Hydrologist of the Hydrologic Remote Sensing Branch of the USGS Water Mission Area, operates Time-domain electromagnetic (TDEM) equipment in Chilmark, Massachusetts.
Timothy D McCobb
Tim McCobb is a Hydrologist in the USGS New England Water Science Center.
Tim has experience working on groundwater projects in southeastern Massachusetts, including research at the USGS Cape Cod Toxic Substances Hydrology field site and technical support of Dept. of Defense environmental restoration programs at Joint Base Cape Cod. He has extensive experience in groundwater field techniques, groundwater flow modeling, and GIS. Tim is currently working on projects that include the assessment of regional freshwater resources by using groundwater modeling, the examination of nitrogen and emerging contaminants in shallow, coastal groundwater, and the characterization of groundwater/surface-water interactions at a glacial kettle pond.
Professional Experience
Hydrologist, U.S. Geological Survey, New England Water Science Center, 1991 to Present
Education and Certifications
B.S. Civil Engineering, Northeastern University, 1995
Science and Products
Effects of Sea-Level Rise and Climate Change on the Groundwater-Flow System of Martha’s Vineyard, Massachusetts
Assessment of Nutrient Transport and Discharge to Coastal Embayments, Wickford, Rhode Island
Measurement and Modeling of Nitrogen Discharge to Cape Cod Rivers to Identify High-Priority Nitrogen Reduction Areas
Hydrologic Monitoring in the Three Bays Watershed in Support of Nutrient Management Activities, Cape Cod, Massachusetts
Assessment of Potential Effects of Water-Supply Withdrawals on Groundwater Levels near the Hyannis Ponds Complex, Barnstable, Massachusetts
Hydrologic Site Assessment for Passive Treatment of Groundwater Nitrogen with Permeable Reactive Barriers, Cape Cod, Massachusetts
USGS Publications on the Water Resources of Cape Cod and Southeastern Massachusetts
Assessment of Hydrologic and Water-Quality Changes in Shallow Groundwater Beneath a Coastal Neighborhood Being Converted from Septic Systems to Municipal Sewers
Water-Quality Data in and near Groundwater Flow-Through Kettle-Hole Lakes, Western Cape Cod, Massachusetts, 2003 - 2018
Lakebed Groundwater and Surface-Water Temperatures on September 18, 2020, at Shubael Pond, Marstons Mills, Massachusetts
Baseline Groundwater-Quality Data from a Densely Developed Coastal Neighborhood, Falmouth, Massachusetts (2016 - 2021)(ver. 4.0, February 2022)
QUASHNET SPAWN HESS CHEMICAL DATA
Geochemical data supporting analysis of fate and transport of nitrogen in the near shore groundwater and subterranean estuary near East Falmouth, Massachusetts, 2015
Chemical Data From 40 Years of Monitoring a Treated-Wastewater Groundwater Plume in a Sand and Gravel Aquifer, Cape Cod, Massachusetts, 1978-2018
Microbial Community and N-cycling gene abundance from Ponds and Groundwater on Cape Cod, MA (2015 - 2018)
Seasonal and spatial variation in the location and reactivity of a nitrate-contaminated groundwater discharge zone in a lakebed
Data Release for Lake Shadow Seepage Calculations from Ashumet Pond, Cape Cod, MA, 2016 - 2018
Geochemical data supporting analysis of geochemical conditions and nitrogen transport in nearshore groundwater and the subterranean estuary at a Cape Cod embayment, East Falmouth, Massachusetts
Temperature and seepage data from a lake-bottom permeable reactive barrier, Ashumet Pond, Falmouth, MA, 2004-2015.
Hydrologist of the Hydrologic Remote Sensing Branch of the USGS Water Mission Area, operates Time-domain electromagnetic (TDEM) equipment in Chilmark, Massachusetts.
