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A warming climate and chronically-diminished snowpacks are straining water resources in the western United States. Properly functioning riparian systems slow runoff, store water, regulate extreme flows, and in the case of losing streams they recharge aquifers; however, riparian areas across the west are degraded with a majority of BLM-managed riparian systems not in proper functioning condition. Widespread catastrophic erosion of water-storing peat and organic soils has destroyed many kilometers of linear water-storage capacity leaving gravel-bottom ditches that speed watershed outflow causing flooding in areas downstream. Headcuts are the leading edge of catastrophic channel erosion. We used aerial imagery (1.4 to 2.6-cm pixel) to locate 163 headcuts in riparian areas in the Sweetwater subbasin of central Wyoming. Structure-from-Motion models, built from ground-acquired imagery, were used to model soil loss equivalent to 425-720 cubic meters from 19 headcuts. Normalized by channel length, this represents a loss of 1.1-1.8 cubic meters per meter of channel. These Structure-from-Motion models provide baseline position/elevation for trend monitoring. Monitoring from ground or aerial imagery provides an objective, permanent indicator of sustainable riparian land management and identifies priority disturbance-mitigation areas. Image-based headcut monitoring must use data on the order of 2.6-cm GSD, or greater resolution, to effectively capture the information needed for accurate assessments of riparian conditions.