Application of unmanned aircraft system (UAS) for monitoring bank erosion along river corridors

Abstract

Excessive streambank erosion is a significant source of fine sediments and associated nutrients in many river systems as well as poses risk to infrastructure. Geomorphic change detection using high-resolution topographic data is a useful method for monitoring the extent of bank erosion along river corridors. Recent advances in an unmanned aircraft system (UAS) and structure from motion (SfM) photogrammetry techniques allow acquisition of high-resolution topographic data, which are the methods used in this study. To evaluate the effectiveness of UAS-based photogrammetry for monitoring bank erosion, a fixed-wing UAS was deployed to survey 20 km of river corridors in central Vermont, in the northeastern United States multiple times over a two-year period. Digital elevation models (DEMs) and DEMs of difference allowed quantification of volumetric changes along selected portions of the survey area where notable erosion occurred. Results showed that UAS was capable of collecting high-quality topographic data at fine resolutions even along vegetated river corridors provided that the surveys were conducted in early spring, after snowmelt but prior to summer vegetation growth. Longer term estimates of streambank movements using the UAS showed good comparison to previously collected airborne lidar surveys and allowed reliable quantification of significant geomorphic changes along rivers.

Keywords:

• Unmanned aircraft system (UAS)
• photogrammetry
• streambank erosion
• rivers

Acknowledgements

The views, opinions, findings, and conclusions reflected in this paper are solely those of the authors and do not represent the official policy or position of any funding sources or endorse any third‐party products or services that may be included in this presentation or associated materials. The authors acknowledge the additional contributions of the University of Vermont (UVM) Spatial Analysis Lab UAS team and Kristen Underwood.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This research was supported by the Vermont Water Resources and Lakes Studies Center. Additional support provided by Vermont EPSCoR with funds from the National Science Foundation (NSF) Grant EPS‐1101317 and OIA‐1556770, NSF Grant CMMI‐1229045, NSF Graduate Research Fellowship under Grant DGE‐0925179NSF, the Robert & Patricia Switzer Foundation, the Gund Institute for Environment, and Grant OASRTRS‐14‐H‐ UVM from the US Department of Transportation are also gratefully acknowledged.