Riverbank erosion can alter channel geometry and progressively reduce bank support, yet reconnaissance studies often lack the hydraulic and geotechnical data required for formal stability modelling. This study evaluates whether simple field measurements can provide a defensible screening of geomorphic susceptibility along the Pattalasang River, South Sulawesi, Indonesia. Three cross-sections were examined: one comparatively stable baseline and two eroding sites. Cross-sectional areas were reconstructed by trapezoidal integration, erosion volumes were calculated from measured erosion dimensions, lateral concentration was expressed using an asymmetry index, and two grain-size distributions were compared descriptively. Quality control corrected a factor-of-four inconsistency in the original cross-sectional summaries, giving areas of 17.55, 14.70, and 13.25 m² for the baseline, Point I, and Point II. Erosion volume reached 74.96 m³ at Point I and 25.41 m³ at Point II. Left-bank erosion contributed 92.45% and 89.10% of site totals, with asymmetry indices of 0.849 and 0.782. Similar grain-size curves indicate that sediment gradation alone does not explain the 2.95-fold erosion contrast. The screening identifies Point I as the priority for repeat hydraulic and geotechnical assessment.
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