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We have developed a methodology to assess the risk associated with sediment gravity flows, using numerical simulations of coastal circulation forced by storms to determine the conditions necessary to trigger turbidity currents and to model its evolution downslope. The workflow involves: (1) Hindcast analysis of wind, waves, precipitation, and river discharge. (2) Hydrological modelling of the river basin to determine the sediment delivery. (3) Determination of the return periods of storm events and their quantitative characteristics in terms of wind speed/direction, wave height/period/direction and river discharge. (4) Development of a coastal circulation model, to quantify wave-, current- and tidal-induced currents and the ensuing sediment transport. (5) Determining under which storm conditions turbidity currents are triggered and whether they accelerate into the deep ocean, potentially impacting an infrastructure location. The results of the simulations are analysed statistically, with the aim of estimating the return periods of turbidity currents that can impact an existing or planned infrastructure. Detailed 3D turbidity current simulations are used to estimate the forces impacting the infrastructure, providing information that can assist the detailed design of installation, maintenance and mitigating measures.