Some residents claim they weren't given much warning before the Maribyrnong River burst its banks early this morning, as suburbs in Melbourne go underwater just a short distance from the CBD.
Doorknocking in Maribyrnong, Melbourne, got underway at about 4am-5am today, with people being told to leave immediately as their homes were under threat.
But the SES says warnings have been in place for days.
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"We've known for several days now the Maribyrnong River was going to be a risk and we've had a watch-and-act warning out for several days now on that river and houses were doorknocked there a couple of days ago to alert residents as to the potential," Tim Wiebusch from the SES said earlier today.
"Now we're starting to see the major flood level being reached."
The Yarra River also is bursting its banks, Wiebusch said, though it wasn't expected to rise as high as the Maribyrnong.
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Aerial shots show the rising waters moving up to houses in the Maribyrnong area and surrounding suburbs, just kilometres from the Melbourne CBD, and even threatening to inundate Flemington racecourse.
Homes, shops, service stations, pubs and even stables have been subject to the deluge.
Emergency services are carrying out rescues, including via boat, of people who have been stranded in their houses by the rapidly-rising river.
SES Emergency Management Commissioner Andrew Crisp said the swift rise in the Maribyrnong was due to a combination of 150mm of rain falling upstream, combined with shifting tides.
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Relief centres have been opened in the area, including the Maribyrnong Community Centre, for people to head to after they've left their homes.
Crisp said he was hopeful the floods would ultimately recede fairly quickly, but that could still see people barred from returning home for 24 to 48 hours.
The flood is expected to peak later this morning.
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Residents say they've been caught out as flood levels rise higher and faster than expected.
"We got a knock on the door about 5am this morning to get out of there," one man told Today.
"Didn't expect it to get this high. But it doesn't look like it's going to stop any time soon."
