Robert J Welk
Rob is a Hydrologic Technician for the New York Water Science Center in the Coram Office.
Rob has been working for the USGS since 2015 and has performed a wide variety of job duties including maintenance of real-time continuous tide monitoring stations in Long Island embayments, collection of discrete water quality samples, and geospatial analysis of datasets. More recently Rob has moved toward a project support role within the NYWSC, providing statistical analysis, visualizations, and machine learning to facilitate project workflows in a reproducible manner. Rob frequently authors and reviews Data Release products and is proficient at creating detailed, accurate, and complete metadata records.
Professional Experience
USGS a Hydrologic Technician 2015-present.
Education and Certifications
M.S. Data Science and Analytics: CUNY School of Professional Studies, 2022
B.E. Earth Science and Environmental Engineering: City College of New York, 2016
Science and Products
Concentrations of 1,4-Dioxane, Per- and Polyfluorinated Substances (PFAS), Chlorofluorocarbons (CFCs), Methyl Tert-Butyl Ether (MTBE), and Trihalomethanes (THMs) in Groundwater, Nassau County, New York, 2019-2022
This data release contains 1-4 dioxane, per- and polyfluoroalkyl substances (PFAS), chlorofluorocarbons (CFCs), methyl tert-butyl ether (MTBE), and trihalomethanes (THMs) concentration data from groundwater samples collected from 78 monitoring wells in Nassau County New York. Samples were collected from May 2019 through December 2022 at wells ranging in depth from twenty-three feet to...
Phytoplankton data for samples collected at twelve large river sites throughout the United States, June through October 2019
This U.S. Geological Survey (USGS) Data Release provides phytoplankton data for samples collected from twelve large river sites throughout the United States, from June through October 2019. All data are reported as raw calculated values and are not rounded to USGS significant figures. The dataset includes all routine and quality assurance/quality control samples collected as part of a...
Geospatial dataset of the bathymetry, hydrodynamics, water quality, infrastructure, and channel condition of the Old Erie Canal from DeWitt to its junction with the current Erie Canal in Verona, near Rome, New York, 2018-19
This data release contains spatial datasets of bathymetry, water velocity, water quality, and infrastructure of a 30.8 mile reach of the Old Erie Canal between the Town of DeWitt and its junction with the current Erie Canal of the New York State Canal System in Verona, near Rome, New York during 2018 and 2019, and is released in support of Open-File Report 2021-1125; Wernly, J.F., 2022...
Geospatial bathymetry datasets for New York City's East of Hudson Reservoirs and Controlled Lakes
From May 2017 to November 2019, the U.S. Geological Survey conducted bathymetry surveys of New York City's East of Hudson Reservoirs. The East of Hudson Reservoirs consist of 16 reservoirs and controlled lakes in Putnam and Westchester County, New York, including Amawalk Reservoir, Bog Brook Reservoir, Boyd Corners Reservoir, Cross River Reservoir, Croton Falls Reservoir, Diverting...
Phytoplankton Data for Washington Park Lake, New York, September through October 2019
This U.S. Geological Survey (USGS) data release provides phytoplankton data collected from Washington Park Lake, New York, during September through October 2019. All data are reported as raw calculated values and are not rounded to USGS significant figures. This data release was produced in compliance with the open data requirements as a way to make scientific products associated with...
Coastal wetlands of Hudson Valley and New York City, New York
This data release contains coastal wetland synthesis products for the geographic region of Hudson Valley and New York City, New York. Metrics for resiliency, including unvegetated to vegetated ratio (UVVR), marsh elevation, and mean tidal range, are calculated for smaller units delineated from a Digital Elevation Model, providing the spatial variability of physical factors that influence...
Coastal wetlands of north shore Long Island, New York
This data release contains coastal wetland synthesis products for the geographic region of north shore Long Island, New York. Metrics for resiliency, including unvegetated to vegetated ratio (UVVR), marsh elevation, and mean tidal range, are calculated for smaller units delineated from a Digital Elevation Model, providing the spatial variability of physical factors that influence wetland...
Coastal wetlands of eastern Long Island, New York (ver. 2.0, March 2024)
This data release contains coastal wetland synthesis products for the geographic region of eastern Long Island, New York, including the north and south forks, Gardiners Island, and Fishers Island. Metrics for resiliency, including unvegetated to vegetated ratio (UVVR), marsh elevation, and mean tidal range, are calculated for smaller units delineated from a Digital Elevation Model...
