GIS-Based Terrain and Network Modelling

Between 2016 and 2022, Grace GIS delivered a suite of advanced terrain and hydrological network modelling projects that strengthened Melbourne Water’s understanding of subcatchment behaviour, stormwater connectivity, and regional drainage performance. Using high-resolution LiDAR elevation models, hydrological conditioning, and network extraction techniques, we produced datasets that support detailed modelling, planning, and engineering analysis across the metropolitan region.

In 2022, we developed an updated subcatchments layer in collaboration with WERG at the University of Melbourne, refining hydrological boundaries with modern LiDAR inputs and improved modelling workflows. This dataset enhances watershed interpretation, supports research applications, and underpins more accurate hydrological modelling across Melbourne Water’s network.

In 2016, Grace GIS created nested subcatchments for Directly Connected Impervious (DCI) modelling, capturing the fine-scale relationships between impervious surfaces and downstream drainage systems. These layers help Melbourne Water assess runoff generation, pollutant loads, and stormwater response across urban environments.

That same year, we also produced a LiDAR-based subcatchment and network model for Melbourne Water’s primary catchment areas. This work included hydrological conditioning, flow-path extraction, drainage hierarchy modelling, and watershed delineation—providing the region’s most accurate representation of natural and constructed drainage networks at the time.

Together, these projects deliver a robust, science-driven foundation for hydrological modelling, stormwater assessment, infrastructure planning, water quality analysis, and long-term catchment management across Melbourne Water’s jurisdiction.