With Victoria’s population rapidly increasing and urban growth boundaries expanding, the Victorian government is looking at ways to better manage stormwater runoff, protect state waterways and strengthen integrated water management.  

The Department of Energy, Environment and Climate Action (DEECA) required an informed analysis of the most effective solutions for meeting stormwater harvesting targets across different development types and scenarios. We were commissioned in partnership with Frontier Economics to assess the economic and financial feasibility of the interventions required to meet stormwater flow reduction, and identify and evaluate a range of options for achieving flow reduction targets for different development types. 

Our water engineers collaborated with our data scientists to create a digital solution to optimise the stormwater management modelling tool (MUSICX) to test whether the flow targets could be met and the cost of the various interventions. This allowed the team to examine a multitude of development scenarios, to the most optimal stormwater runoff reduction measures for each scenario. This innovative digital solution enabled our water engineers to efficiently assess and communicate the effectiveness of stormwater management measures to DEECA.  We were able to present optimal methods and enable more nuanced and informed decision making to promote resilient stormwater systems. 

Water engineering and integrated water management

Our integrated water management experts looked at opportunities to protect Victorian waterways and safeguard water infrastructure and systems.  

To test new targets for stormwater management, we needed to explore the feasibility of stormwater runoff reduction measures in different urban contexts.  

Our team identified 460 possible development scenarios. For each development scenario, we defined the set of water sensitive urban design interventions available, and plausible upper and lower limits for the sizing of each, considering space constraints, integration with landscapes and synergies with local water demands. 

Using digital tools to model the best outcome

A total of 13,000 model runs were automated and presented in a PowerBI dashboard, a user-friendly format which allowed data to be clearly interpreted and inform better decision-making around stormwater management. 

To deliver these results, our data scientists developed Python code to automate and optimise MUSICX model runs. Using Machine Learning, the model intelligently found the most effective and efficient combination of interventions which achieved harvesting targets. The algorithm adhered to the potential stormwater measures and constraints set by our integrated water management experts for each of the 460 possible development scenarios.   

We invested resources into researching innovative digital technologies to increase the efficiency and effectiveness of engineering solutions. 

The innovative modelling approach used by Arup means we are confident that any future policy or regulatory reform has been informed by hundreds of possible scenarios and the best available information.

Maggie Xipolitos

Senior Policy Officer, DEECA