Remote detection of streambank erosion and channel incision using high-resolution repeat lidar-derived metrics in Raleigh, North Carolina

Laura N. Gurley; Kristina G. Hopkins; Charles C. Stillwell; Deanna Hardesty

doi:10.1002/esp.70415

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Remote detection of streambank erosion and channel incision using high-resolution repeat lidar-derived metrics in Raleigh, North Carolina

Laura N. Gurley·Kristina G. Hopkins·Charles C. Stillwell·Deanna Hardesty

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Abstract

This study evaluated the use of lidar data to detect streambank erosion and channel incision throughout Raleigh, North Carolina. The study included five components. (1) Generation of lidar-derived rasters, including a digital elevation model of difference that represented channel erosion and positive openness rasters that represented channel incision. (2) Completion of site-based field assessments throughout the study area. (3) Spatial analysis of raster datasets at three spatial scales: erosion patches, channel segments, and subbasins. (4) Comparison of field assessment results with lidar-derived metrics. (5) Pairing of landscape attributes with lidar-derived metrics to evaluate potential causative factors associated with variations in channel incision. Field assessment results indicated 74% of surveyed sites had Bank Erosion Hazard Index ratings ranging from ‘high’ to ‘extreme’ and 77% had ‘high’ or ‘severe’ degrees of channel incision. Select field measures showed agreement with lidar-derived metrics. Lidar-derived erosion patches, ranging in size from 20 to 948 m 2 , were detected in 24.3% of channel segments, and patch density increased with Strahler stream order. Channel segments, ranging from 50 to 150 m, had inconsistent spatial patterns of erosion and incision. Erosion in channel segments increased with Strahler stream order and 36% of channel segments became more incised during the study period. Lidar-derived metrics across subbasins revealed variability of erosion and incision throughout the study area. The assessment of landscape drivers could not explain variability at the channel-segment scale, but subbasins with fewer forests tended to have greater erosion and incision. However, unexplained variability remained, demonstrating the complexity of stream stability in urban watersheds. As lidar datasets become more widespread, pairing remote data with field assessments may be a viable approach to characterize and understand stream geomorphology in urban settings.

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Earth Surface Processes and Landforms Article

Source-reported bounding extent: 35.667° to 36.1° latitude; -78.9° to -78.4167° longitude. This indicates report coverage, not an exact sampling location. View area on OpenStreetMap.

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BibTeX RIS

Laura N. Gurley, Kristina G. Hopkins, Charles C. Stillwell, Deanna Hardesty. 2026-09-23. Remote detection of streambank erosion and channel incision using high-resolution repeat lidar-derived metrics in Raleigh, North Carolina. https://doi.org/10.1002/esp.70415

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