A large-scale stress-geology interaction simulation was performed for Snowy Hydro Limited, aimed to simulate the existing stress state at the planned Snowy 2.0 Hydropower tunnel alignment and thereby increase understanding of current stress state and increase the confidence of the stress measurement data. The simulation was originally run using three-dimensional distinct element code 3DEC, but later rerun based on an updated geological model using FLAC3D due to a faster solution. The simulation model consisted of the fault zones and lithological units as modelled by the project geologists and incorporated either the interpreted or measured mechanical properties of the different rock types and faults. The simulation was run by applying velocity boundary conditions at the boundaries of the simulation model, mimicking tectonic movements. The orientation of the applied velocities were based on available stress measurement data for the Snowy 2.0 project, GPS-measurement data, knowledge of the latest paleostress field and World Stress Map data. The simulation was calibrated against high-quality stress measurement data from the project site and using the results, the stress conditions along the planned facility could be assessed.