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Peter M McCarthy

Peter McCarthy is a Hydrologist for the Wyoming-Montana Water Science Center.

Peter's aims are to better understand streamflow statistics, streamflow responses to climate change, and to improve communication of USGS science to stakeholders and the public through improved web applications, tools, and software. He is the National StreamStats coordinator and the Water Mission Area Model Support Function Manager and works with hydrologists, web developer, and geospatial experts to ensure that tools, data, software, and web applications meet the needs of the USGS, stakeholders, and public. 

Professional Experience

  • 2017 to present, National StreamStats Coordinator, Wyoming-Montana Water Science Center, Helena, MT 

  • 2003-2017, Hydrologist, Wyoming-Montana Water Science Center, Helena, MT 

Education and Certifications

  • B.A. Mathematics-Carroll College 

  • B.S. Civil Engineering-Montana State University 

  • M.S. Civil Engineering-Colorado State University 

Science and Products

Filter Total Items: 15

Controlling skewness in MOVE3 peak-flow record extensions

Streamgage record extension methods such as the maintenance of variance Type 3 (MOVE3) method improve flood frequency estimates at a target streamgage by incorporating information from a nearby, hydrologically similar index streamgage. Bulletin 17C recommends using a variation of the MOVE3 method to estimate values at the target streamgage for only a subset of the available data at the index strea
Authors
Seth Arthur Siefken, Peter M. McCarthy
By
Water Resources Mission Area, Wyoming-Montana Water Science Center

Methods for peak-flow frequency analysis and reporting for streamgages in or near Montana based on data through water year 2015

This report documents the methods for peak-flow frequency (hereinafter “frequency”) analysis and reporting for streamgages in and near Montana following implementation of the Bulletin 17C guidelines. The methods are used to provide estimates of peak-flow quantiles for 50-, 42.9-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent annual exceedance probabilities for selected streamgages operated by the U.
Authors
Steven K. Sando, Peter M. McCarthy
By
Water Resources Mission Area, Wyoming-Montana Water Science Center

Methods for estimating peak-flow frequencies at ungaged sites in Montana based on data through water year 2011: Chapter F in Montana StreamStats

The U.S. Geological Survey (USGS), in cooperation with the Montana Department of Natural Resources and Conservation, completed a study to update methods for estimating peak-flow frequencies at ungaged sites in Montana based on peak-flow data at streamflow-gaging stations through water year 2011. The methods allow estimation of peak-flow frequencies (that is, peak-flow magnitudes, in cubic feet per
Authors
Roy Sando, Steven K. Sando, Peter McCarthy, DeAnn M. Dutton
By
Water Resources Mission Area, Wyoming-Montana Water Science Center, StreamStats

Peak-flow frequency analyses and results based on data through water year 2011 for selected streamflow-gaging stations in or near Montana: Chapter C in Montana StreamStats

Chapter C of this Scientific Investigations Report documents results from a study by the U.S. Geological Survey, in cooperation with the Montana Department of Transportation and the Montana Department of Natural Resources, to provide an update of statewide peak-flow frequency analyses and results for Montana. The purpose of this report chapter is to present peak-flow frequency analyses and results
Authors
Steven K. Sando, Peter McCarthy, DeAnn M. Dutton
By
Water Resources Mission Area, Wyoming-Montana Water Science Center, StreamStats

Methods for estimating streamflow characteristics at ungaged sites in western Montana based on data through water year 2009: Chapter G in Montana StreamStats

The U.S. Geological Survey, in cooperation with the Montana Department of Environmental Quality and the Montana Department of Natural Resources and Conservation, developed regional regression equations based on basin and streamflow characteristics for streamflow-gaging stations through water year 2009 that can be used to estimate streamflow characteristics for ungaged sites in western Montana. The
Authors
Peter McCarthy, Roy Sando, Steven K. Sando, DeAnn M. Dutton
By
Water Resources Mission Area, Wyoming-Montana Water Science Center, StreamStats

Montana StreamStats—A method for retrieving basin and streamflow characteristics in Montana: Chapter A in Montana StreamStats

The U.S. Geological Survey (USGS) provides streamflow characteristics and other related information needed by water-resource managers to protect people and property from floods, plan and manage water-resource activities, and protect water quality. Streamflow characteristics provided by the USGS, such as peak-flow and low-flow frequencies for streamflow-gaging stations, are frequently used by engin
Authors
Peter McCarthy, DeAnn M. Dutton, Steven K. Sando, Roy Sando
By
Water Resources Mission Area, Wyoming-Montana Water Science Center

