Project C05.2018: Leveraging High-Resolution LiDAR and Stream Geomorphic Assessment Datasetsto Expand Regional Hydraulic Geometry Curves for Vermont: A Blueprint for NewEngland States

Leveraging High-Resolution LiDAR and Stream Geomorphic Assessment Datasets to Expand Regional Hydraulic Geometry Curves for Vermont: A Blueprint for New England States

Project C5.2018

Project Summary

Regional hydraulic geometry curves (RHGCs) for Vermont have been updated through development of additional observations and use of newly-available high-resolution lidar and stream geomorphic assessment data to improve the prediction ability and reduce estimation uncertainty of bankfull channel dimensions for ungauged sites. Through literature review and data compilation, we have identified 10 additional observation sites with sufficiently robust geomorphic assessment data and co-located streamflow monitoring records. Application of RHGCs has been expanded to cover drainage areas up to 396 (from 194) square miles. Stratification of the curves by channel slope at a threshold of 0.1% improved prediction of bankfull width as a function of drainage area. Targeted geomorphic assessment field work and establishment of temporary streamflow monitoring stations under future funding would enable further expansion of RHGCs to better address very-low-gradient channels and add coverage for steep-gradient streams.

Principal Investigator

Dr. Kristen L. Underwood


Dr. Arne Bomblies
Dr. Donna Rizzo


University of Vermont

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Office of the Assistant Secretary for Research and Technology, University Transportation Centers Program, Department of Transportation, University of Vermont .

Implementation of Research Outcomes:

Updated regional curves are publicly-available for use by transportation
departments of the New England states, as well as engineers and scientists working
at private firms, non-governmental organizations and state and federal agencies.

Impacts and Benefits of Implementation:

Updated curves will support sizing of stream crossing structures as well as flood
recovery efforts along road embankments to restore river cross sections of sufficient
width to convey bankfull flows. Geomorphically-compatible structures will have
greater resilience to extreme flood events and will support aquatic and terrestrial
organism passage objectives.

Printable Project Information Sheet

Printable Final Report

September 2019 Semi-Annual Progress Report

January 2020 Quarterly Progress Report

March 2020 Quarterly Progress Report

June 2020 Quarterly Progress Report

September 2020 Quarterly Progress Report

December 2020 Quarterly Progress Report

March 2021 Quarterly Progress Report