Great Ocean Road at risk from surging sea

Key sections of the Great Ocean Road are at risk of being washed away, raising safety fears and calls for the Andrews government to reroute parts of the world-recognised tourist road.

New studies of dramatic beach erosion around Apollo Bay over the last two years highlight the mounting problem of erosion, flooding and sea level rise along Victoria's coast.

Apollo Bay resident Peter Fillmore: Drastic action will soon be necessary.Credit: Jackson Hayat

In a report to the State government released exclusively to The Age, leading coastal geomorphologist Neville Rosengren and engineer Tony Miner recommend urgent action to protect the foreshore of Mounts Bay next to Apollo Bay, after major erosion there in 2017.

They warn the national heritage-listed road could be “compromised” within five years.

A second report on erosion at Apollo Bay by engineers GHD also recommends the eventual “realignment” of the road outside township areas at Apollo Bay. It notes that five metres of erosion at Apollo Bay beach during a June 2018 storm put the road “at risk”.

The studies point to erosion at critical levels at the very time the state’s south-west is hosting ever greater numbers of visitors, now more than five million a year.

Damage at the Tuxion Road car park in Apollo Bay in June 2018.Credit: Sally Cannon

Similar problems are being faced along the wider coast, from Port Fairy in the south-west to Inverloch and the Ninety Mile Beach and Lakes Entrance in the south-east and east.

The state government commissioned the Rosengren/Miner report to understand the causes of the erosion in 2017 at Mounts Bay – also known as the Apollo Bay back beach – that stripped the beach of sand including thousands of tonnes trucked in to act as a buffer for the foreshore.

The government has spent hundreds of thousands of dollars ‘nourishing’ beaches at Apollo Bay and Mounts Bay in the last few years.

But Mr Rosengren and Mr Miner found that the 2017 erosion was not caused by “extreme or unusual” conditions. “There was no single, large scale event that stood out,” Mr Rosengren told The Age. “There is something general and widespread in time at Mounts Bay.”

The findings raise the prospect that rising seas due to climate change are now proving a real problem for vulnerable coastal locations.

Mr Rosengren said rising sea levels contributed to the erosion at Mounts Bay.

“You’re witnessing the effects of a complex of processes of which sea level is one,” he said.

The Intergovernmental Panel on Climate Change’s (IPCC’s) current projection for sea level rise, based on high emissions, ‘business-as-usual’ scenario, is almost 90 centimetres by the year 2100, relative to an average sea level for the period 1986-2005.

That projection will be updated, most likely upwards, in the IPCC’s special oceans report due for release this year.

Other peer-reviewed studies have forecast a much steeper rise in sea level by 2100.

The road to Apollo Bay.Credit: Rebecca Hallas

The Rosengren/Miner report says that “nourishing” beaches with relocated sand is no long-term answer to the risks to the Great Ocean Road at Mounts Bay, where the ocean is just metres away at high tide.

They say that engineered structures (sea walls of some form) are necessary if the road is to be protected in its current location.

“Government will have to look at building a (protective) structure in Mounts Bay, otherwise the Great Ocean Road will be severely compromised,” said Mr Rosengren.

While possible, realignment of the road would be difficult and expensive at Mounts Bay because the Barham River runs along the landward side of the road, making the area also susceptible to flooding.

The report by engineers GHD - commissioned after a June storm washed away part of a coastal walkway and car park at Apollo Bay - recommends the government consider options including building walls out into the sea (groynes), and the costly realignment of the Great Ocean Road in some places.

The state government is consulting the local community about options, and decisions are yet to be made.

A quandary for all concerned is that sea walls of any form will alter the character of a coastline renowned for its rugged, natural beauty. Sea walls also interfere with the coast’s ecology and its ability to naturally replenish itself.

Bankrolled by public donations, the 243-kilometre Great Ocean Road was built by World War I veterans between 1919 and 1932 as a memorial to soldiers killed in the war, and to open the south-west coast to tourists and daytrippers. It was built as close to the ocean as possible.

Illustration: Matt GoldingCredit:

Experts say that the iconic road was always going to face challenges from the sea – even if only once every 50 or 100 years – because it was built on primary dunes.

However, climate change and sea level rise increase the likelihood, frequency and ferocity of such challenges.

Peter Fillmore is a leader of local community group, the Otway Forum. He describes Apollo Bay, the southernmost township on the mainland, as “the Australian front line for climate change, sea level rise and storm surge increase”.

He has surfed the beaches in the area for 45 years and is a reluctant supporter of construction of groynes as a medium-term option to protect his beloved coast.

Erosion at Apollo Bay.Credit: Jackson Hayat

Mr Fillmore said more drastic action will soon be necessary but that governments, especially the federal Coalition government, are failing to take the lead on climate change and sea level rise.

He pointed to the October announcement by local federal MP Sarah Henderson, of millions of dollars for infrastructure work around Apollo Bay including $5 million for a new two-kilometre coastal walkway to Skenes Creek, an extension of the existing stretch of the Great Ocean Walk out of Apollo Bay.

The announcement came after the existing path partly washed away in the June storm. “They’re in denial about climate change and sea level,” said Mr Fillmore.

“The new walkway to Skenes Creek won’t be able to connect to the current walkway because the current walkway continues to wash out each winter,” said Mr Fillmore. “They’re spending $5 million on a walk to nowhere.”

The Age has sought comment from Ms Henderson

Victorian Climate Change Minister Lily D’Ambrosio, said: “Sea level rise is already considered in our long-term planning for the coast and we’ve invested more than $33 million to prepare for its impact.

“We know that climate change will cause rising sea levels – that’s why Victoria is on the path to net zero emissions by 2050.”

The state government has also committed to establishing an authority to oversee planning and management of the land and seascapes along the Great Ocean Road.

A Victorian Department of Environment Land Water and Planning spokesperson said accounting for sea level rise was now "embedded" in the Victorian planning system.

The Age has sought an interview and comments from federal Environment Minister Melissa Price about the Morrison government’s policies on, and plans for, sea level rise.