In partnership with Glen Eira City Council, we’ve commissioned several studies into options for mitigating flooding from the Koornang Main Drain, which services the suburbs of Ormond and McKinnon.

Latest investigations

Melbourne Water has been investigating options for the drain since 2011, with the most recent studies completed after discussions with residents last year. 
The studies investigated additional locations for a retarding basin and alternative drainage options. They are referred to as the: 

  • ‘Pit study’ – a local study of the Cadby Avenue area
  • ‘Floodplain study’ – a study of a larger area covering the catchment for the Koornang Main Drain.

Existing drainage pit in Cadby Avenue
Existing drainage pit in Cadby Avenue








Summary report

The following report summarises these studies, their main findings and next steps. If you have any questions about the information contained in this report, contact us.

Findings and next steps

The studies determined that:

  • Of the possible locations for a retarding basin, a single storage basin was not a viable option. The volumes available would either not provide enough storage to prevent flooding, or would make the open space no longer usable for its current purpose.
  • Most drainage options would move the flooding further downstream, which would then increase flood risk.

Melbourne Water and Glen Eira City Council will continue to work together to assess options.

Further assessment has been identified on one option: construction of a direct pipe from Koornang Main Drain to Port Phillip Bay. This option was previously considered unviable due to the very significant construction costs but is being reviewed in light of new understanding of flooding at this location.

More information

While we can’t stop floods from happening, we can work together to plan for and manage the risks, build community preparedness, and reduce the consequences.

Learn how to prepare for flooding.

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