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Paul Barlow

Paul Barlow is Chief of the Hydrologic Interpretive Branch in the New England Water Science Center.

Paul manages a diverse team of scientists involved in a wide range of water-resource investigations spanning environmental, watershed, and urban hydrology; integrated modeling; and statistical and geospatial analyses. He previously served as Chief of the Earth Systems Modeling Branch in the USGS Water Mission Area and as a staff hydrologist with the USGS Office of Groundwater. His technical expertise is modeling coupled groundwater/surface-water systems and the application of mathematical optimization to groundwater management, focusing in particular on the management of streamflow depletion by wells. He received an M.S. in Hydrology and Water Resources Administration from the University of Arizona and a Ph.D. in Environmental Engineering from the University of Connecticut. 

 

Science and Products

Filter Total Items: 45

U.S. Geological Survey Hydrologic Toolbox — A graphical and mapping interface for analysis of hydrologic data

The Hydrologic Toolbox is a Windows-based desktop software program that provides a graphical and mapping interface for analysis of hydrologic time-series data with a set of widely used and standardized computational methods. The software combines the analytical and statistical functionality provided in the U.S. Geological Survey Groundwater and Surface-Water Toolboxes and provides several enhancem
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Water Resources, New England Water Science Center

GW/SW-MST: A groundwater/surface-water method selection tool

Groundwater/surface-water (GW/SW) exchange and hyporheic processes are topics receiving increasing attention from the hydrologic community. Hydraulic, chemical, temperature, geophysical, and remote sensing methods are used to achieve various goals (e.g., inference of GW/SW exchange, mapping of bed materials, etc.), but the application of these methods is constrained by site conditions such as wate
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Water Resources

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 groundwater altitudes and streamflow contemporaneous wit
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Water Resources, Groundwater and Streamflow Information Program, Oklahoma-Texas Water Science Center, New England Water Science Center, Lower Mississippi-Gulf Water Science Center

Continuing progress toward a national assessment of water availability and use

Executive SummaryThe Omnibus Public Land Management Act of 2009 (Public Law 111—11) was passed into law on March 30, 2009. Subtitle F, also known as the SECURE Water Act, calls for the establishment of a “national water availability and use assessment program” within the U.S. Geological Survey (USGS). The USGS issued the first report on the program in 2013. Program progress over the period 2013–17
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Water Resources, Earth Resources Observation and Science Center, Water Availability and Use Science Program, Earth Resources Observation and Science (EROS) Center

Interstate water management of a “hidden” resource - Physical principles of groundwater hydrology

Groundwater systems are dynamic geologic environments in which water continuously flows from recharge areas to discharge areas at streams, springs, wetlands, coastal waters, and wells. Natural, predevelopment conditions within groundwater systems are changed by the introduction of wells and other human stresses that modify existing groundwater levels, flow paths, and hydrologic budgets. Groundwate
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Groundwater and Streamflow Information Program

Capture versus capture zones: Clarifying terminology related to sources of water to wells

The term capture, related to the source of water derived from wells, has been used in two distinct yet related contexts by the hydrologic community. The first is a water‐budget context, in which capture refers to decreases in the rates of groundwater outflow and (or) increases in the rates of recharge along head‐dependent boundaries of an aquifer in response to pumping. The second is a transport c
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Groundwater and Streamflow Information Program

A tool for efficient, model-independent management optimization under uncertainty

To fill a need for risk-based environmental management optimization, we have developed PESTPP-OPT, a model-independent tool for resource management optimization under uncertainty. PESTPP-OPT solves a sequential linear programming (SLP) problem and also implements (optional) efficient, “on-the-fly” (without user intervention) first-order, second-moment (FOSM) uncertainty techniques to estimate mode
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Water Resources, Upper Midwest Environmental Sciences Center, Upper Midwest Water Science Center

Depletion mapping and constrained optimization to support managing groundwater extraction

Groundwater models often serve as management tools to evaluate competing water uses including ecosystems, irrigated agriculture, industry, municipal supply, and others. Depletion potential mapping—showing the model-calculated potential impacts that wells have on stream baseflow—can form the basis for multiple potential management approaches in an oversubscribed basin. Specific management approache
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Water Resources, Upper Midwest Environmental Sciences Center, Upper Midwest Water Science Center

Groundwater flow model for the Little Plover River basin in Wisconsin’s Central Sands

The Little Plover River is a groundwater-fed stream in the sand plains region of central Wisconsin. In this region, sandy sediment deposited during or soon after the last glaciation forms an important unconfined sand and gravel aquifer. This aquifer supplies water for numerous high-capacity irrigation, municipal, and industrial wells that support a thriving agricultural industry. In recent years t
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Water Resources, Upper Midwest Environmental Sciences Center, Upper Midwest Water Science Center

Documentation of a restart option for the U.S. Geological Survey coupled Groundwater and Surface-Water Flow (GSFLOW) model

