Automatic incorporation of riverbank failures in two-dimensional flood modeling

Riverbanks undergo changes caused not only by river hydraulics, mainly sediment erosion and deposition processes, but also the possible landslides that eventually change channel bank profiles. Those failures are an important form of alluvial adjustments usually difficult to include during morphodynamic modeling. This paper proposes a novel approach combining 2D depth-averaged hydrodynamic, transport mobile-bed model, SRH-2D, limit equilibrium slope-stability BISHOP, failure redistribution submodel, REDISSED, into fully automatic continuous dynamic simulation predict vertical bed lateral for reach undergoing exceptional flooding. The in-stream fluvial predicted with SRH-2D model will be automatically used update riverbank geometry profile assess their geotechnical stability rotational slip developed based on Bishop’s simplified method. A cone-shaped sliding area is defined in case driving forces exceed stabilizing forces. All mesh nodes located within mass wasting zone updated, allowing new face form. failed materials redistributed transect according observed at study site. Outaouais River Notre-Dame-Du Nord, Quebec, test coupling procedure. Up 100 m retreat was predicted, more than 20 cross-sections were reshaped. Typical results showing effectiveness framework presented discussed.