Maddy Holland (New England Water Science Center), Eric White (Water Mission Area - Hydrologic Remote Sensing Branch), Jason Sorenson (New England Water Science Center), and Carole Johnson (Water Mission Area - Hydrologic Remote Sensing Branch) moving heavy TDEM field gear across a field in Edgartown, Massachusetts.
Maddy Holland (New England Water Science Center), Eric White (Water Mission Area - Hydrologic Remote Sensing Branch), Jason Sorenson (New England Water Science Center), and Carole Johnson (Water Mission Area - Hydrologic Remote Sensing Branch) moving heavy TDEM field gear across a field in Edgartown, Massachusetts.
Gay Head Lighthouse and Aquinnah Cliffs, Aquinnah, Martha's Vineyard, Massachusetts.
Gay Head Lighthouse and Aquinnah Cliffs, Aquinnah, Martha's Vineyard, Massachusetts.
Edgartown Lighthouse looking northwest toward Edgartown, Martha's Vineyard, Massachusetts.
Edgartown Lighthouse looking northwest toward Edgartown, Martha's Vineyard, Massachusetts.
American beachgrass planted near South Beach in Edgartown, MA (looking east) during sunrise.
American beachgrass planted near South Beach in Edgartown, MA (looking east) during sunrise.
South Beach looking west at sunset in Edgartown, Martha's Vineyard, Massachusetts.
South Beach looking west at sunset in Edgartown, Martha's Vineyard, Massachusetts.
Deer grazing in a hayfield during the evening on farmland in Chilmark, Massachusetts.
Deer grazing in a hayfield during the evening on farmland in Chilmark, Massachusetts.
The USGS is conducting a study to characterize groundwater and surface water-quality to address the need for a better understanding of nutrient inputs to the coastal waters. The initial focus of the study is on local-scale hydrologic monitoring adjacent to Academy Cove.
The USGS is conducting a study to characterize groundwater and surface water-quality to address the need for a better understanding of nutrient inputs to the coastal waters. The initial focus of the study is on local-scale hydrologic monitoring adjacent to Academy Cove.
Streamgage location (0110588340) on the Santuit River at Old Kings Road, Barnstable MA.
Streamgage location (0110588340) on the Santuit River at Old Kings Road, Barnstable MA.
Drillers from the Environmental Protection Agency Office of Research and Development (Ada, OK) using a sonic drilling rig to install monitoring wells in Barnstable, Massachusetts.
Drillers from the Environmental Protection Agency Office of Research and Development (Ada, OK) using a sonic drilling rig to install monitoring wells in Barnstable, Massachusetts.
Monitoring wells located along the eastern shore of Little Pond, East Falmouth, Massachusetts.
Monitoring wells located along the eastern shore of Little Pond, East Falmouth, Massachusetts.
Groundwater sampling along the eastern shore of Little Pond, East Falmouth, Massachusetts.
Groundwater sampling along the eastern shore of Little Pond, East Falmouth, Massachusetts.
Groundwater sampling along the western shore of Great Pond, East Falmouth, Massachusetts.
Groundwater sampling along the western shore of Great Pond, East Falmouth, Massachusetts.
Eutrophication is seen along the eastern shore of Little Pond, East Falmouth, Massachusetts.
Eutrophication is seen along the eastern shore of Little Pond, East Falmouth, Massachusetts.
Eutrophication seen on the eastern shore of Little Pond, East Falmouth, Massachusetts.
Eutrophication seen on the eastern shore of Little Pond, East Falmouth, Massachusetts.
