Anthony Chu
Tony is a hydrologist at the USGS New York Water Science Center.
Has worked on numerous multi-disciplinary projects that included: saltwater intrusion, hydrogeology, water-use, hydrogeologic mapping, fractured-rock hydrology, and borehole, surface, and marine geophysical applications to aid in tunnel construction and engineering safety.
Professional Experience
Hydrologist (Geology), U.S. Geological Survey, New York Water Science Center, Coram, 1993—Present
Hydrologic Technician, U.S. Geological Survey, New York Water Science Center, Coram, 1988—1993
Education and Certifications
M.S. in Hydrogeology, Stony Brook University, 1994
B.A. in Earth and Space Sciences, Stony Brook University, 1988
Science and Products
Filter Total Items: 23
Accuracy assessment of three-dimensional point cloud data collected with a scanning total station on Shinnecock Nation Tribal lands in Suffolk County, New York
A combined point cloud of about 85.6 million points was collected during 27 scans of a section of the western shoreline along the Shinnecock Peninsula of Suffolk County, New York, to document baseline geospatial conditions during July and October 2022 using a scanning total station. The three-dimensional accuracy of the combined point cloud is assessed to identify potential systematic error source
Authors
Michael L. Noll, William D. Capurso, Anthony Chu
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 local groun
Authors
Anthony Chu, Michael L. Noll, William D. Capurso, Robert J. Welk
Hydrologic effects of leakage from the Catskill Aqueduct on the bedrock-aquifer system near High Falls, New York, November 2019–January 2020
Historical observations by the New York City Department of Environmental Protection (NYCDEP) indicate that the Rondout pressure tunnel has been leaking in the vicinity of the hamlet of High Falls, New York. In the 74 days from November 11, 2019, to January 23, 2020, NYCDEP shut down and partially dewatered the pressure tunnel for inspection and repairs. On November 5–7, 2019 (during normal tunnel
Authors
Anthony Chu, Michael L. Noll, William D. Capurso
Slug-test analysis of selected wells at an earthen dam site in southern Westchester County, New York
In 2005, the U.S. Geological Survey began a cooperative study with the New York City Department of Environmental Protection to characterize the local groundwater-flow system and identify potential sources of seeps on the southern embankment of the Hillview Reservoir in southern Westchester County, New York. The earthen embankment comprises low-permeability glacial clays that were excavated from th
Authors
Michael L. Noll, Anthony Chu, William D. Capurso
Groundwater-level data from an earthen dam site in southern Westchester County, New York
In 2005, the U.S. Geological Survey began a cooperative study with New York City Department of Environmental Protection to characterize the local groundwater-flow system and identify potential sources of seeps on the southern embankment of the Hillview Reservoir in Westchester County, New York. Groundwater levels were collected at 49 wells at Hillview Reservoir, and 1 well in northern Bronx County
Authors
Michael L. Noll, Anthony Chu
Water-quality data from an earthen dam site in southern Westchester County, New York, 2015
The U.S. Geological Survey, in cooperation with the New York City Department of Environmental Protection, sampled 37 sites in the reservoir area for nutrients, major ions, metals, pesticides and their degradates, volatile organic compounds, temperature, pH, and specific conductance during fall 2015. Data collection was done to characterize the local groundwater-flow system and identify potential s
Authors
Anthony Chu, Michael L. Noll
Detecting temporal change in land-surface altitude using robotic land-surveying techniques and geographic information system applications at an earthen dam site in Southern Westchester County, New York
In 2005, the U.S. Geological Survey began a cooperative study with New York City Department of Environmental Protection to characterize the local groundwater-flow system and identify potential sources of seeps on the southern embankment at the Hillview Reservoir in southern Westchester County, New York. Monthly site inspections at the reservoir indicated an approximately 90-square-foot depression
Authors
Michael L. Noll, Anthony Chu
Delineation of fractures, foliation, and groundwater of the bedrock at a geothermal feasibility site on Roosevelt Island, New York County, New York
