Melbourne Water will update its flood modelling for the Maribyrnong River after more than 500 homes and businesses were unexpectedly inundated.
The organisation copped criticism in the wake of the October 2022 floods, with residents in the city’s northwest saying they did not receive adequate information or warning about what was to come.
Melbourne Water, in a 36-page submission to its Maribyrnong Flood inquiry, admitted the river rose faster than its modelling had predicted.
At Chifley Drive in Maribyrnong, the river rose from a minor flood level of 1.7 m at 4.25 am on Oct. 14 to a major flood level of 2.9 m two hours later.
Melbourne Water last commissioned modelling for the lower Maribyrnong River in 2003.
The organisation confirmed it would use the recent flood’s river heights and flow rates data to update the modelling.
“This allows for the models to be calibrated with more accuracy,” the submission read.
Melbourne Water is yet to detail the impact of the Flemington Racecourse flood levee, saying a complex hydraulic and hydrologic model would need to be completed.
The grounds of the Melbourne Cup track remained clear as the surrounding area flooded, thanks to a 2.5 m wall built in 2007.
The water body is continuing to investigate the impact of the wall.
“This modelling takes time and has not been possible in the period available for submissions to this review,” the submission read.
“It is usual for modelling of this kind to take at least 12 months to complete.”
The inquiry on Friday released the 62 submissions it received from residents, councils and organisations.
The review panel will consider that evidence and prepare a report, which will be submitted to Melbourne Water in August.
The report will then be handed to the Victorian government before it is released publicly.