Well installation using a Geoprobe drilling rig in the Maravista neighborhood, East Falmouth, MA
Well installation using a Geoprobe drilling rig in the Maravista neighborhood, East Falmouth, MA
Evaluating the effects of replacing septic systems with municipal sewers on groundwater quality in a densely developed coastal neighborhood, Falmouth, Massachusetts, 2016–19
Simulated water-table and pond-level responses to proposed public water-supply withdrawals in the Hyannis Ponds Wildlife Management Area, Barnstable, Massachusetts
Lithostratigraphic, geophysical, and hydrogeologic observations from a boring drilled to bedrock in glacial sediments near Nantucket Sound in East Falmouth, Massachusetts
Use of a Numerical Model to Simulate the Hydrologic System and Transport of Contaminants Near Joint Base Cape Cod, Western Cape Cod, Massachusetts
Hydrogeochemical controls on brook trout spawning habitats in a coastal stream
Geochemical conditions and nitrogen transport in nearshore groundwater and the subterranean estuary at a Cape Cod embayment, East Falmouth, Massachusetts, 2013–14
Evaluating long-term patterns of decreasing groundwater discharge through a lake-bottom permeable reactive barrier
Potential effects of sea-level rise on the depth to saturated sediments of the Sagamore and Monomoy flow lenses on Cape Cod, Massachusetts
Hydrologic controls on nitrogen cycling processes and functional gene abundance in sediments of a groundwater flow-through lake
Importance of the colmation layer in the transport and removal of cyanobacteria, viruses, and dissolved organic carbon during natural lake-bank filtration
Hydrologic, vegetation, and soil data collected in selected wetlands of the Big River Management area, Rhode Island, from 2008 through 2010
Water-quality data from shallow pond-bottom groundwater in the Fishermans Cove area of Ashumet Pond, Cape Cod, Massachusetts, 2001-2010
Science and Products
- Science
Effects of Sea-Level Rise and Climate Change on the Groundwater-Flow System of Martha’s Vineyard, Massachusetts
The U.S. Geological Survey (USGS), in cooperation with the Massachusetts Department of Environmental Protection (MassDEP), is investigating the effects of sea-level rise and climate change on the groundwater resources of Martha’s Vineyard, Massachusetts.Assessment of Nutrient Transport and Discharge to Coastal Embayments, Wickford, Rhode Island
In 2020 the USGS began a partnership with the U.S. Environmental Protection Agency (EPA) Region 1 Southeast New England Program for Coastal Watershed Restoration (SNEP) and EPA Office of Research and Development (ORD), Atlantic Coastal Sciences Division, Narragansett, RI in support of water-quality and ecological monitoring being conducted by ORD in the coastal waters around Wickford, RI. The USGS...Measurement and Modeling of Nitrogen Discharge to Cape Cod Rivers to Identify High-Priority Nitrogen Reduction Areas
In 2019 USGS and the U.S. Environmental Protection Agency (EPA) Region 1 initiated a study to measure spatial and temporal patterns of nitrogen loading in selected rivers on Cape Cod and then determine whether the measured patterns can be related to nitrogen source areas in the surrounding watersheds to prioritize nitrogen reduction efforts. Study results will improve understanding of nitrogen...Hydrologic Monitoring in the Three Bays Watershed in Support of Nutrient Management Activities, Cape Cod, Massachusetts
In 2019 the USGS began a partnership with the U.S. Environmental Protection Agency (EPA) Office of Research and Development (ORD), EPA Region 1 Southeast New England Program for Coastal Watershed Restoration (SNEP), Barnstable Clean Water Coalition (BCWC), and other stakeholders to conduct hydrologic monitoring and assessment in support of multifaceted nutrient-management activities in the Three...Assessment of Potential Effects of Water-Supply Withdrawals on Groundwater Levels near the Hyannis Ponds Complex, Barnstable, Massachusetts
The USGS, in cooperation with the Town of Barnstable and MassWildlife, is assessing the potential effects of new water-supply withdrawals on groundwater levels in the Hyannis Ponds Wildlife Management Area on Cape Cod. A groundwater-flow model is being used to simulate the effects of several possible withdrawal and wastewater-return flow scenarios developed by the Town of Barnstable and...Hydrologic Site Assessment for Passive Treatment of Groundwater Nitrogen with Permeable Reactive Barriers, Cape Cod, Massachusetts
