The flood-frequency characteristics for streamgages and regression equations for estimating flood magnitudes have been published.
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. The flood-frequency characteristics for streamgages and regression equations for estimating flood magnitudes at ungaged sites were last developed in 1999.
New analyses benefit from 20 additional years of data including many sites with small (< 30 mi2 watersheds) and state of the art methods.
Objectives:
- Calculate magnitude of peak flows for 50-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent Annual Exceedance Probabilities (AEP) at streamgages in Maine using up-to-date methods and data collected through 2017;
- Evaluate peaks flow data in Maine for potential trends over period of record;
- Determine basin characteristics that are most important for predicting peak flows in regional-regression equations;
- Produce new regional regression equations for estimating the 50-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent AEP flows at ungaged sites in Maine;
- Document the methods and findings in a USGS publication,
- Incorporate new estimates and equations into the U.S. Geological Survey (USGS) StreamStats Program http://water.usgs.gov/osw/streamstats/.
- Concurrently update Streamstats with the newest Maine Lidar, up to date drainage basin delineations at all gages, land up-to-date digital coverages of basin characteristics including a watershed basin delineation (WBD) layer based on new lidar.
Results of peak-flow frequency analysis and regionalization for selected streamgages in or near Maine, based on data through water year 2019
Estimating flood magnitude and frequency on gaged and ungaged streams in Maine
Estimating the magnitude of peak flows for streams in Maine for selected recurrence intervals
- Overview
The flood-frequency characteristics for streamgages and regression equations for estimating flood magnitudes have been published.
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. The flood-frequency characteristics for streamgages and regression equations for estimating flood magnitudes at ungaged sites were last developed in 1999.
New analyses benefit from 20 additional years of data including many sites with small (< 30 mi2 watersheds) and state of the art methods.
Objectives:
- Calculate magnitude of peak flows for 50-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent Annual Exceedance Probabilities (AEP) at streamgages in Maine using up-to-date methods and data collected through 2017;
- Evaluate peaks flow data in Maine for potential trends over period of record;
- Determine basin characteristics that are most important for predicting peak flows in regional-regression equations;
- Produce new regional regression equations for estimating the 50-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent AEP flows at ungaged sites in Maine;
- Document the methods and findings in a USGS publication,
- Incorporate new estimates and equations into the U.S. Geological Survey (USGS) StreamStats Program http://water.usgs.gov/osw/streamstats/.
- Concurrently update Streamstats with the newest Maine Lidar, up to date drainage basin delineations at all gages, land up-to-date digital coverages of basin characteristics including a watershed basin delineation (WBD) layer based on new lidar.
- Data
Results of peak-flow frequency analysis and regionalization for selected streamgages in or near Maine, based on data through water year 2019
The U.S. Geological Survey (USGS) recently completed a report documenting methods for peak-flow frequency analysis following implementation of the Bulletin 17C guidelines (https://doi.org/10.3133/tm4B5). The methods provide estimates of peak-flow quantiles for 50-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent annual exceedance probabilities (AEPs) for selected streamgages operated by the USGS and E - Publications
Estimating flood magnitude and frequency on gaged and ungaged streams in Maine
Accurate estimates of flood frequency and magnitude on rivers and streams in Maine are a key component of effective flood risk management, flood mitigation, and flood recovery programs for the State. Flood-frequency estimates are published here for 148 streamgages in and adjacent to Maine. Equations are provided for users to compute flood-frequency estimates at any location on a stream that does nEstimating the magnitude of peak flows for streams in Maine for selected recurrence intervals
This report gives estimates of, and presents techniques for estimating, the magnitude of peak flows for streams in Maine for recurrence intervals of 2, 5, 10, 25, 50, 100, and 500 years. A flowchart in this report guides the user to the appropriate estimates and (or) estimating techniques for a site on a specific stream. Section 1, 'Estimates of peak flows and maximum recorded flows at USGS st