Streamflow characteristics based on data through water year 2009 for selected streamflow-gaging stations in or near Montana: Chapter E in Montana StreamStats

Chapter E of this Scientific Investigations Report documents results from a study by the U.S. Geological Survey, in cooperation with the Montana Department of Environmental Quality and the Montana Department of Natural Resources and Conservation, to provide an update of statewide streamflow characteristics based on data through water year 2009 for streamflow-gaging stations in or near Montana. Str
Authors
Peter McCarthy
By
Water Resources Mission Area, Wyoming-Montana Water Science Center

Temporal trends and stationarity in annual peak flow and peak-flow timing for selected long-term streamflow-gaging stations in or near Montana through water year 2011: Chapter B in Montana StreamStats

A large-scale study by the U.S. Geological Survey, in cooperation with the Montana Department of Transportation and the Montana Department of Natural Resources and Conservation, was done to investigate general patterns in peak-flow temporal trends and stationarity through water year 2011 for 24 long-term streamflow-gaging stations (hereinafter referred to as gaging stations) in Montana. Hereinafte
Authors
Steven K. Sando, Peter McCarthy, Roy Sando, DeAnn M. Dutton
By
Water Resources Mission Area, Wyoming-Montana Water Science Center, StreamStats

Adjusted peak-flow frequency estimates for selected streamflow-gaging stations in or near Montana based on data through water year 2011: Chapter D in Montana StreamStats

The climatic conditions of the specific time period during which peak-flow data were collected at a given streamflow-gaging station (hereinafter referred to as gaging station) can substantially affect how well the peak-flow frequency (hereinafter referred to as frequency) results represent long-term hydrologic conditions. Differences in the timing of the periods of record can result in substantial
Authors
Steven K. Sando, Roy Sando, Peter McCarthy, DeAnn M. Dutton
By
Water Resources Mission Area, Wyoming-Montana Water Science Center

Lateral and vertical channel movement and potential for bed-material movement on the Madison River downstream from Earthquake Lake, Montana

The 1959 Hebgen Lake earthquake caused a massive landslide (Madison Slide) that dammed the Madison River and formed Earthquake Lake. The U.S. Army Corps of Engineers excavated a spillway through the Madison Slide to permit outflow from Earthquake Lake. In June 1970, high streamflows on the Madison River severely eroded the spillway channel and damaged the roadway embankment along U.S. Highway 287
Authors
Katherine J. Chase, Peter McCarthy
By
Water Resources Mission Area, Wyoming-Montana Water Science Center

A digital model for planning water management at Benton Lake National Wildlife Refuge, west-central Montana

Benton Lake National Wildlife Refuge is an important area for waterfowl production and migratory stopover in west-central Montana. Eight wetland units covering about 5,600 acres are the essential features of the refuge. Water availability for the wetland units can be uncertain owing to the large natural variations in precipitation and runoff and the high cost of pumping supplemental water. The U.S
Authors
David A. Nimick, Peter McCarthy, Vanessa Fields
By
Water Resources Mission Area, Wyoming-Montana Water Science Center

Estimation of Streamflow Characteristics for Charles M. Russell National Wildlife Refuge, Northeastern Montana

Charles M. Russell National Wildlife Refuge (CMR) encompasses about 1.1 million acres (including Fort Peck Reservoir on the Missouri River) in northeastern Montana. To ensure that sufficient streamflow remains in the tributary streams to maintain the riparian corridors, the U.S. Fish and Wildlife Service is negotiating water-rights issues with the Reserved Water Rights Compact Commission of Montan
Authors
Steven K. Sando, Timothy J. Morgan, DeAnn M. Dutton, Peter McCarthy
By
Water Resources Mission Area, Wyoming-Montana Water Science Center
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Drainage basin delineation using the StreamStats web application for South Carolina.