In 2019 USGS completed a study designed to develop and evaluate a phased site-assessment approach for determining the hydrologic suitability of sites being considered for permeable reactive barrier installation on Cape Cod. The approach provides a template for town officials and other stakeholders to follow when considering PRBs for passive treatment of nitrogen in groundwater on Cape Cod and...USGS Publications on the Water Resources of Cape Cod and Southeastern Massachusetts
The U.S. Geological Survey (USGS) has been investigating groundwater and surface-water resources on Cape Cod for more than 50 years. Recent studies have focused on the sources of water to public-supply wells, ponds, streams, and coastal areas; transport and discharge of nitrogen and contaminants of emerging concern derived from domestic and municipal wastewater disposal; fate and transport of...Assessment of Hydrologic and Water-Quality Changes in Shallow Groundwater Beneath a Coastal Neighborhood Being Converted from Septic Systems to Municipal Sewers
The U.S. Geological Survey and the U.S. Environmental Protection Agency are collaborating on a study to better understand changes to groundwater quality beneath a densely developed coastal neighborhood as it undergoes conversion from onsite wastewater disposal to municipal sewering. - Data
Water-Quality Data in and near Groundwater Flow-Through Kettle-Hole Lakes, Western Cape Cod, Massachusetts, 2003 - 2018
This U.S. Geological Survey (USGS) data release provides a comprehensive dataset of water-quality results, physical-parameter measurements, hydrologic measurements, and site information collected to study the nature and extent of water quality along groundwater flow paths adjacent to glacial-kettle lakes on Cape Cod, Massachusetts. Water-quality samples were collected in 2003, 2005, and 2012 throLakebed Groundwater and Surface-Water Temperatures on September 18, 2020, at Shubael Pond, Marstons Mills, Massachusetts
This data release contains lakebed groundwater and surface-water temperatures collected during a survey on September 18, 2020, by using a handheld thermocouple probe at Shubael Pond, a groundwater flow-through kettle-hole pond, located in Marstons Mills, Massachusetts. The dataset includes a comma separated values (.csv) file, a geospatial dataset (shapefile), and FGDC-compliant metadata.Baseline Groundwater-Quality Data from a Densely Developed Coastal Neighborhood, Falmouth, Massachusetts (2016 - 2021)(ver. 4.0, February 2022)
This data release provides a comprehensive dataset of sampling-site characteristics and baseline groundwater-quality data collected from a network of multilevel sampling wells installed in a densely developed coastal neighborhood undergoing a conversion from onsite septic systems to municipal sewering. Groundwater samples were collected during multiple events from a total of 227 well screens at 15QUASHNET SPAWN HESS CHEMICAL DATA
This data set includes dissolved oxygen (DO) and specific conductivity (SpC) data collected in both the surface water and shallow streambed at the Quashnet River, Mashpee, USA from 2014-16. This data was collected to better understand groundwater discharge to the river and associated brook trout habitat. DO was typically near saturation in surface water and some groundwater, but is reduced in streGeochemical data supporting analysis of fate and transport of nitrogen in the near shore groundwater and subterranean estuary near East Falmouth, Massachusetts, 2015
Geochemical data were obtained to investigate the fate and transport of nitrogen in a subterranean estuary near East Falmouth, Massachusetts. The goal of this investigation was to assess nitrogen attenuation in the aquifer under the Eel River Estuary and the adjacent peninsula that was densely populated with residences having septic systems and legacy cesspool inputs of inorganic nitrogen. This esChemical Data From 40 Years of Monitoring a Treated-Wastewater Groundwater Plume in a Sand and Gravel Aquifer, Cape Cod, Massachusetts, 1978-2018
