STIRLING’S PLANS TO BATTLE EROSION AND RISING SEA LEVELS

By April Shepherd, Editor, Council Magazine

City of Stirling, located in Perth, is picturesque – with blue oceans and infamous beaches lining its coastlines –but unfortunately the threat of erosion and rising sea levels is looming on the region’s horizon. This is why Council has released a new long-term plan, designating high risk areas and outlining how the City can save its critical assets.

Climate change is no longer a future threat or a disaster movie-esque mass tragedy, – but a profoundly real reality that has crept into Australia's everyday life, requiring action and proactive planning.

As a coastal region the City of Stirling has the potential to be largely affected by climate change, this is why the Council is beginning to implement plans for the future and present day.

To manage the risks associated with erosion and rising sea levels, Stirling Council has released a new draft report outlining the areas of the region that may be worse affected, with appropriate measures for the City to adopt.

The Coastal Hazard Risk Management and Adaptation Planning (CHRMAP) report is a strategic, long-term plan that aims to guide the Council’s response to existing and potential coastal hazards.

City of Stirling Mayor, Mark Irwin, said the report was needed due to the escalating coastal hazards in the region and to further existing initiatives through scientific research.

“We really need more scientific knowledge and a better understanding of the real facts, understanding what is just storm damage, what is cyclical and what is the real long-term effects of climate change,” Mayor Irwin said.

“Then we have something concrete that we can go to State or Federal Governments with to seek further funding, to ensure that we're able to adapt and protect for the future.”

Key Recommendations

The report makes multiple recommendations such as required future works, which areas where retreat from the coast is more appropriate, and which will be protected or mitigated in the short term.

Some of these recommendations include:

∞ Creating an ongoing coastal adaptation and management fund

∞ Inspecting long-term adaptation measures for land expected to be at risk of coastal erosion by 2122, which contains major infrastructure such as:

» West Coast Drive

» The Esplanade, Scarborough car parks and the Whale Playground

» Scarborough Amphitheatre

» Scarborough Beach Pool

» Scarboro Surf Lifesaving Club

∞ Immediately implementing soft protection measures (dune restoration and sand-fencing)

∞ Researching possible engineered solutions to keep nourishment in place

∞ Initiating a long-term coastal monitoring program (this will include storm and metocean monitoring, coastal asset condition assessments and geological risk monitoring)

∞ Undertaking targeted nourishment of beaches

“The report also talks about longer term options and the investigation that we have to do in terms of changing the shape of the coastal situation, such as sea walls or groynes, and understanding what the ongoing risk of that would be,” Mayor Irwin said.

“It effectively talks about what work we have to do, the risk of not doing anything against the risk of doing something, and gives us a basis to advocate for funding support we will need.”

Mayor Irwin said the report also breaks down each section of the coastline and studies areas that may not be in issue in the short term, but will be 10, 25, 50 or 100 years. .

AT-RISK ASSETS

Multiple community assets in the City of Stirling are at risk of being eroded or inundated over the next 100 years, including beaches and dunes, jetties, footpaths, community amenities and major infrastructure.

Mayor Irwin said that the region has a long history of erosion, with Council tackling the issue since 2010, following vicious storms in the Watermans Bay and Mettams Pool area. While works were done directly following the storms in 2010, such as sandbagging protective walls and sand nourishment/ replacement works but it was not enough.

“We've been working on some basic risk mapping and trying to understand those 10, 25, 50 and 100-year horizons for a number of years,” Mayor Irwin said.

“A couple of years ago we did significant consultation around those Mettams and Watermans areas. That was around the usage for the residents and trying to understand what their expectations were.”

According to Mayor Irwin, one of the biggest challenges throughout the report creation process has been that “everyone's got a view, and there seems to be a lot of differing ones”.

Community Feedback

The erosion in the area has worsened, with locals and stakeholders providing Council with crucial feedback regarding the local environment and how it has changed over the years.

“There's a lot of combined knowledge up and down the coast,” Mayor Irwin said.

Mayor Irwin said it is hard to differentiate the effects the community has seen in recent years between climate change and just a particularly bad storm season, with 2022 bringing intense weather for much of the East Coast of Australia and Perth.

“Part of this report is trying to understand what is just one of those one-in-a-hundred-year storms,” Mayor Irwin said.

“We had a lot of damage this winter, with water coming up and sweeping out access ramps right up and down the coastline, washing fence lines down into the ocean, creating dangerous situations with wire and copper logs floating in the ocean."

Urgent Action Needed

With some areas at immediate risk, such as the aforementioned Watermans Bay and Mettams Pool, Council has a busy future ahead.

Council’s next steps will include assessing what assets can be saved, and for how many years.

“As we look ahead to 50 and 100 years, we start to understand how much of those buildings and playgrounds and access ramps will be under threat,” Mayor Irwin said.

For Mayor Irwin, the future of his region doesn’t just rely on community feedback and implementing the recommendations in the report, but also on advocacy and availability of funds.

“It is a nationwide issue and there needs to be investment to assist local governments in not only being sustainable for the future with their sustainability programs, but also protecting and mitigating risk along coastlines,” Mayor Irwin said.