Geospatial datasets of AUV observations including bottom dissolved oxygen in Great South Bay, Long Island, New York, August 2016
This dataset provides locations and values of water quality parameters from a four-day survey conducted between August 23, 2016 and August 26, 2016 using an Autonomous Underwater Vehicle (AUV) in Great South Bay, New York. Measured parameters include bottom dissolved oxygen (DO), salinity, specific conductance, water temperature, and pH. During the four day period, data was collected...
Monitoring and simulation of hydrology, suspended sediment, and nutrients in selected tributary watersheds of Lake Erie, New York
The U.S. Geological Survey, in cooperation with Erie County, New York, the New York State Department of Environmental Conservation, and the Great Lakes Restoration Initiative, collected water-quality samples in nine selected New York tributaries to Lake Erie, computed estimates of suspended sediment and nutrient loads using the R scripting package rloadest and used the Soil and Water...
Authors
Katherine R. Merriman, Benjamin N. Fisher, Elizabeth A. Nystrom, Aubrey R. Bunch, Robert J. Welk, William M. Kappel
Hydrologic analysis of an earthen embankment dam in southern Westchester County, New York
In 2001, the New York City Department of Environmental Protection installed 25 wells on the southern embankment of the Hillview Reservoir in Westchester County in an unsuccessful attempt to locate the source of a large seep (seep A) that began flowing continuously in 1999. In 2005, the U.S. Geological Survey began a cooperative study with the NYCDEP to characterize the hydrology of the...
Authors
Anthony Chu, Michael L. Noll, William D. Capurso, Robert J. Welk
Using microbial source tracking to identify fecal contamination sources in South Oyster Bay on Long Island, New York
The U.S. Geological Survey worked in cooperation with the New York State Department of Environmental Conservation to assess the potential sources of fecal contamination entering South Oyster Bay, a shallow embayment on the southern shore of Long Island, New York. Water samples are routinely collected by the New York State Department of Environmental Conservation in the bay and analyzed...
Authors
Tristen N. Tagliaferri, Shawn C. Fisher, Christopher M. Kephart, Natalie Cheung, Ariel P. Reed, Robert J. Welk
Using microbial source tracking to identify fecal contamination sources in Great South Bay on Long Island, New York
The U.S. Geological Survey worked in cooperation with the New York State Department of Environmental Conservation to assess the potential sources of fecal contamination entering a part of Great South Bay (referred to as Great South Bay for the purposes of this report) near the hamlets of West Sayville, Sayville, and Bayport on the southern shore of Suffolk County on Long Island, New York...
Authors
Tristen N. Tagliaferri, Shawn C. Fisher, Christopher M. Kephart, Natalie Cheung, Ariel P. Reed, Robert J. Welk
Using microbial source tracking to identify fecal contamination sources in Lake Montauk on Long Island, New York
The U.S. Geological Survey worked in cooperation with the Concerned Citizens of Montauk and the New York State Department of Environmental Conservation to assess the potential sources of fecal contamination entering Lake Montauk, an artificial embayment on the tip of the southern fork of Suffolk County, Long Island, New York. Water samples are routinely collected by the New York State...
Authors
Tristen N. Tagliaferri, Shawn C. Fisher, Christopher M. Kephart, Natalie Cheung, Ariel P. Reed, Robert J. Welk
Using microbial source tracking to identify fecal contamination sources in Sag Harbor on Long Island, New York
The U.S. Geological Survey worked in cooperation with the New York State Department of Environmental Conservation to assess the potential sources of fecal contamination entering Sag Harbor, an embayment complex on the northern shore of the south fork of Suffolk County, Long Island, New York. Water samples are routinely collected by the New York State Department of Environmental...
Authors
Tristen N. Tagliaferri, Shawn C. Fisher, Christopher M. Kephart, Natalie Cheung, Ariel P. Reed, Robert J. Welk
Using microbial source tracking to identify fecal contamination sources in Patchogue and Bellport Bays on Long Island, New York
The U.S. Geological Survey worked in cooperation with the New York State Department of Environmental Conservation to assess the potential sources of fecal contamination entering Patchogue and Bellport Bays, two embayments on the south shore of Suffolk County, Long Island, New York. Water samples are routinely collected by the New York State Department of Environmental Conservation in the...
Authors
Tristen N. Tagliaferri, Shawn C. Fisher, Christopher M. Kephart, Natalie Cheung, Ariel P. Reed, Robert J. Welk
Using microbial source tracking to identify contamination sources in Port Jefferson Harbor, Setauket Harbor, and Conscience Bay on Long Island, New York
The U.S. Geological Survey worked in cooperation with the New York State Department of Environmental Conservation to assess the potential sources of fecal contamination entering Port Jefferson Harbor, Setauket Harbor, and Conscience Bay, an embayment complex on the northern shore of Suffolk County, Long Island, New York. Water samples are routinely collected by the New York State...