This U.S. Geological Survey data release provides a comprehensive dataset of water-quality data and sampling-site characteristics collected in 1978-2018 during a study of the effects of land disposal of treated wastewater on groundwater quality in an unconsolidated sand and gravel aquifer on Cape Cod, Massachusetts. Treated sewage-derived wastewater was discharged to rapid-infiltration beds at JoiMicrobial Community and N-cycling gene abundance from Ponds and Groundwater on Cape Cod, MA (2015 - 2018)
Surface water, pore water, pond bottom sediments, and groundwater were sampled within and downgradient from five groundwater flow-through ponds that ranged from oligotrophic to eutrophic in Cape Cod, Massachusetts during different seasons from 2015 – 2018. The sampled ponds included Ashumet, Santuit, Snake, Shubael, and Longs. Pore water was collected between 15 to 100 cm below the pond bottoms onSeasonal and spatial variation in the location and reactivity of a nitrate-contaminated groundwater discharge zone in a lakebed
The U.S. Geological Survey Toxic Substances Hydrology Program at Cape Cod has been investigating the fate and transport of a treated-wastewater, groundwater contaminant plume. A portion of the contaminated groundwater discharges into Ashumet Pond, a kettle hole, freshwater lake. A study was conducted from June 2013 to June 2015 to document transport, transformation, and discharge of dissolved inorData Release for Lake Shadow Seepage Calculations from Ashumet Pond, Cape Cod, MA, 2016 - 2018
Hydrologic data were collected in the nearshore lake-bottom sediments of five lakes on western Cape Cod, Massachusetts: Ashumet (Falmouth), Long (Centerville), Santuit (Mashpee), Shubael (Barnstable), and Snake (Sandwich) Ponds. Water budgets of flow-through glacial kettle lakes are commonly dominated by groundwater flow into and surface-water seepage out of the lake, and inputs and losses from prGeochemical data supporting analysis of geochemical conditions and nitrogen transport in nearshore groundwater and the subterranean estuary at a Cape Cod embayment, East Falmouth, Massachusetts
This data release provides analytical and other data in support of an analysis of nitrogen transport and transformation in groundwater and in a subterranean estuary in the Eel River and onshore locations on the Seacoast Shores peninsula, Falmouth, Massachusetts. The analysis is described in U.S. Geological Survey Scientific Investigations Report 2018-5095 by Colman and others (2018). This data relTemperature and seepage data from a lake-bottom permeable reactive barrier, Ashumet Pond, Falmouth, MA, 2004-2015.
These data were collected to evaluate groundwater/surface-water exchange in the area of a lake-bottom permeable reactive barrier and to assess changes in groundwater seepage over the period between 2004 and 2015. This data release includes geospatial datasets, comma separated values (.csv) files, and associated FGDC-compliant metadata representing data collected between 2004 and 2015 as part of a - Maps
- Multimedia
Hydrologist operates Time Domain Electromagnetic equipment on Martha's VineyardHydrologist operates Time Domain Electromagnetic equipment on Martha's Vineyard
Hydrologist of the Hydrologic Remote Sensing Branch of the USGS Water Mission Area, operates Time-domain electromagnetic (TDEM) equipment in Chilmark, Massachusetts.
Hydrologist of the Hydrologic Remote Sensing Branch of the USGS Water Mission Area, operates Time-domain electromagnetic (TDEM) equipment in Chilmark, Massachusetts.
Hydrologists with TDEM EquipmentMaddy Holland (New England Water Science Center), Eric White (Water Mission Area - Hydrologic Remote Sensing Branch), Jason Sorenson (New England Water Science Center), and Carole Johnson (Water Mission Area - Hydrologic Remote Sensing Branch) moving heavy TDEM field gear across a field in Edgartown, Massachusetts.
Maddy Holland (New England Water Science Center), Eric White (Water Mission Area - Hydrologic Remote Sensing Branch), Jason Sorenson (New England Water Science Center), and Carole Johnson (Water Mission Area - Hydrologic Remote Sensing Branch) moving heavy TDEM field gear across a field in Edgartown, Massachusetts.
Gay Head Lighthouse, Aquinnah, MassachusettsGay Head Lighthouse and Aquinnah Cliffs, Aquinnah, Martha's Vineyard, Massachusetts.
