Melbourne Water, as part of its Housing Statement Roadmap, is progressing a new risk-based approach to assessing flood risks associated with urban development, via the Floodplain Development Impact Assessment Practice Note. Developed in collaboration with the Department of Energy, Environment and Climate Action (DEECA) and guided by the Urban Planning and Development Strategic Collaboration Group (UPD SCG), the Practice Note is now being implemented with an evaluation phase.

As Greater Melbourne’s floodplain manager, Melbourne Water (MW) has responsibilities under the Water Act (1989) to provide flood advice and establish controls on developments to minimise flooding and flood damage. We continue to meet requirements that ‘there should be no detrimental impacts to nearby properties, particularly properties downstream’, as per the Department of Energy, Environment and Climate Action (DEECA) 2019 Guidelines for Development in Flood Affected Areas.

To balance risk mitigation with responsible urban growth, the new Practice Note is intended to support a more granular flood risk management approach. It establishes:

• High-level impact assessments to determine if further flood analysis is needed
• A review of existing conditions to evaluate potential effects beyond the development site
• Clear flood tolerance thresholds, tailored to different land types
• Additional data gathering, including flood modelling and floor level surveys, to enhance decision-making
• An iterative compliance process, ensuring projects meet flood risk requirements while supporting housing growth.

Staged implementation will begin with a three month evaluation phase on selected urban development projects and state-led initiatives in collaboration with the Victorian Infrastructure Delivery Authority (VIDA). This will allow Melbourne Water to examine the breadth of its applicability and ensure there is no material risks associated with the permissible afflux. By identifying data gaps, ambiguities or practical limitations, critical insights will be identified, before any broader application.

Melbourne Water remains committed to working with government and industry partners to improve flood risk management strategies, ensuring a balanced approach that supports housing development while safeguarding communities. We may make further refinements to the Practice Note following the initial evaluation phase and will develop technical guidance resources to support internal application processes. We will ensure industry is kept informed of these updates and encourage everyone to sign up to our Planning and Development Hub, so we can keep you in the loop.