South Carolina Streams Stats: Phase 2

This project will enhance the USGS StreamStats web application in South Carolina (Phase II) by incorporating additional tools and functionality into the current (2019) application. In addition, a separate application, Floodplain Width and Indirect Determination of Extent (Flood WIDE), will be developed to incorporate functions that will provide additional tools for the SCDOT and other engineers...
By
South Atlantic Water Science Center (SAWSC)
link

South Carolina Streams Stats: Phase 2

This project will enhance the USGS StreamStats web application in South Carolina (Phase II) by incorporating additional tools and functionality into the current (2019) application. In addition, a separate application, Floodplain Width and Indirect Determination of Extent (Flood WIDE), will be developed to incorporate functions that will provide additional tools for the SCDOT and other engineers...
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link
USGS science for a changing world logo

Building a framework to compute continuous grids of basin characteristics for the conterminous United States

The proposed work will create a seamless pilot dataset of continuous basin characteristics (for example upstream average precipitation, elevation, or dominant land cover type) for the conterminous United States. Basin characteristic data are necessary for training or parameterizing statistical, machine learning, and physical models, and for making predictions across the landscape, particularly in
By
Community for Data Integration (CDI)
link

Building a framework to compute continuous grids of basin characteristics for the conterminous United States

The proposed work will create a seamless pilot dataset of continuous basin characteristics (for example upstream average precipitation, elevation, or dominant land cover type) for the conterminous United States. Basin characteristic data are necessary for training or parameterizing statistical, machine learning, and physical models, and for making predictions across the landscape, particularly in
Learn More
link
USGS science for a changing world logo

Developing a "fire-aware" stream gage network by integrating USGS enterprise databases

Wildfires affect streams and rivers when they burn vegetation and scorch the ground. This makes floods more likely to happen and reduces water quality. Public managers, first responders, fire scientists, and hydrologists need timely information before and after a fire to plan for floods and water treatment. This project will create a method to combine national fire databases with the StreamStats w
By
Community for Data Integration (CDI)
link

Developing a "fire-aware" stream gage network by integrating USGS enterprise databases

Wildfires affect streams and rivers when they burn vegetation and scorch the ground. This makes floods more likely to happen and reduces water quality. Public managers, first responders, fire scientists, and hydrologists need timely information before and after a fire to plan for floods and water treatment. This project will create a method to combine national fire databases with the StreamStats w
Learn More
link
PROSPER in StreamStats screenshot

StreamStats: Streamflow Statistics and Spatial Analysis Tools for Water-Resources Applications

StreamStats provides access to spatial analytical tools that are useful for water-resources planning and management, and for engineering and design purposes. The map-based user interface can be used to delineate drainage areas, get basin characteristics and estimates of flow statistics, and more. Available information varies from state to state.
By
Water Resources Mission Area
link

StreamStats: Streamflow Statistics and Spatial Analysis Tools for Water-Resources Applications

StreamStats provides access to spatial analytical tools that are useful for water-resources planning and management, and for engineering and design purposes. The map-based user interface can be used to delineate drainage areas, get basin characteristics and estimates of flow statistics, and more. Available information varies from state to state.
Learn More
link
Screenshot of National Streamflow Statistics Program (NSS) data entry

National Streamflow Statistics Program: Known Issues

The National Streamflow Statistics (NSS) Program compiles regression equations for estimating streamflow statistics for every state, Puerto Rico, and a number of metropolitan areas in the U.S. This page documents known issues with the NSS software program.
By
Water Resources Mission Area
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National Streamflow Statistics Program: Known Issues

The National Streamflow Statistics (NSS) Program compiles regression equations for estimating streamflow statistics for every state, Puerto Rico, and a number of metropolitan areas in the U.S. This page documents known issues with the NSS software program.
Learn More
link
USGS Rural Peak-Flow Regression Equations

National Streamflow Statistics Application: Regional Regression Equation Publications by State or Territory

The National Streamflow Statistics (NSS) Application compiles regression equations for estimating streamflow statistics for every state, Puerto Rico, and a number of metropolitan areas in the U.S.
By
Water Resources Mission Area
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National Streamflow Statistics Application: Regional Regression Equation Publications by State or Territory

The National Streamflow Statistics (NSS) Application compiles regression equations for estimating streamflow statistics for every state, Puerto Rico, and a number of metropolitan areas in the U.S.
Learn More
link
Screenshot of National Streamflow Statistics Program (NSS) data entry

