systems change, yet our work is often bound within a single discipline and/or Mission Area. The proposed work breaks new ground in moving USGS towards an interdisciplinary predictive modeling framework. We are initially l
    Learn More
    link
    USGS science for a changing world logo

    Integrating GRACE Satellite and Ground-based Estimates of Groundwater Storage Changes

    Groundwater storage depletion is a critical issue for many of the major aquifers in the U.S., particularly during intense droughts. The GRACE (Gravity Recovery and Climate Experiment) satellites launched in 2002, with sensors designed to measure changes in the Earth’s gravitational field at large spatial scales (≥ ~200,000 km2). These changes are primarily driven by changes in water storage on the...
    By
    John Wesley Powell Center for Analysis and Synthesis
    link

    Integrating GRACE Satellite and Ground-based Estimates of Groundwater Storage Changes

    Groundwater storage depletion is a critical issue for many of the major aquifers in the U.S., particularly during intense droughts. The GRACE (Gravity Recovery and Climate Experiment) satellites launched in 2002, with sensors designed to measure changes in the Earth’s gravitational field at large spatial scales (≥ ~200,000 km2). These changes are primarily driven by changes in water storage on the...
    Learn More
  • Publications
    Filter Total Items: 63

    Estimating mean long-term hydrologic budget components for watersheds and counties: An application to the commonwealth of Virginia, USA

    Mean long-term hydrologic budget components, such as recharge and base flow, are often difficult to estimate because they can vary substantially in space and time. Mean long-term fluxes were calculated in this study for precipitation, surface runoff, infiltration, total evapotranspiration (ET), riparian ET, recharge, base flow (or groundwater discharge) and net total outflow using long-term estima
    Authors
    Ward E. Sanford, David L. Nelms, Jason P. Pope, David L. Selnick
    By
    Water Resources Mission Area

    Dating base flow in streams using dissolved gases and diurnal temperature changes

    A method is presented for using dissolved CFCs or SF6 to estimate the apparent age of stream base flow by indirectly estimating the mean concentration of the tracer in the inflowing groundwater. The mean value is estimated simultaneously with the mean residence times of the gas and water in the stream by sampling the stream for one or both age tracers, along with dissolved nitrogen and argon at a
    Authors
    Ward E. Sanford, Gerolamo C. Casile, Karl B. Haase
    By
    Water Resources Mission Area

    Measurements of HFC-134a and HCFC-22 in groundwater and unsaturated-zone air: implications for HFCs and HCFCs as dating tracers

    A new analytical method using gas chromatography with an atomic emission detector (GC–AED) was developed for measurement of ambient concentrations of hydrochlorofluorocarbons (HCFCs) and hydrofluorocarbons (HFCs) in soil, air, and groundwater, with the goal of determining their utility as groundwater age tracers. The analytical detection limits of HCFC-22 (difluorochloromethane, CHClF2) and HFC-13
    Authors
    Karl B. Haase, Eurybiades Busenberg, Niel Plummer, Gerolamo Casile, Ward E. Sanford
    By
    Water Resources Mission Area, Ecosystems Mission Area, Toxic Substances Hydrology, Environmental Health Program

    Distinguishing seawater from geologic brine in saline coastal groundwater using radium-226; an example from the Sabkha of the UAE

    Sabkhat (Salt flats) are common geographic features of low-lying marine coastal areas that develop under hyper-arid climatic conditions. They are characterized by the presence of highly concentrated saline solutions and evaporitic minerals, and have been cited in the geologic literature as present-day representations of hyper-arid regional paleohydrogeology, paleoclimatology, coastal processes, an
    Authors
    Thomas F. Kraemer, Warren W. Wood, Ward E. Sanford
    By
    Water Resources Mission Area

    Evidence for high salinity of Early Cretaceous sea water from the Chesapeake Bay crater

    High salinity groundwater more than 1000 metres deep in the Atlantic Coastal Plain of the United States has been documented in several locations1,2, most recently within the 35 million-year-old Chesapeake Bay impact crater3,4,5. Suggestions for the origin of increased salinity in the crater have included evaporite dissolution6, osmosis6, and evaporation from heating7 associated with the bolide imp
    Authors
    Ward E. Sanford, Michael W. Doughten, Tyler B. Coplen, Andrew G. Hunt, Thomas D. Bullen
    By
    Water Resources Mission Area, Chesapeake Bay Activities