A new option to write and read antecedent conditions (also referred to as initial conditions) has been developed for the U.S. Geological Survey (USGS) Groundwater and Surface-Water Flow (GSFLOW) numerical, hydrologic simulation code. GSFLOW is an integration of the USGS Precipitation-Runoff Modeling System (PRMS) and USGS Modular Groundwater-Flow Model (MODFLOW), and provides three simulation mode
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Water Resources, Groundwater and Streamflow Information Program

U.S. Geological Survey groundwater toolbox, a graphical and mapping interface for analysis of hydrologic data (version 1.0): user guide for estimation of base flow, runoff, and groundwater recharge from streamflow data

This report is a user guide for the streamflow-hydrograph analysis methods provided with version 1.0 of the U.S. Geological Survey (USGS) Groundwater Toolbox computer program. These include six hydrograph-separation methods to determine the groundwater-discharge (base-flow) and surface-runoff components of streamflow—the Base-Flow Index (BFI; Standard and Modified), HYSEP (Fixed Interval, Sliding
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Water Resources, Groundwater and Streamflow Information Program

Optimization techniques using MODFLOW-GWM

An important application of optimization codes such as MODFLOW-GWM is to maximize water supply from unconfined aquifers subject to constraints involving surface-water depletion and drawdown. In optimizing pumping for a fish hatchery in a bedrock aquifer system overlain by glacial deposits in eastern Wisconsin, various features of the GWM-2000 code were used to overcome difficulties associated with
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Water Resources, Upper Midwest Environmental Sciences Center, Upper Midwest Water Science Center
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A satellite image of the Yukon River near Stevens Village, Alaska

Satellite-based Remote Sensing of River Discharge

The U.S. Geological Survey and NASA are collaborating on a study to develop methods to estimate river flows from satellite observations.
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Alaska Science Center, New England Water Science Center
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Satellite-based Remote Sensing of River Discharge

The U.S. Geological Survey and NASA are collaborating on a study to develop methods to estimate river flows from satellite observations.
Learn More
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USGS boat crew on Merrimack River, Massachusetts

Hydrologic Interpretive Program

The mission of the Hydrologic Interpretive Program is to work with stakeholders to design, carry out, and publish scientific studies addressing critical water-resources issues facing New England and the Nation.
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New England Water Science Center
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Hydrologic Interpretive Program

The mission of the Hydrologic Interpretive Program is to work with stakeholders to design, carry out, and publish scientific studies addressing critical water-resources issues facing New England and the Nation.
Learn More

Estimated and measured streamflow and groundwater-level data in the Mississippi Delta

This data release provides the data that support the findings in "Characterizing groundwater and surface-water interaction using hydrograph-separation techniques and groundwater-level data throughout the Mississippi Delta" by Killian and others (2019). There are two child items below: (1) Estimated baseflow includes the baseflow_est data and metadata that contain daily mean streamflow d
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Lower Mississippi-Gulf Water Science Center

National-Scale Grid to Support Regional Groundwater Availability Studies and a National Hydrogeologic Framework

The National Hydrogeologic Grid (NHG) dataset includes a raster and vector representation of 1-km cells defining a uniform grid that encompasses the continental United States. The value of each cell of the raster dataset corresponds to the 1-km cell number defined as 'cellnum' in the attributes of the vector data. The NHG consists of 4,000 rows and 4,980 columns, numbered from the top left corner
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Water Resources, Groundwater and Streamflow Information Program

U.S. Geological Survey Hydrologic Toolbox Software Archive

The U.S. Geological Survey Hydrologic Toolbox is a Windows-based desktop software program that provides a graphical and mapping interface for analysis of hydrologic time-series data with a set of widely used and standardized computational methods. The software combines the analytical and statistical functionality provided in the U.S. Geological Survey Groundwater and Surface-Water Toolboxes. The m
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New England Water Science Center

The Groundwater Toolbox: A Graphical and Mapping Interface for Analysis of Hydrologic Data

The Groundwater Toolbox is a graphical and mapping interface for analysis of hydrologic data. It provides methods to estimate many of the components of the water budget for a hydrologic basin, including precipitation, streamflow, base flow, runoff, groundwater recharge and evapotranspiration. As of May 2022, the Groundwater Toolbox has been superseded by the Hydrologic Toolbox.

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Water Resources

GWM: Groundwater Management Process for MODFLOW Using Optimization

GWM is a Groundwater Management Process for the U.S. Geological Survey modular three-dimensional groundwater model, MODFLOW.

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Water Resources, Water Resources
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Science in Support of Aquatic-Ecosystem Conservation and Restoration

Human land- and water-management practices have resulted in modifications to natural streamflow conditions and reduced the ecological health of...

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USGS Groundwater Toolbox: A New Way to Analyze Hydrologic Data

The U.S. Geological Survey (USGS) has released a convenient and informative new method for the analysis of groundwater and surface-water hydrologic...

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Science and Products