Advanced borehole-geophysical methods were used to investigate the hydrogeology of the crystalline bedrock in three boreholes on Roosevelt Island, New York County, New York. Cornell University was evaluating the feasibility of using geothermal energy for a future campus at the site. The borehole-logging techniques were used to delineate bedrock fractures, foliation, and groundwater-flow zones of t
Authors
Frederick Stumm, Anthony Chu, Michael D. Como, Michael L. Noll, Peter K. Joesten
Delineation of fractures, foliation, and groundwater-flow zones of the bedrock at the Harlem River Tunnel in northern New York County, New York
Advanced borehole-geophysical methods were used to investigate the hydrogeology of the crystalline bedrock in 36 boreholes on the northernmost part of New York County, New York, for the construction of a utilities tunnel beneath the Harlem River. The borehole-logging techniques were used to delineate bedrock fractures, foliation, and groundwater-flow zones in test boreholes at the site. Fracture i
Authors
Frederick Stumm, Anthony Chu, Peter K. Joesten, Michael L. Noll, Michael D. Como
Geophysical and hydrologic analysis of an earthen dam site in southern Westchester County, New York
Ninety percent of the drinking water for New York City passes through the Hillview Reservoir facility in the City of Yonkers, Westchester County, New York. In the past, several seeps located downslope from the reservoir have flowed out from the side of the steepest slope at the southern end of the earthen embankment. One seep that has been flowing continuously was discovered during an inspection o
Authors
Anthony Chu, Frederick Stumm, Peter K. Joesten, Michael L. Noll
Preliminary assessment of water chemistry related to groundwater flooding in Wawarsing, New York, 2009-11
Water-quality samples collected in an area prone to groundwater flooding in Wawarsing, New York, were analyzed and assessed to better understand the hydrologic system and to aid in the assessment of contributing water sources. Above average rainfall over the past decade, and the presence of a pressurized water tunnel that passes about 700 feet beneath Wawarsing, could both contribute to groundwate
Authors
Craig J. Brown, David A. Eckhardt, Frederick Stumm, Anthony Chu
Preliminary analysis of the hydrologic effects of temporary shutdowns of the Rondout-West Branch Water Tunnel on the groundwater-flow system in Wawarsing, New York
Flooding of streets and residential basements, and bacterial contamination of private-supply wells with Escherichia coli (E. coli) are recurring problems in the Rondout Valley near the Town of Wawarsing, Ulster County, New York. Leakage from the Rondout-West Branch (RWB) Water Tunnel and above-normal precipitation have been suspected of causing elevated groundwater levels and basement flooding. Th
Authors
Frederick Stumm, Anthony Chu, Michael D. Como, Michael L. Noll
Hydrogeologic and Geochemical Assessment of the Effects of Leakage from the Catskill and Delaware Aqueducts on the Local Bedrock and Overburden Aquifers in Southeastern New York
PROBLEM As part of an effort to sustain a viable water-supply system for 8 million residents in New York City, and 1 million other residents in upstate New York that rely on City water, the New York City Department of Environmental Protection (NYCDEP) has requested a multi-disciplinary study by the U.S. Geological Survey (USGS) to determine the source(s) of water to surface-water sites (springs
Hydrogeology and Water Quality of the North Shore Aquifer in Locust Valley, Town of Oyster Bay, New York
Problem Perchlorate detected in a shallow supply well within the southern portion of the Locust Valley Water District (LVWD) has prompted interest in determining the possible existence of a deeper confined aquifer (North Shore Aquifer) that may be protected from shallow contamination (fig. 1). Previous USGS studies in this area indicate the northern part of Nassau County has a complex hydrogeolog
Documenting Hydrogeologic Information Obtained from Deep-Borehole Drilling in Suffolk County, New York
Background Borehole drilling and well-installation are costly procedures, and securing funding for new well installation for the sake of research is often difficult.The Suffolk County Water Authority (SCWA) maintains a large network of deep wells for public supply that is constantly being upgraded as water demands increase. During the drilling process, contractors record drillers’ lo