Gay Head Lighthouse and Aquinnah Cliffs, Aquinnah, Martha's Vineyard, Massachusetts.
Lighthouse in Edgartown, MassachusettsEdgartown Lighthouse looking northwest toward Edgartown, Martha's Vineyard, Massachusetts.
Edgartown Lighthouse looking northwest toward Edgartown, Martha's Vineyard, Massachusetts.
American beachgrass planted near South Beach in Edgartown, MassachusettsAmerican beachgrass planted near South Beach in Edgartown, MassachusettsAmerican beachgrass planted near South Beach in Edgartown, MA (looking east) during sunrise.
American beachgrass planted near South Beach in Edgartown, MA (looking east) during sunrise.
South Beach, Edgartown, MassachusettsSouth Beach looking west at sunset in Edgartown, Martha's Vineyard, Massachusetts.
South Beach looking west at sunset in Edgartown, Martha's Vineyard, Massachusetts.
Farmland in Chilmark, MassachusettsDeer grazing in a hayfield during the evening on farmland in Chilmark, Massachusetts.
Deer grazing in a hayfield during the evening on farmland in Chilmark, Massachusetts.
Academy Cove, Wickford, Rhode IslandThe USGS is conducting a study to characterize groundwater and surface water-quality to address the need for a better understanding of nutrient inputs to the coastal waters. The initial focus of the study is on local-scale hydrologic monitoring adjacent to Academy Cove.
The USGS is conducting a study to characterize groundwater and surface water-quality to address the need for a better understanding of nutrient inputs to the coastal waters. The initial focus of the study is on local-scale hydrologic monitoring adjacent to Academy Cove.
Streamgage 0110588340 Barnstable, MAStreamgage location (0110588340) on the Santuit River at Old Kings Road, Barnstable MA.
Streamgage location (0110588340) on the Santuit River at Old Kings Road, Barnstable MA.
Drillers using a sonic drilling rig to install monitoring wellsDrillers using a sonic drilling rig to install monitoring wellsDrillers from the Environmental Protection Agency Office of Research and Development (Ada, OK) using a sonic drilling rig to install monitoring wells in Barnstable, Massachusetts.
Drillers from the Environmental Protection Agency Office of Research and Development (Ada, OK) using a sonic drilling rig to install monitoring wells in Barnstable, Massachusetts.
Monitoring wells East Falmouth, MAMonitoring wells located along the eastern shore of Little Pond, East Falmouth, Massachusetts.
Monitoring wells located along the eastern shore of Little Pond, East Falmouth, Massachusetts.
Groundwater samplingGroundwater sampling along the eastern shore of Little Pond, East Falmouth, Massachusetts.
Groundwater sampling along the eastern shore of Little Pond, East Falmouth, Massachusetts.
Groundwater samplingGroundwater sampling along the western shore of Great Pond, East Falmouth, Massachusetts.
Groundwater sampling along the western shore of Great Pond, East Falmouth, Massachusetts.
View along the eastern shore of Little Pond, East FalmouthView along the eastern shore of Little Pond, East FalmouthEutrophication is seen along the eastern shore of Little Pond, East Falmouth, Massachusetts.
Eutrophication is seen along the eastern shore of Little Pond, East Falmouth, Massachusetts.
View of the eastern shore of Little Pond, East Falmouth, MAView of the eastern shore of Little Pond, East Falmouth, MAEutrophication seen on the eastern shore of Little Pond, East Falmouth, Massachusetts.
Eutrophication seen on the eastern shore of Little Pond, East Falmouth, Massachusetts.
