A rescue helicopter has been deployed to Tasmania's north as a precaution after a major highway was choked by closures due to flood damage to a key bridge.
The Cam River bridge on the Bass Highway at Somerset has been reduced to one lane, after underwater investigations on Thursday revealed flood waters had undermined a pier on the bridge.
The reduction to one lane will cause lengthy delays and it's not known when it will be restored to two lanes.
There's been long delays on the section of road since Thursday afternoon, with some motorists reporting their journey was taking hours.
Infrastructure Minister Michael Ferguson said the situation was being dealt with urgently, and the department was working with engineers to get the bridge fully open as soon as possible.
"We've had some severe damage done to that bridge, we can't repair it immediately, we're going to work very hard over the weekend, to do our best to make it open as soon as possible," he said.
Mr Ferguson expected the bridge would be fixed within days but would follow engineers' advice.
"We're not in any position to cut corners on safety," he said.
Mr Ferguson said the new Cam River Bridge, scheduled for completion in late 2023, would offer Tasmania a better long-term solution.
"We're building a second bridge right now. It'll be better, higher, with longer spans, and it will also be wider, and it'll be more flood resilient," he said.
"But it's a very important fact for me that we maintain network resilience so that if ever traffic disruptions do occur in the future, that we've got backup plans."
Labor health spokesperson Anita Dow said travellers had been left stranded on the side of the road for hours and called for urgent action.
"The government must outline its plans for emergency services and how the hospital will be accessed under such circumstances," Ms Dow said.
"It's not until something like this happens, I think that you realise the impact that such a significant change to access can bring, and access to emergency services is absolutely critical, and we need to understand what's been put in place by the government and how people will be able to access emergency services.
"Minister Ferguson and the government [have] known of the issues with the Cam River bridge for quite some time but yet the Liberal government has failed to come up with a contingency plan."
Helicopter sent north just in case
Ms Dow said even with the new bridge being built, there was merit in maintaining the current bridge as a secondary access point.
"We need to be thinking past this emergency point about the future and how we futureproof access across the Cam River," she said.
Mr Ferguson said Ambulance Tasmania deployed a helicopter to the north to provide additional support if needed.
"Emergency vehicles will always get priority treatment in respect of the queuing of vehicles, and we have not just machine-based traffic management at the bridge on both sides, but also human traffic controllers who can allow emergency vehicles to take priority, as is of course expected," he said.
Bridge 'sagging in the middle'
Murchison MLC Ruth Forrest said the issue would have a major impact.
"We've got thousands of heavy vehicles [to] come out of the north-west region with freight and produce ... we've got people requiring emergency healthcare on the other side of the bridge — that's all beyond that bridge," she said.
"We've got students and teachers needing to get to school on either side of the bridge, they often live on the other side of the river to the school they go to.
"This is a crucial and vital link and the only bridge across the Cam River in the area.
"The locals have campaigned for many, many years for a second bridge for situations such as this."
She said the bridge was "sagging in the middle".
"I've just had a call from one of my constituents that has driven across it to say there is a visible sag in the bridge," she said.
"I have deep concern about putting school buses full of children on it.
"I certainly have concerns about heavy vehicles going across."
Mr Ferguson said he had been advised there were no special restrictions needed in relation to weight on the bridge.
Ms Forrest suggested having buses at either side of the bridge and walking students and passengers across the nearby rail bridge.
"It's not an ideal solution but it saves them having to travel two hours on a loop which is the shortest route that's available at the moment," she said.
"And not an easy drive, it's through Hellyer Gorge, which also has some flood damage."
For those that needed emergency medical help she suggested a helicopter being stationed in Wynyard to transport people to Burnie.
"There's also health workers who work on the western side of the river that will have real difficulty in getting to work in Burnie today to deliver oncology services and all those other really important health care services that we all rely on," she said.
Department working to restore bridge
Some schools in the area asked students to stay home on Friday, while some school bus services have been cancelled.
"This is the last two weeks coming up of senior college for year 11 and 12 for the students that attend Hellyer College and Marist College," Ms Forrest said.
"These students have been severely impacted by the COVID issues already in their senior college education. We need to make sure we can get these children across the bridge or across the river safely."
Leon Smith from the State Emergency Service said last week's flood has caused extensive damage around the state.
"This is just an unfortunate circumstance whereby the flooding in the riverine system has exacerbated and undermined an area of that bridge," he said.
"It just shows the power of floodwaters and the consequences that we can see from such events."