Authors
Tristen N. Tagliaferri, Shawn C. Fisher, Christopher M. Kephart, Natalie Cheung, Ariel P. Reed, Robert J. Welk
Using microbial source tracking to identify fecal contamination sources in an embayment in Hempstead Harbor on Long Island, New York
The U.S. Geological Survey worked collaboratively with the New York State Department of Environmental Conservation to assess the potential sources of fecal contamination entering Hempstead Harbor, an embayment on the northern shore of Nassau County, Long Island, New York. Water samples are routinely collected by the New York State Department of Environmental Conservation in the harbor...
Authors
Tristen N. Tagliaferri, Shawn C. Fisher, Christopher M. Kephart, Natalie Cheung, Ariel P. Reed, Robert J. Welk
Bathymetry of New York City’s East of Hudson reservoirs and controlled lakes, 2017 to 2019
New York City maintains an extensive system of reservoirs and aqueducts to provide drinking water to its residents, including 16 reservoirs and controlled lakes in Westchester and Putnam Counties in southern New York, east of the Hudson River (also called “East of Hudson reservoirs and controlled lakes”). These reservoirs were put into service from 1842 to 1915, and their capacities have...
Authors
Elizabeth A. Nystrom, Courtney J. Huston, Robert J. Welk
Overview and methodology for a study to identify fecal contamination sources using microbial source tracking in seven embayments on Long Island, New York
Between June 2018 and July 2019, the U.S. Geological Survey collaborated with the New York State Department of Environmental Conservation to analyze water quality in seven embayments on Long Island, New York, for a study to examine fecal contamination using microbial source tracking. This report documents the approach, methodology, and quality-assurance data used in the study. All...
Authors
Tristen N. Tagliaferri, Shawn C. Fisher, Christopher M. Kephart, Natalie Cheung, Ariel P. Reed, Robert J. Welk
Long Island South Shore Estuary Reserve Coordinated Water Resources Monitoring Strategy
Executive SummaryThe Long Island South Shore Estuary Reserve Coordinated Water Resources Monitoring Strategy (CWRMS) provides an overview of the water-quality and ecological monitoring within the Reserve and presents suggestions from stakeholders for future data collection, data management, and coordination among monitoring programs. The South Shore Estuary Reserve, hereafter referred to...
Authors
Shawn C. Fisher, Robert J. Welk, Jason S. Finkelstein
Science and Products
Concentrations of 1,4-Dioxane, Per- and Polyfluorinated Substances (PFAS), Chlorofluorocarbons (CFCs), Methyl Tert-Butyl Ether (MTBE), and Trihalomethanes (THMs) in Groundwater, Nassau County, New York, 2019-2022
This data release contains 1-4 dioxane, per- and polyfluoroalkyl substances (PFAS), chlorofluorocarbons (CFCs), methyl tert-butyl ether (MTBE), and trihalomethanes (THMs) concentration data from groundwater samples collected from 78 monitoring wells in Nassau County New York. Samples were collected from May 2019 through December 2022 at wells ranging in depth from twenty-three feet to...
Phytoplankton data for samples collected at twelve large river sites throughout the United States, June through October 2019
This U.S. Geological Survey (USGS) Data Release provides phytoplankton data for samples collected from twelve large river sites throughout the United States, from June through October 2019. All data are reported as raw calculated values and are not rounded to USGS significant figures. The dataset includes all routine and quality assurance/quality control samples collected as part of a...
Geospatial dataset of the bathymetry, hydrodynamics, water quality, infrastructure, and channel condition of the Old Erie Canal from DeWitt to its junction with the current Erie Canal in Verona, near Rome, New York, 2018-19
This data release contains spatial datasets of bathymetry, water velocity, water quality, and infrastructure of a 30.8 mile reach of the Old Erie Canal between the Town of DeWitt and its junction with the current Erie Canal of the New York State Canal System in Verona, near Rome, New York during 2018 and 2019, and is released in support of Open-File Report 2021-1125; Wernly, J.F., 2022...