Well installation using a Geoprobe drilling rigWell installation using a Geoprobe drilling rig in the Maravista neighborhood, East Falmouth, MA
Well installation using a Geoprobe drilling rig in the Maravista neighborhood, East Falmouth, MA
- Publications
Filter Total Items: 20
Evaluating the effects of replacing septic systems with municipal sewers on groundwater quality in a densely developed coastal neighborhood, Falmouth, Massachusetts, 2016–19
Land disposal of sewage wastewater through septic systems and cesspools is a major cause of elevated concentrations of nitrogen in the shallow coastal aquifers of southern New England. The discharge of nitrogen from these sources at the coast is affecting the environmental health of coastal saltwater bodies. In response, local, State, and Federal agencies are considering expensive actions to mitigAuthorsTimothy D. McCobb, Jeffrey R. Barbaro, Denis R. LeBlanc, Marcel BelavalSimulated water-table and pond-level responses to proposed public water-supply withdrawals in the Hyannis Ponds Wildlife Management Area, Barnstable, Massachusetts
The glacial kettle ponds in the Hyannis Ponds Wildlife Management Area in Barnstable, Massachusetts, support a community of rare and endangered plants. The ponds are hydraulically connected to the unconfined aquifer that underlies Cape Cod. The plants are adapted to the rise and fall of water levels in the ponds as the water table fluctuates in response to seasonal and year-to-year natural changesAuthorsDenis R. LeBlanc, Timothy D. McCobb, Jeffrey R. BarbaroLithostratigraphic, geophysical, and hydrogeologic observations from a boring drilled to bedrock in glacial sediments near Nantucket Sound in East Falmouth, Massachusetts
In spring 2016, a 310-foot-deep boring (named MA–FSW 750) was drilled by the U.S. Geological Survey near Nantucket Sound in East Falmouth, Massachusetts, to investigate the hydrogeology of the southern coast of western Cape Cod. Few borings that are drilled to bedrock exist in the area, and the study area was selected to fill a gap between comprehensive geologic datasets inland to the north and maAuthorsRobert B. Hull, Carole D. Johnson, Byron D. Stone, Denis R. LeBlanc, Timothy D. McCobb, Stephanie N. Phillips, Katherine L. Pappas, John W. LaneUse of a Numerical Model to Simulate the Hydrologic System and Transport of Contaminants Near Joint Base Cape Cod, Western Cape Cod, Massachusetts
Historical training and operational activities at Joint Base Cape Cod (JBCC) on western Cape Cod, Massachusetts, have resulted in the release of contaminants into an underlying glacial aquifer that is the sole source of water to the surrounding communities. Remedial systems have been installed to contain and remove contamination from the aquifer. Groundwater withdrawals for public supply are expecAuthorsDonald A. Walter, Timothy D. McCobb, Michael N. FienenHydrogeochemical controls on brook trout spawning habitats in a coastal stream
Brook trout (Salvelinus fontinalis) spawn in fall and overwintering egg development can benefit from stable, relatively warm temperatures in groundwater-seepage zones. However, eggs are also sensitive to dissolved oxygen concentration, which may be reduced in discharging groundwater (i.e., seepage). We investigated a 2 km reach of the coastal Quashnet River in Cape Cod, Massachusetts, USA, to relaAuthorsMartin A. Briggs, Judson W. Harvey, Stephen T. Hurley, Donald O. Rosenberry, Timothy D. McCobb, Dale D. Werkema, John W. LaneGeochemical conditions and nitrogen transport in nearshore groundwater and the subterranean estuary at a Cape Cod embayment, East Falmouth, Massachusetts, 2013–14
Nitrogen transport and transformation were studied during 2013 to 2014 by the U.S. Geological Survey, in cooperation with the U.S. Environmental Protection Agency, in a subterranean estuary beneath onshore locations on the Seacoast Shores peninsula, a residential area in Falmouth, Massachusetts, served by septic systems and cesspools, and adjacent offshore locations in the Eel River, a saltwater eAuthorsJohn A. Colman, Denis R. LeBlanc, John K. Böhlke, Timothy D. McCobb, Kevin D. Kroeger, Marcel Belaval, Thomas C. Cambareri, Gillian F. Pirolli, T. Wallace Brooks, Mary E. Garren, Tobias B. Stover, Ann KeeleyEvaluating long-term patterns of decreasing groundwater discharge through a lake-bottom permeable reactive barrier
