Elizabeth Ahearn
Elizabeth Ahearn is a Hydrologist in the New England Water Science Center.
Science and Products
Regional Regression Equations for Estimating Selected Low-flow Statistics at Ungaged Stream Sites in Massachusetts
The U.S. Geological Survey, in cooperation with the Massachusetts Department of Recreation and Conservation, Office of Water Resources, began a study in 2019 to update the regional regression equations for estimating selected low-flow statistics at ungaged sites in Massachusetts.
Developing Synthetic Historical Record at Groundwater Wells Using Record Extension Techniques
The Groundwater Index in the Massachusetts Drought Management Plan provides a general overview of groundwater levels relative to long-term groundwater levels in Massachusetts. The methods used to compute the Groundwater Index were revised for the 2019 version of the Drought Management Plan. The 2019 plan aligns the drought categories and specifies the drought status from select percentile ranges...
Development of Flood Insurance Maps in New England
FEMA has requested USGS expertise in hydraulics, hydrology, and mapping to generate flood insurance maps for New England.
Development of Regional Regression Equations in Connecticut
Knowledge of the magnitude and frequency of floods is needed for the effective and safe design of bridges, culverts, and other structures. This information is also important for flood-plain planning and management. Periodic examination of flood-frequency characteristics is essential to ensure the best estimates of flood magnitudes for a given annual exceedance probabilities (AEP).
Filter Total Items: 16
Estimating groundwater level records using MOVE.1 and computing monthly percentiles from estimated groundwater records in Massachusetts
The U.S. Geological Survey, in cooperation with the Massachusetts Department of Environmental Protection, performed record extensions on groundwater levels at select wells using the Maintenance of Variance Extension type 1 (MOVE.1) method. The groundwater levels estimated from these record extensions were used to compute monthly percentiles to improve future determinations of a groundwater index.
Authors
Elizabeth A. Ahearn, Dee-Ann E. Crozier
Estimating flood magnitude and frequency on streams and rivers in Connecticut, based on data through water year 2015
The U.S. Geological Survey, in cooperation with the Connecticut Department of Transportation, updated flood-frequency estimates with 50-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent annual exceedance probabilities (2-, 5-, 10-, 25-, 50-, 100-, 200-, and 500-year recurrence intervals, respectively) for 141 streamgages in Connecticut and 11 streamgages in adjacent States using annual peak-flow data
Authors
Elizabeth A. Ahearn, Glenn A. Hodgkins
Methods for estimating regional coefficient of skewness for unregulated streams in New England, based on data through water year 2011
The magnitude of annual exceedance probability floods is greatly affected by the coefficient of skewness (skew) of the annual peak flows at a streamgage. Standard flood frequency methods recommend weighting the station skew with a regional skew to better represent regional and stable conditions. This study presents an updated analysis of a regional skew for New England developed using a robust Bay
Authors
Andrea G. Veilleux, Phillip J. Zarriello, Glenn A. Hodgkins, Elizabeth A. Ahearn, Scott A. Olson, Timothy A. Cohn
Flood inundation maps and water-surface profiles for tropical storm Irene and selected annual exceedance probability floods for Flint Brook and the Third Branch White River in Roxbury, Vermont
Flint Brook, a tributary to the Third Branch White River in Roxbury, Vermont, has a history of flooding the Vermont Fish and Wildlife Department’s Roxbury Fish Culture Station (the hatchery) and surrounding infrastructure. Flooding resulting from tropical storm Irene on August 28–29, 2011, caused widespread destruction in the region, including extensive and costly damages to the State-owned hatche
Authors
Elizabeth A. Ahearn, Pamela J. Lombard
Nutrient concentrations and loads in the northeastern United States - Status and trends, 1975-2003
The U.S. Geological Survey (USGS) National Water-Quality Assessment Program (NAWQA) began regional studies in 2003 to synthesize information on nutrient concentrations, trends, stream loads, and sources. In the northeastern United States, a study area that extends from Maine to central Virginia, nutrient data were evaluated for 130 USGS water-quality monitoring stations. Nutrient data were analyze
Authors
Elaine C. Todd Trench, Richard B. Moore, Elizabeth A. Ahearn, John R. Mullaney, R. Edward Hickman, Gregory E. Schwarz
Magnitude of flood flows for selected annual exceedance probabilities in Rhode Island through 2010
Heavy persistent rains from late February through March 2010 caused severe widespread flooding in Rhode Island that set or nearly set record flows and water levels at many long-term streamgages in the State. In response, the U.S. Geological Survey, in partnership with the Federal Emergency Management Agency, conducted a study to update estimates of flood magnitudes at streamgages and regional equa
Authors
Phillip J. Zarriello, Elizabeth A. Ahearn, Sara B. Levin
USGS library for S-PLUS for Windows -- Release 4.0
Release 4.0 of the U.S. Geological Survey S-PLUS library supercedes release 2.1. It comprises functions, dialogs, and datasets used in the U.S. Geological Survey for the analysis of water-resources data. This version does not contain ESTREND, which was in version 2.1. See Release 2.1 for information and access to that version.
