Heavy rainfall and a changing climate have a direct correlation with the frequency of large geohazard events. Rainfall is a crucial factor in developing debris flow risk mitigation strategies in a Tasmanian context. Current methods to assess the magnitude of catastrophic debris flows and landslides often account for a variety of possible precipitation events, incorporating inherent variability, uncertainty and spatial variability for rainfall and run-off. Although uncertainty, heterogeneity and spatial dependencies are commonplace in assessing rainfall for debris flow risk, large-scale probabilistic methods have yet to incorporate the variability of geotechnical and hydrological factors.

Numerical simulations have shown that the destructive potential debris flows are particularly sensitive to initial conditions, including debris flow orientation and position, channel geometry, surface roughness and sedimentary concentrations. This research aims to quantify the effects of debris flow uncertainties on the performance protective structures such as check dams, rigid barriers and flexible nets. The project will develop probabilistic methods for Monte Carlo simulation of debris flow run-out behaviour, as well as debris flow barrier performance, incorporating probabilistic assessment tools as part of random field theory, coupled with large deformation numerical simulation. The creation of innovative probabilistic models will drive sustainable engineering solutions for risk mitigation, accommodating for debris flow uncertainty, heterogeneity and spatial variability.