What’s best for Victoria’s eroding coast?

James Cotton started the Save Pt Lonsdale Front Beach Facebook page. Photo: Paul Boyd

When the tide is high and a swell pushes in through Port Phillip Heads, it wraps around the headland at Point Lonsdale and smashes into the rock-wall at the front beach. Surfers, enjoying the only consistent break inside Port Phillip Bay, sometimes catch a wave rebounding off the wall, such is its force on impact. At these times, the beach, the centrepiece of this small coastal town, is all but submerged.

In January, a petition was placed across the road from the Point Lonsdale shops. It described the merits of five additional rock or timber walls, known as groynes, being constructed as the preferred approach to trapping and keeping sand on the beach. The original sea wall was built in the 1900s and even the oldest memories of the beach include some form of groyne extending from it at right angles into the bay.  Locals, having clearly articulated their desire for more groynes to be constructed, have created a swell of momentum to ensure it happens.

The petition calling for more groynes at Point Lonsdale beach. Photo: Paul Boyd

Coastal processes are complex. Waves, storms, tides and wind combine to create a distinctly unique and highly variable influence constantly shaping and changing the coast.  Introduce increasing storm surges and rising sea levels as a result of climate change, and the task to understand these processes and manage their impacts becomes a formidable challenge. The governance of coastal policy as well as community views on dealing with coastal landscapes in Victoria can be equally complex, and there’s a danger that without a shift in mindset, innovative and environmentally cohesive solutions may be overlooked.

The 2018 Victorian Auditor General Office’s report on the management of Victoria’s coastal assets said that a 0.8-metre rise in sea level by the end of the century (a level based on modelling from the Intergovernmental Panel on Climate Change) will put most coastal infrastructure and assets at risk of inundation or erosion and that the systems in place to manage Victoria’s coastal assets are failing on many levels.

When James Cotton returned to Point Lonsdale after 10 years overseas, the beach he remembered had changed.  He says his children “were not able to swim and surf where he did as a kid” and it was most noticebible when they were “stubbing toes on rocks where it used to be just sand”.  After hearing similar concerns from locals and realising the local council, the Borough of Queenscliffe, was spending hundreds of thousands of dollars each year on patching up the rock wall with Victorian Government assistance, he started the Save Pt Lonsdale Front Beach Facebook page.  Cotton believes the Borough wasn’t interested in discussing a longer-term solution and the result of his campaign, as intended, was Victorian Government agreement to take a closer look.

In 2017, the Department of Environment, Land, Water and Planning (DELWP), based on a report by consultant BMT-WBM, concluded that there was “no current public safety issues or immediate risk to assets due to sand fluctuations at Point Lonsdale. While funds will be directed to manage risks at other locations, maintenance of the Point Lonsdale seawall and groynes will continue as needed.”  The beach, it concluded, was likely to be subject to a slow, long-term decline but the cause of the erosion was unclear. While building more rock groynes along the beach might encourage sand build-up, there was no proof this would work. The department advised that further longer-term monitoring was required.

Fast forward to early 2019 and the Point Lonsdale community has just received the results of a new evaluation process paving the way for further groyne design.  At the community’s instigation, the State Member for Bellarine, Lisa Neville, announced in early 2018 that a new study would be commissioned and consultant Cardno commenced work with a brief specifically to evaluate the construction of groynes for the Point Lonsdale front beach.

One community member involved in seeking a solution believes the fixation of certain members of the community on groynes is leading to solutions more about keeping people happy and less about the science of coastal processes. He says there is a lot of “discussion about the success of obtaining grant funds, which is possibly more a matter of writing submissions that tick the right boxes rather than an identified need”.

Victorian-based Simon Branigan, marine restoration coordinator with environmental non-profit organisation The Nature Conservancy (TNC), believes when it comes to coastal protection there is often a tendency for “communities and engineers to prefer familiar engineering solutions – rockwalls, groynes, breakwaters.  These solutions have their place but they inevitably push impacts further along the coast”.   TNC’s work in this area around the world examines nature’s role in reducing coastal flood risk and building resilience back into the coast.  They are currently implementing projects in most Australian states and in Victoria this includes the construction of three shellfish reefs in Port Phillip Bay aimed at increasing fish habitat and recreational fishing opportunities, improving water quality and reducing wave energy.

The project, initiated by the Albert Park Yachting & Angling Club and supported by the Victorian Government, is as valuable, Branigan believes, for its role in “building knowledge, expertise and familiarity with innovative ways to increase coastal resilience” as it is for the potential environmental benefits.

When it comes to high energy wave environments, such as Point Lonsdale, where coasts are already highly modified with rockwalls and groynes, Branigan acknowledges the difficulties in avoiding traditional hard engineering solutions but notes the importance of considering a system in its entirety.

Importantly the original BMT-WBM report highlighted that the “success of a groyne field is dependent on suitable sand supply, and that by their very nature of trapping sand, groynes transfer a sand loss further downdrift along the shoreline and that such risks needed to be assessed before any work is conducted”.  In an email to Neville noting the absence of an evaluation of possible impacts further along the shoreline by Cardno, the Labor MP responded: “It is always one of the risks with groynes, that it can have an impact further down the shoreline – move the problem.  It is something in the final choice and design we will need to be aware of and also monitor.”

As part of his work as senior environmental engineer with the City of Greater Geelong and his PhD with Melbourne University, Ralph Roob, dissatisfied with short-term coastal erosion solutions, has constructed an artificial off-shore reef near the coastal town of Portarlington.  The 130-metre-long reef, aimed at reducing wave energy, erosion and the increasing threat of inundation to houses, is essentially a series of 0.75 metre high cages filled with rock and recycled scallop shells.  The impacts on sand movement and marine life will be monitored extensively over several years, he says there’s already “signs of sand accumulating on the beach and seagrass establishing in areas sheltered by the reef”.

Portarlington. Photo: Paul Boyd

Roob admits the level of innovation and experimentation applied to this small stretch of coast would be impossible to replicate along all of their managed coastline.  “We have a council budget of a few hundred thousand dollars, most of it goes to emergency and temporary fixes.”  When it comes to Victorian Government funding he says: “We have to prioritise grant applications for assets on their last legs.”  He laments the difficulties in being strategic and innovative but points out “if we think only in terms of hard engineering solutions, they’ll just have to be built bigger and bigger”.

In 2018 DELWP released the new Marine and Coastal Act to simplify and improve coordination of marine and coastal planning and management in Victoria and ensure funding targets the most valuable built and natural assets.

In the same way that the understanding of climate change continues to evolve, so too should the solutions considered adapt to new science and information.  Regardless of what balance new legislation can bring to the governance of coastal management in Victoria, it is the exploration of new ideas when considering solutions, rather than a default to traditional responses, that provides the ability to advance knowledge and respond to the shifting challenges of a changing climate.  Thinking in terms of building resilience into our coasts as a whole, rather than defending them as if from a swelling enemy, can begin to widen the scope of what is possible, and given time and innovation, of what is considered acceptable.