Using Advanced Borehole Geophysical Methods to Characterize Fractures, Foliation, and Fractured-Rock Groundwater Flow at a Geothermal Test Site on Roosevelt Island, New York County, New York
Background The U.S. Geological Survey (USGS) has characterized fractures, foliation, and fractured-rock groundwater flow penetrated by test boreholes in crystalline bedrock underlying Manhattan Island, New York County, New York since 1998. New test boreholes will be drilled on Roosevelt Island in New York County for a Cornell University geothermal test project. Cornell University is partnering w
Delineation of Groundwater Flow, Lithology, Faults, and Fractures Along Existing and Proposed Water Tunnel
Problem The New York City Department of Environmental Protection (NYCDEP) has asked the U.S. Geological Survey (USGS) to assist in two major studies: 1) delineation of the source(s) of shallow groundwater and the extent that the Delaware Aqueduct is contributing to local flooding issues, and 2) delineation of the structural, geologic, and hydrologic conditions along proposed tunnel construction
Delineation of Rock Fractures, Faults, and Groundwater Flow in the Vicinity of Proposed Water Tunnels, New York City and Southeastern New York
Problem - The New York City Department of Environmental Protection (NYCDEP) is constructing or proposing water tunnels under New York City and areas of southeastern New York (Hudson River Basin). These tunnels can intersect faults and fractures that produce large amounts of ground water. For example, one tunnel excavation intersected fractures that produced over 200 gallons per minute of groun
Three-Dimensional Point Cloud Data Collected with a Scanning Total Station on the Western Shoreline of the Shinnecock Nation Tribal Lands, Suffolk County, New York, 2022
This data release contains about 60 million point cloud data points collected during 27 scans of a section of the western shoreline of the Shinnecock Peninsula in Suffolk County, New York. Data were collected during July and October of 2022. Data are provided as .las files with points classified as either bare earth (GROUND_SN_BRIC_BL_2022_v03.0 (2).las), vegetation (VEGETATION_SN_BRIC_BL_2022_v
Potentiometric-Surface Contours in a Bedrock Aquifer near High Falls, New York, 2019–2020
This geospatial data set contains groundwater level contours, well locations, and associated metadata that characterize the potentiometric surface near the Rondout pressure-tunnel in High Falls, New York during November 5–7, 2019, and January 21–22, 2020. The pressure tunnel was shut down and partially dewatered for 74 days from November 11, 2019, to January 23, 2020, for inspection and repairs.
Science and Products
Filter Total Items: 23
Accuracy assessment of three-dimensional point cloud data collected with a scanning total station on Shinnecock Nation Tribal lands in Suffolk County, New York
A combined point cloud of about 85.6 million points was collected during 27 scans of a section of the western shoreline along the Shinnecock Peninsula of Suffolk County, New York, to document baseline geospatial conditions during July and October 2022 using a scanning total station. The three-dimensional accuracy of the combined point cloud is assessed to identify potential systematic error source
Authors
Michael L. Noll, William D. Capurso, Anthony Chu
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 local groun
Authors
Anthony Chu, Michael L. Noll, William D. Capurso, Robert J. Welk
Hydrologic effects of leakage from the Catskill Aqueduct on the bedrock-aquifer system near High Falls, New York, November 2019–January 2020
Historical observations by the New York City Department of Environmental Protection (NYCDEP) indicate that the Rondout pressure tunnel has been leaking in the vicinity of the hamlet of High Falls, New York. In the 74 days from November 11, 2019, to January 23, 2020, NYCDEP shut down and partially dewatered the pressure tunnel for inspection and repairs. On November 5–7, 2019 (during normal tunnel
Authors
Anthony Chu, Michael L. Noll, William D. Capurso
Slug-test analysis of selected wells at an earthen dam site in southern Westchester County, New York
In 2005, the U.S. Geological Survey began a cooperative study with the New York City Department of Environmental Protection to characterize the local groundwater-flow system and identify potential sources of seeps on the southern embankment of the Hillview Reservoir in southern Westchester County, New York. The earthen embankment comprises low-permeability glacial clays that were excavated from th
Authors