Geospatial bathymetry datasets for New York City's East of Hudson Reservoirs and Controlled Lakes
From May 2017 to November 2019, the U.S. Geological Survey conducted bathymetry surveys of New York City's East of Hudson Reservoirs. The East of Hudson Reservoirs consist of 16 reservoirs and controlled lakes in Putnam and Westchester County, New York, including Amawalk Reservoir, Bog Brook Reservoir, Boyd Corners Reservoir, Cross River Reservoir, Croton Falls Reservoir, Diverting...
Phytoplankton Data for Washington Park Lake, New York, September through October 2019
This U.S. Geological Survey (USGS) data release provides phytoplankton data collected from Washington Park Lake, New York, during September through October 2019. All data are reported as raw calculated values and are not rounded to USGS significant figures. This data release was produced in compliance with the open data requirements as a way to make scientific products associated with...
Coastal wetlands of Hudson Valley and New York City, New York
This data release contains coastal wetland synthesis products for the geographic region of Hudson Valley and New York City, New York. Metrics for resiliency, including unvegetated to vegetated ratio (UVVR), marsh elevation, and mean tidal range, are calculated for smaller units delineated from a Digital Elevation Model, providing the spatial variability of physical factors that influence...
Coastal wetlands of north shore Long Island, New York
This data release contains coastal wetland synthesis products for the geographic region of north shore Long Island, New York. Metrics for resiliency, including unvegetated to vegetated ratio (UVVR), marsh elevation, and mean tidal range, are calculated for smaller units delineated from a Digital Elevation Model, providing the spatial variability of physical factors that influence wetland...
Coastal wetlands of eastern Long Island, New York (ver. 2.0, March 2024)
This data release contains coastal wetland synthesis products for the geographic region of eastern Long Island, New York, including the north and south forks, Gardiners Island, and Fishers Island. Metrics for resiliency, including unvegetated to vegetated ratio (UVVR), marsh elevation, and mean tidal range, are calculated for smaller units delineated from a Digital Elevation Model...
Geospatial datasets of AUV observations including bottom dissolved oxygen in Great South Bay, Long Island, New York, August 2016
This dataset provides locations and values of water quality parameters from a four-day survey conducted between August 23, 2016 and August 26, 2016 using an Autonomous Underwater Vehicle (AUV) in Great South Bay, New York. Measured parameters include bottom dissolved oxygen (DO), salinity, specific conductance, water temperature, and pH. During the four day period, data was collected...
Monitoring and simulation of hydrology, suspended sediment, and nutrients in selected tributary watersheds of Lake Erie, New York
The U.S. Geological Survey, in cooperation with Erie County, New York, the New York State Department of Environmental Conservation, and the Great Lakes Restoration Initiative, collected water-quality samples in nine selected New York tributaries to Lake Erie, computed estimates of suspended sediment and nutrient loads using the R scripting package rloadest and used the Soil and Water...
Authors
Katherine R. Merriman, Benjamin N. Fisher, Elizabeth A. Nystrom, Aubrey R. Bunch, Robert J. Welk, William M. Kappel
Hydrologic analysis of an earthen embankment dam in southern Westchester County, New York
In 2001, the New York City Department of Environmental Protection installed 25 wells on the southern embankment of the Hillview Reservoir in Westchester County in an unsuccessful attempt to locate the source of a large seep (seep A) that began flowing continuously in 1999. In 2005, the U.S. Geological Survey began a cooperative study with the NYCDEP to characterize the hydrology of the...
Authors
Anthony Chu, Michael L. Noll, William D. Capurso, Robert J. Welk
Using microbial source tracking to identify fecal contamination sources in South Oyster Bay on Long Island, New York
The U.S. Geological Survey worked in cooperation with the New York State Department of Environmental Conservation to assess the potential sources of fecal contamination entering South Oyster Bay, a shallow embayment on the southern shore of Long Island, New York. Water samples are routinely collected by the New York State Department of Environmental Conservation in the bay and analyzed...
Authors
Tristen N. Tagliaferri, Shawn C. Fisher, Christopher M. Kephart, Natalie Cheung, Ariel P. Reed, Robert J. Welk
Using microbial source tracking to identify fecal contamination sources in Great South Bay on Long Island, New York
The U.S. Geological Survey worked in cooperation with the New York State Department of Environmental Conservation to assess the potential sources of fecal contamination entering a part of Great South Bay (referred to as Great South Bay for the purposes of this report) near the hamlets of West Sayville, Sayville, and Bayport on the southern shore of Suffolk County on Long Island, New York...
