Flood Risk and Stormwater Modelling

Between 2019 and 2020, Grace GIS delivered specialised flood risk and stormwater modelling support to Melbourne Water, providing high-accuracy spatial analysis to improve understanding of hydrological behaviour across urban catchments. Using detailed elevation models, flood extent datasets, and advanced geospatial interrogation techniques, we generated insights that strengthen stormwater governance, flood hazard identification, and long-term resilience planning.

As part of the Melbourne Urban Stormwater Institutional Arrangements Review (MUSIA) in 2020, we conducted comprehensive spatial data analysis for a 150-hectare catchment model. This work included evaluating hydrological connectivity, verifying drainage alignments, assessing stormwater pathways, and analysing land-use influences on runoff. The results informed a major review of metropolitan stormwater governance, supporting evidence-based recommendations for improved management of urban water systems.

In 2019, Grace GIS developed water-velocity estimation products by integrating flood extent mapping with high-resolution terrain models. Through gradient analysis and hydraulic approximations, we identified areas of high-velocity flow—critical information for understanding erosion risks, infrastructure vulnerability, public safety hazards, and emergency response planning.

Together, these projects provided Melbourne Water with robust, science-driven datasets and modelling insights that enhance the region’s ability to assess flood behaviour, mitigate stormwater risks, and plan for future climatic and hydrological challenges.