Exclusive: Holidaymakers and locals in Wye River are beginning a massive clean-up after "an extraordinary rainfall event" triggered severe flash flooding.
More than 180mm of rain fell into catchments at Mt Cowley, inland from Lorne, within a six-hour span yesterday, leaving caravan parks in ruin and dozens of vehicles destroyed.
A child was airlifted out of the flood zone to hospital after becoming injured when they climbed onto the roof of a building to seek safety, Emergency Management Commissioner Tim Wiebusch said.
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Families were forced to flee to higher ground with just the clothes on their backs, with many claiming flood alerts only came through once towns had already been engulfed.
"By the time I got a notification that there was a flood happening... the flood had already happened," Wye River General Store and Cafe manager Shaun McKinlay said.
The Bureau of Meteorology says a severe thunderstorm warning was released at 11.57am, followed by a watch and act for potential life-threatening floods at 12.58pm.
As many as 300 people were displaced by the weather event, with 60 of those receiving support at an emergency relief centre in Lorne.
"Yesterday we saw an extraordinary rainfall event unfold across the Great Ocean Road with 186.2mm recorded at Mt Cowley, inland from Lorne, in the 24 hour period to 9am," Bureau of Meteorology Hazard Preparedness & Response Manager Diana Eadie said.
"That well and truly exceeded the previous record at that particular location, which was 123.2mm recorded back in 2021."
'Never seen anything like it': Campers described scene of destruction
Charlotte Armstrong and her family were staying in a camper trailer one site above the Cumberland River when the river surged around 12.30pm.
"I looked at the river, we were just getting lunch out and I said, 'Oh, the river is flowing pretty fast', and probably like three minutes later it had risen up to our site," Armstrong said.
"We knew there was rain coming, so we tightened our annexes and prepared for that, but nothing like what happened. It happened just so fast.
"We were just trying to take all the stuff from the riverside, but it was so strong and so fast, there were huge trees coming down the river."
Holidaymakers have been told they can't return to salvage their belongings for at least another 48 hours, leaving many unsure about the extent of the damage.
"With the heavy rain that came in, we have no idea what's left," she said.
Armstrong believes her Subaru Forester was destroyed in the flood, but the family still doesn't know what happened to their camper trailer or the family car.
"We've been going there for over 20 years, we've never seen anything like it. There's been flooding but yeah, nothing like that," she said.
Another Cumberland River Holiday Park camper, whose caravan and car were swept up in the rapids, said the water reached waist height within 10 minutes of the deluge.
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"We were up the other end of the caravan park, further away from the entrance, so we were some of the first people to get affected," the teenager, who did not want to be identified, said.
"I managed to get most of the stuff out of the caravan... everything that was valuable.
"They're still plenty of bedding and like cutlery and stuff in there but we got all electronics and stuff out."
The caravan still has't been recovered, he said.
"It'll be in the ocean somewhere, probably, or on the beach somewhere.
"It might be jammed onto the bridge with the other cars. We don't know."
Campers who were fast enough fled to a nearby hill behind the park, while others had to wade through waters and jump on top of roofs to find safety.
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"Lots of people you know couldn't make it there in time, so they just got on top of like cabins or on top of the reception office," the man said.
"A friend of mine helped some older folks get onto the top of the reception."
A man in his 60s was later winched from the reception roof due to an existing injury that prevented him from getting down.
The 19-year-old's family, who have been holidaying at Cumberland River Holiday Park for 16 years, had evacuated the area just last week as bushfires in the nearby Otways raged through bushland.
"I went into autopilot, honestly. I don't think I felt any fear until afterwards and then I thought it was just like a profound sense of exhaustion," he said.
"I think the main thing that's shaken us up is like, if it happened at night, there would be almost certainly fatalities, like it was so quick."
More severe storms could be on the way
The threat of the flooding has now reduced, but people in the area are being urged to look out for hazards including debris, fallen trees, powerlines and damaged roads.
The Great Ocean Road remains closed between Skenes Creek and Lorne, as authorities continue to assess road damage.
The Erskine River Bridge and Wye River Bridge have both been cleared by the Department of Transport.
But cars and debris remain piled up against the Cumberland River Bridge, meaning authorities have been unable to give it the green light to reopen the Great Ocean Road.
Wiebusch said it was too early to predict when the Great Ocean Road would be fully reopened to traffic.
"If you are heading down into that area this weekend, be aware that there are significant detours in place," he said.
"If you don't need to be going beyond Lorne, then at this point our best advice is please don't travel beyond Lorne."
Local governments are also on scene to help coordinate the clean-up.
The risk of heavy rainfall is now confined to the far east of the state, but severe storms could return early next week.
"We will see a return of the potential for severe thunderstorms to western parts of Victoria on Monday, extending further to the east on Tuesday." Eadie said.
That is expected to be followed by heightened fire danger next weekend.
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