19/05/2020

(AU) Erosion From Surging Seas Threatens Roads, Homes And Beaches

Sydney Morning HeraldRoyce Millar | Benjamin Preiss | Miki Perkins

Surging seas have battered beaches and rattled communities along Victoria’s 2500 kilometre coastline since Easter, raising confronting questions about how to respond to rising oceans and rapid erosion.

High tides, big swells and storms have combined to pummel dunes and roads as anxious communities face the reality that homes and businesses may soon be at risk.


Coastal erosion in Inverloch, Victoria, is threatening businesses and homes.

At erosion hotspots like Inverloch, 150 kilometres south-east of Melbourne, and Apollo Bay 200 kilometres to the south-west, emergency defences including sand walls and fences have been swept away as debate intensifies over whether to defend assets or retreat to higher ground.

Despite the state’s ‘stay at home’ rules, imposed due to the coronaviruFs pandemic, anxious locals have gathered in numbers at beaches around Inverloch to watch waves tear at sand dunes, trees, roads and piers.

The main focus of concern is the low-lying road east toward Cape Paterson which has twice been closed as waves crashed onto bitumen and the sea-change dreams of nearby residents.

Last week traffic faced long delays as the government trucked in 7000 tonnes of boulders in a desperate bid to fortify the threatened stretch of road before winter. The new works came just weeks after an emergency 500-tonne rock wall was undermined by erosion.

A rock wall being built to try and halt erosion at the beach in Inverloch. Credit:Royce Millar

Locals are also anxious about the Inverloch surf life saving club which is under threat since erosion pushed the shoreline back 60 metres over the past eight years.

The latest defence for the surf club is a 70-metre emergency wall of ‘geotextile’ sandbags. While the bags are supposed to last up to 10 years, some have already been damaged by the relentless thrashing by waves and debris.

So dramatic is the erosion that the local conservation society has warned that the remaining sand dunes along the surf beach could be lost within 18 months, further exposing the coast road and nearby housing, and highlighting the much bigger challenge of sea level rise.

In September the Intergovernmental Panel on Climate Change warned that inaction on climate change would likely result in sea level rise of 1.1 metres by 2100 – up from the 2013 projection of more than 90 centimetres. Without action, the seas will be five metres higher by 2300.

While the IPCC says cutting emissions is the number one priority for dealing with rising sea levels, some change is already locked in. How we adapt is an increasingly urgent question.

As anxiety grows at Inverloch, so too has pressure for a massive rock wall along the entire length of the surf beach.

Experts query the wisdom of such walls, pointing out that they are incompatible with wide sandy beaches, and that erosion is made worse at either end.

Local environmentalists say the long-term solution is to tackle climate change. Meanwhile, a retreat to higher ground may be necessary.

Aileen Vening is a retired geography teacher who has spent almost a decade studying the causes and impacts of erosion along the Bass Coast. She is calling on her own community, and governments, to recognise that the dramatic erosion at Inverloch is not just a local phenomenon.

“We’ve got these issues everywhere on the coast. They’re not going to go away because we built a few rock walls here and there.”

Erosion at Inverloch is now threatening the coast road and nearby homes

While erosion at Inverloch is part of the natural cycle of shifting sand at the mouth of the Anderson Inlet, Bass Coast Shire has no doubt the extent of change is due in part to climate change and rising seas.

It is one of more than 30 Victorian councils to have declared a climate emergency since 2016.

“My view is that sea level is definitely rising, the climate is changing and the seasons are shifting,” said mayor Brett Tessari. “We have to do what we can to reverse some of the damage we’ve created.”

He acknowledges the “cries” from the community for a wall along the length of the sandy surf beach at Inverloch. But he is also aware that a rock wall would likely result in the disappearance of Inverloch surf beach.

The state government is now working on a longer-term solution for Inverloch through a local hazard assessment study in partnership with the council and community.

Decisions about defending or retreating, walls or beaches, are also especially topical at Apollo Bay which, like Inverloch, has been battered by angry seas since early April.

As The Age revealed in 2019, experts have proposed the inland re-routing of the heritage-listed Great Ocean Road at Apollo Bay amid warnings that it is at risk of being washed away in the next few years.

The government has resisted the re-routing push and has instead focused on building sea walls and other defences and supports.

Local surfer Peter Filmore said short-term government responses had failed to address the long-term reality of rising sea levels.

“Seventeen reports have been completed in the last 30 years on sand movements around Apollo Bay but no long-term planning is in place yet,” said Mr Filmore, also a member of the local Otway Forum.

He said governments were not being realistic about erosion, pointing to Colac Otway Shire’s plan for a $5 million coastal walking track from Apollo Bay to Skenes Creek – a track, he said, that was almost certain to be washed away.

Environmental lobby Friends of the Earth has worked closely with community groups along the Victorian coast.

Climate spokesman Leigh Ewbank said people were connecting the dots between burning fossil fuels, climate change and local impacts. “They say governments need to do more to tackle the climate crisis, it can’t just be Band-Aid fixes of dumping more rock and moving sand around.”

Environment Minister Lily D’Ambrosio said the government was assessing the erosion caused by recent “unexpected storm activity”.

She said coastal managers would install more warning signs and close sections of the foreshore as required.

Ms D’Ambrosio said the Victorian government had spent $60 million on a range of coastal and marine projects, including sand renourishment and reinforcement.

“Our precious coastline is facing significant climate challenges and we’re working hard to address this in the short and long term,” she said.

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