National Streamflow Statistics Program: Version History

The National Streamflow Statistics (NSS) Program compiles regression equations for estimating streamflow statistics for every state, Puerto Rico, and a number of metropolitan areas in the U.S. This page documents updates made to the NSS software program and database.
By
Water Resources Mission Area
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National Streamflow Statistics Program: Version History

The National Streamflow Statistics (NSS) Program compiles regression equations for estimating streamflow statistics for every state, Puerto Rico, and a number of metropolitan areas in the U.S. This page documents updates made to the NSS software program and database.
Learn More
link
MT StreamStats Screenshot of Interactive Map

StreamStats in Montana and Wyoming

StreamStats is a Web application that provides access to an assortment of Geographic Information Systems (GIS) analytical tools that are useful for water-resources planning and management, and for engineering and design purposes.
By
Wyoming-Montana Water Science Center
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StreamStats in Montana and Wyoming

StreamStats is a Web application that provides access to an assortment of Geographic Information Systems (GIS) analytical tools that are useful for water-resources planning and management, and for engineering and design purposes.
Learn More
Filter Total Items: 13

Peak-flow frequency analyses for selected streamgages in Dawson and Richland Counties, and the Powder River Basin, Montana, based on data through water year 2022

The USGS Wyoming-Montana Water Science Center (WY–MT WSC) completed a report (Sando and McCarthy, 2018) documenting methods for peak-flow frequency analysis following implementation of the Bulletin 17C guidelines. The methods are used to provide estimates of peak-flow quantiles for 66.7-, 50-, 42.9-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent annual exceedance probabilities (AEPs) for selected US
By
Wyoming-Montana Water Science Center

Peak-flow frequency analyses for selected streamgages in and near the Milk River Basin, Montana, based on data through water year 2018, part 2

The USGS Wyoming-Montana Water Science Center (WY–MT WSC) completed a report (Sando and McCarthy, 2018) documenting methods for peak-flow frequency analysis following implementation of the Bulletin 17C guidelines. The methods are used to provide estimates of peak-flow quantiles for 66.7-, 50-, 42.9-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent annual exceedance probabilities (AEPs) for selected st
By
Wyoming-Montana Water Science Center

Peak-flow frequency analyses for selected streamgages on the Bighorn, Tongue, and Lower Yellowstone Rivers and tributaries and Home Creek, Montana, based on data through water year 2021

The USGS Wyoming-Montana Water Science Center (WY–MT WSC) completed a report (Sando and McCarthy, 2018) documenting methods for peak-flow frequency analysis following implementation of the Bulletin 17C guidelines. The methods are used to provide estimates of peak-flow quantiles for 66.7-, 50-, 42.9-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent annual exceedance probabilities (AEPs) for selected st
By
Wyoming-Montana Water Science Center

Peak-flow frequency analyses for selected streamgages in and near Teton County, Montana, based on data through water year 2019

The USGS Wyoming-Montana Water Science Center (WY-MT WSC) completed a report (Sando and McCarthy, 2018) documenting methods for peak-flow frequency analysis following implementation of the Bulletin 17C guidelines. The methods are used to provide estimates of peak-flow quantiles for 66.7-, 50-, 42.9-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent annual exceedance probabilities (AEPs) for selected st
By
Wyoming-Montana Water Science Center

Peak-flow frequency analyses for selected streamgages in and near the Milk River Basin, Montana, based on data through water year 2018, Part 1

The USGS Wyoming-Montana Water Science Center (WY?MT WSC) completed a report (Sando and McCarthy, 2018) documenting methods for peak-flow frequency analysis following implementation of the Bulletin 17C guidelines. The methods are used to provide estimates of peak-flow quantiles for 50-, 42.9-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent annual exceedance probabilities (AEPs) for selected streamgag
By
Wyoming-Montana Water Science Center

Flow-Conditioned Parameter Grids for the Contiguous United States: A Pilot, Seamless Basin Characteristic Dataset

Abstract To aid in parameterization of mechanistic, statistical, and machine learning models of hydrologic systems in the contiguous United States (CONUS), flow-conditioned parameter grids (FCPGs) have been generated describing upstream basin mean elevation, slope, land cover class, latitude, and 30-year climatologies of mean total annual precipitation, minimum daily air temperature, and maximum d
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Community for Data Integration (CDI), Wyoming-Montana Water Science Center

