Durance River in South East of France is highly influenced by Serre-Ponçon and Sainte Croix dams. With those dams, regular floods no longer clear vegetation in Durance River bed. EDF manages those dams and has to clear vegetation to replace flood action to avoid worsening extreme floods. Authorities in charge of flood safety management ask EDF for an important clearing of vegetation, and authorities in charge of Environment ask EDF to preserve vegetation as much as possible. To reconcile those

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... wo opposite objectives, a prefectural decree was published asking EDF to preserve vegetation if it doesn't worsen water level in flood plain (increase between with and without vegetation of less than 5 cm in highly sensitive areas – urban areas – and less than 10 cm in moderately sensitive areas – agricultural areas). To answer that prefectural decree, EDF chooses to model Durance River from Serre-Ponçon dam to its confluence with Rhone River (204 km). 14 TELEMAC-2D models are or will be built to optimise the clearing of vegetation. Durance bed changes often, therefore those models and their calibration are updated regularly. This article focuses on two models: "Bonpas Le Rhône", just upstream of the confluence with the Rhône River, and "Brillanne", a part of Durance between the confluence with the Bléone River and the confluence with the Verdon River. It details methodology for construction, updates, calibration and way of optimisation.