The third stage of the Aire River restoration in Geneva is a multi-objective project including a 600 m long dam for flood control, a 8000 m3 sedimentation reservoir and a 1100 m long rehabilitated meandering reach. Beyond river revitalisation issues, the main goal of the project is to optimise appurtenant works dedicated to flood risk management routing, sediment transport, driftwood and fish migration, an opitmisation study was carried out on a physical hydraulic model in the Laboratory for Applied Hydraulics of hepia-Geneva to the original hydraulic design of the project, more particulatrly flow diversion, energy dissipation, driftwood retention, sediment management and fish migration. Significant benefits obtained from the physical modelling are highlighted and illustrated by pictures of the real project under construction.