Dam impact/disturbance metrics for the conterminous United States, 1800 to 2018

This metadata record describes two metrics that quantitatively measure the impact of reservoir storage on every flowline in the NHDPlus version 2 data suite (NHDPlusV2) for the conterminous United States. These metrics are computed for every 10 years from 1800 - 2015. The first metric (DamIndex_EROM.zip) estimates reservoir storage intensity in units of days based on reservoir storage in a contrib
By
Maryland-Delaware-D.C. Water Science Center

Peak-flow frequency analyses for selected streamgages in Carbon County, Montana, based on data through water year 2018

The USGS Wyoming-Montana Water Science Center (WY-MT WSC) documented (Sando and McCarthy, 2018) methods for peak-flow frequency analysis following implementation of the Bulletin 17C guidelines. The methods are used to provide estimates of peak-flow quantiles for 50-, 42.9-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent annual exceedance probabilities (AEPs) for selected streamgages operated by the W
By
Wyoming-Montana Water Science Center

Peak-flow frequency analyses for 14 selected streamgages in the Beaverhead River and Clark Fork Basins Montana, based on data through water year 2016

The USGS Wyoming-Montana Water Science Center (WY-MT WSC) recently completed a report (Sando and McCarthy, 2018) documenting methods for peak-flow frequency analysis following implementation of the Bulletin 17C guidelines. The methods are used to provide estimates of peak-flow quantiles for 50-, 42.9-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent annual exceedance probabilities (AEPs) for selected
By
Wyoming-Montana Water Science Center

Peak-flow frequency analyses for 99 selected streamgages in or near Montana, based on data through water year 2015 (ver. 1.1, August 2020)

The USGS Wyoming-Montana Water Science Center (WYMT WSC) recently completed a report documenting methods for peak-flow frequency analysis following implementation of the Bulletin 17C guidelines. The methods are used to provide estimates of peak-flow quantiles for 50-, 42.9-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent annual exceedance probabilities (AEPs) for selected streamgages operated by the
By
Wyoming-Montana Water Science Center

Peak-Flow Frequency Analyses for Selected Streamgages in Missoula and Granite Counties, Montana, Based on Data through Water Year 2018

The USGS Wyoming-Montana Water Science Center (WY?MT WSC) completed a report (Sando and McCarthy, 2018) documenting methods for peak-flow frequency analysis following implementation of the Bulletin 17C guidelines. The methods are used to provide estimates of peak-flow quantiles for 50-, 42.9-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent annual exceedance probabilities (AEPs) for selected streamgag
By
Wyoming-Montana Water Science Center

Channel width measurements for selected streamgage sites in Montana

The WY-MT WSC conducted a study to develop regression equations for estimating peak-flow frequencies in Montana, using channel-width characteristics. Channel widths were measured in the field and from aerial photographs. This data release includes three child items: a table of field measurements, a table of measurements from aerial photographs, and a summary table of the data (field measurements a
By
Wyoming-Montana Water Science Center

Peak Flow Frequency R EXtensions

R tools to assist with peak-flow frequency analysis using the USGS PeakFQ software.
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Wyoming-Montana Water Science Center

Flow-Conditioned Parameter Grid Tools

The Flow-Conditioned Parameter Grid (FCPG) Tools are a Python 3 library to make FCPGs for either two-digit Hydrologic Unit Code (HUC2) regions, four-digit Hydrologic Unit Code (HUC4) regions, or other geospatial tiling schemes. These tools can be used in a Linux-based high performance computing (HPC) environment or locally on your system.

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Community for Data Integration (CDI), Wyoming-Montana Water Science Center

StreamStats Data Preparation Tools, version 4

A Python package to pre-process and hydro-enforce digital elevation models using hydrography features for use in the U.S. Geological Survey (USGS) StreamStats project.

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Wyoming-Montana Water Science Center

National Streamflow Statistics (NSS) Application - Formerly NSS Program

The USGS develops regression equations for estimating streamflow statistics for every state, Puerto Rico, and a number of metropolitan areas in the U.S. These equations have been compiled into the National Streamflow Statistics (NSS) Application for design, planning, management, and regulatory purposes. These estimates are often needed at ungaged sites where no observed flow data are available.

By
Water Resources Mission Area, StreamStats
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StreamStats Provides New Information for Montana

Helpful new information for anyone designing structures over or near water, managing water distribution, or interested in the flow of local streams.

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