Modelling during the Healthy Waterways Strategy mid-term review to understand likely risks and opportunities in the face of urban growth and climate change (#64)
Rhys A Coleman
1
2
,
Yung En Chee
2
,
Ryan M Burrows
2
3
,
Trish Grant
3
,
Sharyn Rossrakesh
3
- Research and Modelling, Melbourne Water, Docklands, Victoria, Australia
- School of Agriculture, Food and Ecosystem Sciences, The University of Melbourne, Burnley, Victoria, Australia
- Waterways, Biodiversity & Environment, Melbourne Water, Docklands, Victoria, Australia
- The Healthy Waterways Strategy 2018-2028 for Greater Melbourne includes management actions and 50-year targets to improve and maintain habitat of aquatic macroinvertebrates, native fish and platypus. This is underpinned by spatially explicit, quantitative habitat suitability modelling (HSMs), quantitative prioritisation of cost-effective management actions, and a collaborative process with stakeholders. HSMs enabled predictions of current and future habitat suitability for instream biota across the entire stream network with scenarios of climate change impacts and urban growth, as well as mitigation benefits of management actions (riparian revegetation, stormwater harvesting and treatment, removal of fish barriers) in isolation and in combination.
- Melbourne Water’s mid-term review of the strategy used HSMs to evaluate the likely long-term benefits of management actions to date, benefits from the proposed 10-year program plus concurrent urban development, and impacts of climate change using climate projections updated since releasing the strategy.
- New climate projections incorporate plausible futures that are warmer and drier than previously modelled. The HSMs indicated benefits are still expected from management actions to date and the full 10-year program, however, they also suggest some important environmental values are at greater risk, including platypus, river blackfish and ornate galaxias.
- HSMs were a valuable tool for exploring risks and opportunities for instream biota with a range of near- and long-term scenarios. This included identification of climate change vulnerable species and reaches where early mitigating actions are most important. It also highlighted the need to rethink some strategy priorities and identify innovative solutions that broaden our suite of management options.
Download Full Paper