Identifying and quantifying groundwater exchange is critical when considering contaminant fate and transport at the groundwater/surface-water interface. In this paper, areally distributed temperature and point seepage measurements are used to efficiently assess spatial and temporal groundwater discharge patterns through a glacial-kettle lakebed area containing a zero-valent iron permeable reactiveAuthorsTimothy D. McCobb, Martin A. Briggs, Denis R. LeBlanc, Frederick D. Day-Lewis, Carole D. JohnsonPotential effects of sea-level rise on the depth to saturated sediments of the Sagamore and Monomoy flow lenses on Cape Cod, Massachusetts
In 2014, the U.S. Geological Survey, in cooperation with the Association to Preserve Cape Cod, the Cape Cod Commission, and the Massachusetts Environmental Trust, began an evaluation of the potential effects of sea-level rise on water table altitudes and depths to water on central and western Cape Cod, Massachusetts. Increases in atmospheric and oceanic temperatures arising, in part, from the releAuthorsDonald A. Walter, Timothy D. McCobb, John P. Masterson, Michael N. FienenHydrologic controls on nitrogen cycling processes and functional gene abundance in sediments of a groundwater flow-through lake
The fate and transport of inorganic nitrogen (N) is a critically important issue for human and aquatic ecosystem health because discharging N-contaminated groundwater can foul drinking water and cause algal blooms. Factors controlling N-processing were examined in sediments at three sites with contrasting hydrologic regimes at a lake on Cape Cod, MA. These factors included water chemistry, seepageAuthorsDeborah L. Stoliker, Deborah A. Repert, Richard L. Smith, Bongkeun Song, Denis R. LeBlanc, Timothy D. McCobb, Christopher Conaway, Sung Pil Hyun, Dong-Chan Koh, Hee Sun Moon, Douglas B. KentImportance of the colmation layer in the transport and removal of cyanobacteria, viruses, and dissolved organic carbon during natural lake-bank filtration
This study focused on the importance of the colmation layer in the removal of cyanobacteria, viruses, and dissolved organic carbon (DOC) during natural bank filtration. Injection-and-recovery studies were performed at two shallow (0.5 m deep), sandy, near-shore sites at the southern end of Ashumet Pond, a waste-impacted, kettle pond on Cape Cod, MA, that is subject to periodic blooms of cyanobacteAuthorsRonald W. Harvey, David W. Metge, Denis R. LeBlanc, Jennifer C. Underwood, George R. Aiken, Kenna D. Butler, Timothy D. McCobb, Jay JasperseHydrologic, vegetation, and soil data collected in selected wetlands of the Big River Management area, Rhode Island, from 2008 through 2010
The Rhode Island Water Resources Board planned to develop public water-supply wells in the Big River Management Area in Kent County, Rhode Island. Research in the United States and abroad indicates that groundwater withdrawal has the potential to affect wetland hydrology and related processes. In May 2008, the Rhode Island Water Resources Board, the U.S. Geological Survey, and the University of RhAuthorsMeredith S. Borenstein, Francis C. Golet, David S. Armstrong, Robert F. Breault, Timothy D. McCobb, Peter K. WeiskelWater-quality data from shallow pond-bottom groundwater in the Fishermans Cove area of Ashumet Pond, Cape Cod, Massachusetts, 2001-2010
The U.S. Geological Survey (USGS) collected water-quality data between 2001 and 2010 in the Fishermans Cove area of Ashumet Pond, Falmouth, Massachusetts, where the eastern portion of a treated-wastewater plume, created by more than 60 years of overland disposal, discharges to the pond. Temporary drive points were installed, and shallow pond-bottom groundwater was sampled, at 167 locations in 2001AuthorsTimothy D. McCobb, Denis R. LeBlanc - News