Michael L. Noll, Anthony Chu, William D. Capurso
Groundwater-level data from an earthen dam site in southern Westchester County, New York
In 2005, the U.S. Geological Survey began a cooperative study with New York City Department of Environmental Protection to characterize the local groundwater-flow system and identify potential sources of seeps on the southern embankment of the Hillview Reservoir in Westchester County, New York. Groundwater levels were collected at 49 wells at Hillview Reservoir, and 1 well in northern Bronx County
Authors
Michael L. Noll, Anthony Chu
Water-quality data from an earthen dam site in southern Westchester County, New York, 2015
The U.S. Geological Survey, in cooperation with the New York City Department of Environmental Protection, sampled 37 sites in the reservoir area for nutrients, major ions, metals, pesticides and their degradates, volatile organic compounds, temperature, pH, and specific conductance during fall 2015. Data collection was done to characterize the local groundwater-flow system and identify potential s
Authors
Anthony Chu, Michael L. Noll
Detecting temporal change in land-surface altitude using robotic land-surveying techniques and geographic information system applications at an earthen dam site in Southern Westchester County, New York
In 2005, the U.S. Geological Survey began a cooperative study with New York City Department of Environmental Protection to characterize the local groundwater-flow system and identify potential sources of seeps on the southern embankment at the Hillview Reservoir in southern Westchester County, New York. Monthly site inspections at the reservoir indicated an approximately 90-square-foot depression
Authors
Michael L. Noll, Anthony Chu
Delineation of fractures, foliation, and groundwater of the bedrock at a geothermal feasibility site on Roosevelt Island, New York County, New York
Advanced borehole-geophysical methods were used to investigate the hydrogeology of the crystalline bedrock in three boreholes on Roosevelt Island, New York County, New York. Cornell University was evaluating the feasibility of using geothermal energy for a future campus at the site. The borehole-logging techniques were used to delineate bedrock fractures, foliation, and groundwater-flow zones of t
Authors
Frederick Stumm, Anthony Chu, Michael D. Como, Michael L. Noll, Peter K. Joesten
Delineation of fractures, foliation, and groundwater-flow zones of the bedrock at the Harlem River Tunnel in northern New York County, New York
Advanced borehole-geophysical methods were used to investigate the hydrogeology of the crystalline bedrock in 36 boreholes on the northernmost part of New York County, New York, for the construction of a utilities tunnel beneath the Harlem River. The borehole-logging techniques were used to delineate bedrock fractures, foliation, and groundwater-flow zones in test boreholes at the site. Fracture i
Authors
Frederick Stumm, Anthony Chu, Peter K. Joesten, Michael L. Noll, Michael D. Como
Geophysical and hydrologic analysis of an earthen dam site in southern Westchester County, New York
Ninety percent of the drinking water for New York City passes through the Hillview Reservoir facility in the City of Yonkers, Westchester County, New York. In the past, several seeps located downslope from the reservoir have flowed out from the side of the steepest slope at the southern end of the earthen embankment. One seep that has been flowing continuously was discovered during an inspection o
Authors
Anthony Chu, Frederick Stumm, Peter K. Joesten, Michael L. Noll
Preliminary assessment of water chemistry related to groundwater flooding in Wawarsing, New York, 2009-11
Water-quality samples collected in an area prone to groundwater flooding in Wawarsing, New York, were analyzed and assessed to better understand the hydrologic system and to aid in the assessment of contributing water sources. Above average rainfall over the past decade, and the presence of a pressurized water tunnel that passes about 700 feet beneath Wawarsing, could both contribute to groundwate
Authors
Craig J. Brown, David A. Eckhardt, Frederick Stumm, Anthony Chu
Preliminary analysis of the hydrologic effects of temporary shutdowns of the Rondout-West Branch Water Tunnel on the groundwater-flow system in Wawarsing, New York
Flooding of streets and residential basements, and bacterial contamination of private-supply wells with Escherichia coli (E. coli) are recurring problems in the Rondout Valley near the Town of Wawarsing, Ulster County, New York. Leakage from the Rondout-West Branch (RWB) Water Tunnel and above-normal precipitation have been suspected of causing elevated groundwater levels and basement flooding. Th