This library requires Release 8.1 or later of S-PLUS for Windows. S-PL
Authors
David L. Lorenz, Elizabeth A. Ahearn, Janet M. Carter, Timothy A. Cohn, Wendy J. Danchuk, Jeffrey W. Frey, Dennis R. Helsel, Kathy Lee, David C. Leeth, Jeffrey D. Martin, Virginia L. McGuire, Kathleen M. Neitzert, Dale M. Robertson, James R. Slack, J. Jeffrey Starn, Aldo V. Vecchia, Donald H. Wilkison, Joyce E. Williamson
Connecticut Highlands technical report— Documentation of the regional rainfall-runoff model
This report provides the supporting data and describes the data sources, methodologies, and assumptions used in the assessment of existing and potential water resources of the Highlands of Connecticut and Pennsylvania (referred to herein as the “Highlands”). Included in this report are Highlands groundwater and surface-water use data and the methods of data compilation. Annual mean streamflow and
Authors
Elizabeth A. Ahearn, David M. Bjerklie
Regional Regression Equations to Estimate Flow-Duration Statistics at Ungaged Stream Sites in Connecticut
Multiple linear regression equations for determining flow-duration statistics were developed to estimate select flow exceedances ranging from 25- to 99-percent for six 'bioperiods'-Salmonid Spawning (November), Overwinter (December-February), Habitat Forming (March-April), Clupeid Spawning (May), Resident Spawning (June), and Rearing and Growth (July-October)-in Connecticut. Regression equations a
Authors
Elizabeth A. Ahearn
Flood of April 2007 and flood-frequency estimates at streamflow-gaging stations in western Connecticut
A spring nor’easter affected the East Coast of the United States from April 15 to 18, 2007. In Connecticut, rainfall varied from 3 inches to more than 7 inches. The combined effects of heavy rainfall over a short duration, high winds, and high tides led to widespread flooding, storm damage, power outages, evacuations, and disruptions to traffic and commerce. The storm caused at least 18 fatalities
Authors
Elizabeth A. Ahearn
Flow Durations, Low-Flow Frequencies, and Monthly Median Flows for Selected Streams in Connecticut through 2005
Flow durations, low-flow frequencies, and monthly median streamflows were computed for 91 continuous-record, streamflow-gaging stations in Connecticut with 10 or more years of record. Flow durations include the 99-, 98-, 97-, 95-, 90-, 85-, 80-, 75-, 70-, 60-, 50-, 40-, 30-, 25-, 20-, 10-, 5-, and 1-percent exceedances. Low-flow frequencies include the 7-day, 10-year (7Q10) low flow; 7-day, 2-year
Authors
Elizabeth A. Ahearn
Streamstats: U.S. Geological Survey web application for streamflow statistics for Connecticut
Introduction
An important mission of the U. S. Geological Survey (USGS) is to provide information on streamflow in the Nation's rivers. Streamflow statistics are used by water managers, engineers, scientists, and others to protect people and property during floods and droughts, and to manage land, water, and biological resources. Common uses for streamflow statistics include dam, bridge, and cu
Authors
Elizabeth A. Ahearn, Kernell G. Ries, Peter A. Steeves
Science and Products
Regional Regression Equations for Estimating Selected Low-flow Statistics at Ungaged Stream Sites in Massachusetts
The U.S. Geological Survey, in cooperation with the Massachusetts Department of Recreation and Conservation, Office of Water Resources, began a study in 2019 to update the regional regression equations for estimating selected low-flow statistics at ungaged sites in Massachusetts.