    Quantifying groundwater’s role in delaying improvements to Chesapeake Bay water quality

    A study has been undertaken to determine the time required for the effects of nitrogen-reducing best management practices (BMPs) implemented at the land surface to reach the Chesapeake Bay via groundwater transport to streams. To accomplish this, a nitrogen mass-balance regression (NMBR) model was developed and applied to seven watersheds on the Delmarva Peninsula. The model included the distribut
    Authors
    Ward E. Sanford, Jason P. Pope
    By
    Water Resources Mission Area, Chesapeake Bay Activities, Virginia and West Virginia Water Science Center

    Characterization and conceptualization of groundwater flow systems

    This chapter discusses some of the fundamental concepts, data needs and approaches that aid in developing a general understanding of a groundwater system. Principles of the hydrological cycle are reviewed; the processes of recharge and discharge in aquifer systems; types of geological, hydrological and hydraulic data needed to describe the hydrogeological framework of an aquifer system; factors af
    Authors
    Niel Plummer, W. E. Sanford, P. D. Glynn
    By
    Water Resources Mission Area

    Defining groundwater age

    This book investigates applications of selected chemical and isotopic substances that can be used to recognize and interpret age information pertaining to ‘old’ groundwater (defined as water that was recharged on a timescale from approximately 1000 to more than 1 000 000 a). However, as discussed below, only estimates of the ‘age’ of water extracted from wells can be inferred. These groundwater ag
    Authors
    T. Torgersen, R. Purtschert, F. M. Phillips, Niel Plummer, W. E. Sanford, A. Suckow
    By
    Water Resources Mission Area

    Numerical flow models and their calibration using tracer based ages

    Any estimate of ‘age’ of a groundwater sample based on environmental tracers requires some form of geochemical model to interpret the tracer chemistry (chapter 3) and is, therefore, referred to in this chapter as a tracer model age. the tracer model age of a groundwater sample can be useful for obtaining information on the residence time and replenishment rate of an aquifer system, but that type o
    Authors
    W. Sanford
    By
    Water Resources Mission Area

    Case study Middle Rio Grande Basin, New Mexico, USA

    Chemical and isotopic patterns in groundwater can record characteristics of water sources, flow directions, and groundwater-age information. This hydrochemical information can be useful in refining conceptualization of groundwater flow, in calibration of numerical models of groundwater flow, and in estimation of paleo and modern recharge rates. This case study shows how chemical and isotopic dat
    Authors
    Niel Plummer, W. Sanford
    By
    Water Resources Mission Area

    Estimation of evapotranspiration across the conterminous United States using a regression with climate and land-cover data

    Evapotranspiration (ET) is an important quantity for water resource managers to know because it often represents the largest sink for precipitation (P) arriving at the land surface. In order to estimate actual ET across the conterminous United States (U.S.) in this study, a water-balance method was combined with a climate and land-cover regression equation. Precipitation and streamflow records wer
    Authors
    Ward E. Sanford, David L. Selnick
    By
    Water Resources Mission Area

    Simulation of groundwater flow in the shallow aquifer system of the Delmarva Peninsula, Maryland and Delaware

    Estimating future loadings of nitrogen to the Chesapeake Bay requires knowledge about the groundwater flow system and the traveltime of water and chemicals between recharge at the water table and the discharge to streams and directly to the bay. The Delmarva Peninsula has a relatively large proportion of its land devoted to agriculture and a large associated nitrogen load in groundwater that has t
    Authors
    Ward E. Sanford, Jason P. Pope, David L. Selnick, Ryan F. Stumvoll
    By
    Water Resources Mission Area, Chesapeake Bay Activities
  • News
    link

    Seminar Sept 17th at 1 pm ET - Climate Extremes and Irrigation Water Source and Use Dominate Water Storage Changes Monitored by GRACE Satellites in Major U.S. Aquifers

    Join us online, Sept 17th at 1 pm ET, 11 MT  - Join Microsoft Teams Meeting (Learn more about Teams | Meeting options)

    A Seminar by Bridget Scanlon of...

    Read Article
    link

    The Chesapeake Bay gets some good news

    EARTH Magazine — by Mary Caperton Morton — November 4, 2019

    Read Article