Flood mitigation via dispersed hydraulic structures at watershed scale
Laminage des crues par petits ouvrages hydrauliques répartis sur le bassin versant
Résumé
Uncoordinated flood defense strategies too often while protecting one area, aggravate the situation elsewhere. Dry dams do attenuate the flood peak by holding back water only during floods. Our study looks at the hydrological impact of several dry dams dispersed along the drainage network. Our tests were carried out on a 150 km² semi-virtual test-case created from real data. Spatially distibuted precipitations from a stochastic model (TBM, Cemagref, Lyon) are used as input to a distributed hydrological model (Marine, IMF Toulouse) which computes the runoff from the hillslopes and feeds it in turn to a hydraulic model (Mage, Cemagref, Lyon). The impacts of dry dams orange of high flows. The efficiency of dry dams regarding to their location in space is addressed.