The Stormwater Management Plan is designed to substantially reduce the number of properties within the catchment that would be affected by very large flood events, up to and including a 100 year ARI flood.
A 100 year ARI (Average Recurrence Interval) flood is a flood that will occur statistically on average once every 100 years, and has a 1 in 100 (1%) chance of occurring in any given year. It is the most commonly applied standard in Australia for providing an acceptable level of flood protection for the community.
Approved by the Stormwater Management Authority in February 2017, the SMP details construction of a number of flood mitigation works across the catchment, as well as non-infrastructure measures to help reduce the impact of major flooding. Important environmental and community benefits are also identified including:
- Improved quality of stormwater discharge into marine receiving waters;
- Beneficial reuse of stormwater, particularly for greening of urban open space areas;
- Creek rehabilitation and protection of biodiversity; and
- Improved recreational amenity in open space areas traversed by watercourses.
The works present urban renewal opportunities to enable communities to better use the land corridors through which stormwater is designed to be conveyed, ie linear parks, wetlands and shared use paths.