Keeping Melbourne’s suburbs safe during extreme rainfall
Melbourne Water manages more than 200 retarding basins spread across the Greater Melbourne area. These retarding basins provide an important function during most rainfall events by mitigating flooding in downstream areas. Many of these retarding basins also act as a recreational resource for the community, and some hold water permanently to support biodiversity in our suburbs.
During extreme flood events, high intensity rainfall can cause these retarding basins to fill beyond their design capacity. This can present a risk to the downstream community.
Melbourne Water have been forward thinking in managing these risks. HARC and our project partners AECOM, have just completed risk assessments for 23 of the retarding basins. This involved flood hydrology modelling, hydraulic modelling of the potential flood extents, and an assessment of the life safety risks posed by each retarding basin.
Simon Lang, HARC’s project manager said, “This project provided us with a great opportunity to apply the techniques that we’ve developed over the years on large dams, to help Melbourne Water manage the risks presented by the retarding basins within our suburbs.”