Authors
Tristen N. Tagliaferri, Shawn C. Fisher, Christopher M. Kephart, Natalie Cheung, Ariel P. Reed, Robert J. Welk
Using microbial source tracking to identify fecal contamination sources in Lake Montauk on Long Island, New York
The U.S. Geological Survey worked in cooperation with the Concerned Citizens of Montauk and the New York State Department of Environmental Conservation to assess the potential sources of fecal contamination entering Lake Montauk, an artificial embayment on the tip of the southern fork of Suffolk County, Long Island, New York. Water samples are routinely collected by the New York State...
Authors
Tristen N. Tagliaferri, Shawn C. Fisher, Christopher M. Kephart, Natalie Cheung, Ariel P. Reed, Robert J. Welk
Using microbial source tracking to identify fecal contamination sources in Sag Harbor on Long Island, New York
The U.S. Geological Survey worked in cooperation with the New York State Department of Environmental Conservation to assess the potential sources of fecal contamination entering Sag Harbor, an embayment complex on the northern shore of the south fork of Suffolk County, Long Island, New York. Water samples are routinely collected by the New York State Department of Environmental...
Authors
Tristen N. Tagliaferri, Shawn C. Fisher, Christopher M. Kephart, Natalie Cheung, Ariel P. Reed, Robert J. Welk
Using microbial source tracking to identify fecal contamination sources in Patchogue and Bellport Bays on Long Island, New York
The U.S. Geological Survey worked in cooperation with the New York State Department of Environmental Conservation to assess the potential sources of fecal contamination entering Patchogue and Bellport Bays, two embayments on the south shore of Suffolk County, Long Island, New York. Water samples are routinely collected by the New York State Department of Environmental Conservation in the...
Authors
Tristen N. Tagliaferri, Shawn C. Fisher, Christopher M. Kephart, Natalie Cheung, Ariel P. Reed, Robert J. Welk
Using microbial source tracking to identify contamination sources in Port Jefferson Harbor, Setauket Harbor, and Conscience Bay on Long Island, New York
The U.S. Geological Survey worked in cooperation with the New York State Department of Environmental Conservation to assess the potential sources of fecal contamination entering Port Jefferson Harbor, Setauket Harbor, and Conscience Bay, an embayment complex on the northern shore of Suffolk County, Long Island, New York. Water samples are routinely collected by the New York State...
Authors
Tristen N. Tagliaferri, Shawn C. Fisher, Christopher M. Kephart, Natalie Cheung, Ariel P. Reed, Robert J. Welk
Using microbial source tracking to identify fecal contamination sources in an embayment in Hempstead Harbor on Long Island, New York
The U.S. Geological Survey worked collaboratively with the New York State Department of Environmental Conservation to assess the potential sources of fecal contamination entering Hempstead Harbor, an embayment on the northern shore of Nassau County, Long Island, New York. Water samples are routinely collected by the New York State Department of Environmental Conservation in the harbor...
Authors
Tristen N. Tagliaferri, Shawn C. Fisher, Christopher M. Kephart, Natalie Cheung, Ariel P. Reed, Robert J. Welk
Bathymetry of New York City’s East of Hudson reservoirs and controlled lakes, 2017 to 2019
New York City maintains an extensive system of reservoirs and aqueducts to provide drinking water to its residents, including 16 reservoirs and controlled lakes in Westchester and Putnam Counties in southern New York, east of the Hudson River (also called “East of Hudson reservoirs and controlled lakes”). These reservoirs were put into service from 1842 to 1915, and their capacities have...
Authors
Elizabeth A. Nystrom, Courtney J. Huston, Robert J. Welk
Overview and methodology for a study to identify fecal contamination sources using microbial source tracking in seven embayments on Long Island, New York
Between June 2018 and July 2019, the U.S. Geological Survey collaborated with the New York State Department of Environmental Conservation to analyze water quality in seven embayments on Long Island, New York, for a study to examine fecal contamination using microbial source tracking. This report documents the approach, methodology, and quality-assurance data used in the study. All...
Authors
Tristen N. Tagliaferri, Shawn C. Fisher, Christopher M. Kephart, Natalie Cheung, Ariel P. Reed, Robert J. Welk
Long Island South Shore Estuary Reserve Coordinated Water Resources Monitoring Strategy
Executive SummaryThe Long Island South Shore Estuary Reserve Coordinated Water Resources Monitoring Strategy (CWRMS) provides an overview of the water-quality and ecological monitoring within the Reserve and presents suggestions from stakeholders for future data collection, data management, and coordination among monitoring programs. The South Shore Estuary Reserve, hereafter referred to...
Authors
Shawn C. Fisher, Robert J. Welk, Jason S. Finkelstein