Developing Synthetic Historical Record at Groundwater Wells Using Record Extension Techniques
The Groundwater Index in the Massachusetts Drought Management Plan provides a general overview of groundwater levels relative to long-term groundwater levels in Massachusetts. The methods used to compute the Groundwater Index were revised for the 2019 version of the Drought Management Plan. The 2019 plan aligns the drought categories and specifies the drought status from select percentile ranges...
Development of Flood Insurance Maps in New England
FEMA has requested USGS expertise in hydraulics, hydrology, and mapping to generate flood insurance maps for New England.
Development of Regional Regression Equations in Connecticut
Knowledge of the magnitude and frequency of floods is needed for the effective and safe design of bridges, culverts, and other structures. This information is also important for flood-plain planning and management. Periodic examination of flood-frequency characteristics is essential to ensure the best estimates of flood magnitudes for a given annual exceedance probabilities (AEP).
Filter Total Items: 16
Estimating groundwater level records using MOVE.1 and computing monthly percentiles from estimated groundwater records in Massachusetts
The U.S. Geological Survey, in cooperation with the Massachusetts Department of Environmental Protection, performed record extensions on groundwater levels at select wells using the Maintenance of Variance Extension type 1 (MOVE.1) method. The groundwater levels estimated from these record extensions were used to compute monthly percentiles to improve future determinations of a groundwater index.
Authors
Elizabeth A. Ahearn, Dee-Ann E. Crozier
Estimating flood magnitude and frequency on streams and rivers in Connecticut, based on data through water year 2015
The U.S. Geological Survey, in cooperation with the Connecticut Department of Transportation, updated flood-frequency estimates with 50-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent annual exceedance probabilities (2-, 5-, 10-, 25-, 50-, 100-, 200-, and 500-year recurrence intervals, respectively) for 141 streamgages in Connecticut and 11 streamgages in adjacent States using annual peak-flow data
Authors
Elizabeth A. Ahearn, Glenn A. Hodgkins
Methods for estimating regional coefficient of skewness for unregulated streams in New England, based on data through water year 2011
The magnitude of annual exceedance probability floods is greatly affected by the coefficient of skewness (skew) of the annual peak flows at a streamgage. Standard flood frequency methods recommend weighting the station skew with a regional skew to better represent regional and stable conditions. This study presents an updated analysis of a regional skew for New England developed using a robust Bay
Authors
Andrea G. Veilleux, Phillip J. Zarriello, Glenn A. Hodgkins, Elizabeth A. Ahearn, Scott A. Olson, Timothy A. Cohn
Flood inundation maps and water-surface profiles for tropical storm Irene and selected annual exceedance probability floods for Flint Brook and the Third Branch White River in Roxbury, Vermont
Flint Brook, a tributary to the Third Branch White River in Roxbury, Vermont, has a history of flooding the Vermont Fish and Wildlife Department’s Roxbury Fish Culture Station (the hatchery) and surrounding infrastructure. Flooding resulting from tropical storm Irene on August 28–29, 2011, caused widespread destruction in the region, including extensive and costly damages to the State-owned hatche
Authors
Elizabeth A. Ahearn, Pamela J. Lombard
Nutrient concentrations and loads in the northeastern United States - Status and trends, 1975-2003
The U.S. Geological Survey (USGS) National Water-Quality Assessment Program (NAWQA) began regional studies in 2003 to synthesize information on nutrient concentrations, trends, stream loads, and sources. In the northeastern United States, a study area that extends from Maine to central Virginia, nutrient data were evaluated for 130 USGS water-quality monitoring stations. Nutrient data were analyze
Authors
Elaine C. Todd Trench, Richard B. Moore, Elizabeth A. Ahearn, John R. Mullaney, R. Edward Hickman, Gregory E. Schwarz
Magnitude of flood flows for selected annual exceedance probabilities in Rhode Island through 2010
Heavy persistent rains from late February through March 2010 caused severe widespread flooding in Rhode Island that set or nearly set record flows and water levels at many long-term streamgages in the State. In response, the U.S. Geological Survey, in partnership with the Federal Emergency Management Agency, conducted a study to update estimates of flood magnitudes at streamgages and regional equa
Authors
Phillip J. Zarriello, Elizabeth A. Ahearn, Sara B. Levin
USGS library for S-PLUS for Windows -- Release 4.0
Release 4.0 of the U.S. Geological Survey S-PLUS library supercedes release 2.1. It comprises functions, dialogs, and datasets used in the U.S. Geological Survey for the analysis of water-resources data. This version does not contain ESTREND, which was in version 2.1. See Release 2.1 for information and access to that version.
