A simplified approach for probabilistically-based design of flood attenuation reservoirs

The flood peak attenuation reservoirs are very effective structural measures, able to reduce the flood damage by partially storing the flood volumes. In order to identify and select the locations which are suitable for the allocation of such reservoirs, preliminary design formulas are used: a number of these formulas can be found in literature, aiming to correlate, for given design hydrographs, the flood peak attenuation to the ratio between the reservoir and flood volumes. In this paper, a probabilistically-based, though simplified approach is proposed, which takes into account the geomorpho-climatic characterisation of the drainage basin, and which avoids the use of a design hydrograph.