Authors
Frederick Stumm, Anthony Chu, Michael D. Como, Michael L. Noll
Hydrogeologic and Geochemical Assessment of the Effects of Leakage from the Catskill and Delaware Aqueducts on the Local Bedrock and Overburden Aquifers in Southeastern New York
PROBLEM As part of an effort to sustain a viable water-supply system for 8 million residents in New York City, and 1 million other residents in upstate New York that rely on City water, the New York City Department of Environmental Protection (NYCDEP) has requested a multi-disciplinary study by the U.S. Geological Survey (USGS) to determine the source(s) of water to surface-water sites (springs
Hydrogeology and Water Quality of the North Shore Aquifer in Locust Valley, Town of Oyster Bay, New York
Problem Perchlorate detected in a shallow supply well within the southern portion of the Locust Valley Water District (LVWD) has prompted interest in determining the possible existence of a deeper confined aquifer (North Shore Aquifer) that may be protected from shallow contamination (fig. 1). Previous USGS studies in this area indicate the northern part of Nassau County has a complex hydrogeolog
Documenting Hydrogeologic Information Obtained from Deep-Borehole Drilling in Suffolk County, New York
Background Borehole drilling and well-installation are costly procedures, and securing funding for new well installation for the sake of research is often difficult.The Suffolk County Water Authority (SCWA) maintains a large network of deep wells for public supply that is constantly being upgraded as water demands increase. During the drilling process, contractors record drillers’ lo
Using Advanced Borehole Geophysical Methods to Characterize Fractures, Foliation, and Fractured-Rock Groundwater Flow at a Geothermal Test Site on Roosevelt Island, New York County, New York
Background The U.S. Geological Survey (USGS) has characterized fractures, foliation, and fractured-rock groundwater flow penetrated by test boreholes in crystalline bedrock underlying Manhattan Island, New York County, New York since 1998. New test boreholes will be drilled on Roosevelt Island in New York County for a Cornell University geothermal test project. Cornell University is partnering w
Delineation of Groundwater Flow, Lithology, Faults, and Fractures Along Existing and Proposed Water Tunnel
Problem The New York City Department of Environmental Protection (NYCDEP) has asked the U.S. Geological Survey (USGS) to assist in two major studies: 1) delineation of the source(s) of shallow groundwater and the extent that the Delaware Aqueduct is contributing to local flooding issues, and 2) delineation of the structural, geologic, and hydrologic conditions along proposed tunnel construction
Delineation of Rock Fractures, Faults, and Groundwater Flow in the Vicinity of Proposed Water Tunnels, New York City and Southeastern New York
Problem - The New York City Department of Environmental Protection (NYCDEP) is constructing or proposing water tunnels under New York City and areas of southeastern New York (Hudson River Basin). These tunnels can intersect faults and fractures that produce large amounts of ground water. For example, one tunnel excavation intersected fractures that produced over 200 gallons per minute of groun
Three-Dimensional Point Cloud Data Collected with a Scanning Total Station on the Western Shoreline of the Shinnecock Nation Tribal Lands, Suffolk County, New York, 2022
This data release contains about 60 million point cloud data points collected during 27 scans of a section of the western shoreline of the Shinnecock Peninsula in Suffolk County, New York. Data were collected during July and October of 2022. Data are provided as .las files with points classified as either bare earth (GROUND_SN_BRIC_BL_2022_v03.0 (2).las), vegetation (VEGETATION_SN_BRIC_BL_2022_v
Potentiometric-Surface Contours in a Bedrock Aquifer near High Falls, New York, 2019–2020
This geospatial data set contains groundwater level contours, well locations, and associated metadata that characterize the potentiometric surface near the Rondout pressure-tunnel in High Falls, New York during November 5–7, 2019, and January 21–22, 2020. The pressure tunnel was shut down and partially dewatered for 74 days from November 11, 2019, to January 23, 2020, for inspection and repairs.