This library requires Release 8.1 or later of S-PLUS for Windows. S-PL
Authors
David L. Lorenz, Elizabeth A. Ahearn, Janet M. Carter, Timothy A. Cohn, Wendy J. Danchuk, Jeffrey W. Frey, Dennis R. Helsel, Kathy Lee, David C. Leeth, Jeffrey D. Martin, Virginia L. McGuire, Kathleen M. Neitzert, Dale M. Robertson, James R. Slack, J. Jeffrey Starn, Aldo V. Vecchia, Donald H. Wilkison, Joyce E. Williamson
Connecticut Highlands technical report— Documentation of the regional rainfall-runoff model
This report provides the supporting data and describes the data sources, methodologies, and assumptions used in the assessment of existing and potential water resources of the Highlands of Connecticut and Pennsylvania (referred to herein as the “Highlands”). Included in this report are Highlands groundwater and surface-water use data and the methods of data compilation. Annual mean streamflow and
Authors
Elizabeth A. Ahearn, David M. Bjerklie
Regional Regression Equations to Estimate Flow-Duration Statistics at Ungaged Stream Sites in Connecticut
Multiple linear regression equations for determining flow-duration statistics were developed to estimate select flow exceedances ranging from 25- to 99-percent for six 'bioperiods'-Salmonid Spawning (November), Overwinter (December-February), Habitat Forming (March-April), Clupeid Spawning (May), Resident Spawning (June), and Rearing and Growth (July-October)-in Connecticut. Regression equations a
Authors
Elizabeth A. Ahearn
Flood of April 2007 and flood-frequency estimates at streamflow-gaging stations in western Connecticut
A spring nor’easter affected the East Coast of the United States from April 15 to 18, 2007. In Connecticut, rainfall varied from 3 inches to more than 7 inches. The combined effects of heavy rainfall over a short duration, high winds, and high tides led to widespread flooding, storm damage, power outages, evacuations, and disruptions to traffic and commerce. The storm caused at least 18 fatalities
Authors
Elizabeth A. Ahearn
Flow Durations, Low-Flow Frequencies, and Monthly Median Flows for Selected Streams in Connecticut through 2005
Flow durations, low-flow frequencies, and monthly median streamflows were computed for 91 continuous-record, streamflow-gaging stations in Connecticut with 10 or more years of record. Flow durations include the 99-, 98-, 97-, 95-, 90-, 85-, 80-, 75-, 70-, 60-, 50-, 40-, 30-, 25-, 20-, 10-, 5-, and 1-percent exceedances. Low-flow frequencies include the 7-day, 10-year (7Q10) low flow; 7-day, 2-year
Authors
Elizabeth A. Ahearn
Streamstats: U.S. Geological Survey web application for streamflow statistics for Connecticut
Introduction
An important mission of the U. S. Geological Survey (USGS) is to provide information on streamflow in the Nation's rivers. Streamflow statistics are used by water managers, engineers, scientists, and others to protect people and property during floods and droughts, and to manage land, water, and biological resources. Common uses for streamflow statistics include dam, bridge, and cu
Authors
Elizabeth A. Ahearn, Kernell G. Ries, Peter A. Steeves