The Victorian Transport Association warns money put aside in the budget for road maintenance and upgrades were budgeted before the floods.
"These roads need to be reconstituted, reinstated and reinforced and we need additional money to be able to do that," VTA CEO Peter Anderson said.
"And if we don't realise that, if we think we're just going to rely on the old budget, the current budget- then we are just going to be kidding ourselves.
The VTA has estimated fixing the state's "flood devastated transport networks", will cost between $500m and $1billion.
Mr Anderson said although it was mostly state roads that had been damaged, the issues would be felt nationally.
“We are already seeing evidence of how national supply chains have been compromised with farmers struggling to get their goods out of regional Victoria to the ports and on to interstate and international markets,” he said.
“The flow-on effect will be felt leading up to Christmas in the form of higher consumer prices and a shortage of supply.
- VTA CEO Peter Anderson
The Department of Transport notified the freight industry on Wednesday, that 442 roads were currently closed across the state.
Areas most impacted include those along the Murray and the Goulburn Rivers.
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