Surf quality at Narrabeen will decline over coming years and decades, according to new research from Griffith University.

Sea levels are projected to rise by about 66cm over the next 65 years at the beach, a popular summer destination for North Shore residents.

The research was commissioned by Surfrider, a not-for-profit beach protection organisation.

Rowan Hanley, secretary of Surfrider’s Northern Beach branch, told the North Shore Lorikeet that Sydney’s Northern Beaches may be “canaries in the coalmine” as climate change reshapes our coastline.

Eroding beaches predicted

The report stated that Narrabeen’s sea level rise and change in swell direction was expected to increase erosion and threaten beach recession in coming years. “Beach erosion is already a problem for this location, and has been for years,” it said.

Precise localised data on the impact of climate change on surf breaks is thin on the ground.

“The Australian coast is quite well studied, especially in urban areas, but surf spots and climate change's effects on surf [aren’t] so much … science is still catching up to climate change,” Hanley said.

But with more information now available, Hanley said local councils and politicians need to start accepting the science.

“Coastal science is incredibly complex and highly localised, so when decisions about coastal management are made we really need to have local councils, state and federal governments working together heeding the advice of coastal scientists.

“At the moment we don’t, and this is a real concern on the Northern Beaches, where we are a sort of hotspot for climate chaos when it comes to storms and flooding. We’re in trouble and there’s a lot that needs to be done.”

She claimed local councils were making development decisions at odds with the coastal science, “so we get problems like the Narrabeen-Collaroy sea wall”.

Why is the Narrabeen-Collaroy sea wall a problem?

The vertical concrete sea wall is seven metres high and 1.3km wide, and was built in front of private properties on Collaroy and Narrabeen beaches.

The Nature Conservation Council states: “Seawalls of this design have been shown – all over the world - to destroy beaches. Seawalls have the inevitable effect of reflecting and concentrating wave energy and accelerating erosion. Eventually, the beach narrows and disappears.”

Hanley described sea walls as the “worst possible solution”.

The Griffith University report for Surfrider forecasts less frequent but more intense storms, as well as a worsening of flooding events due to the sea level rise.

The local community has been protesting the sea wall since 2002. Among them is University of Sydney Professor Andrew Short, who Hanley described as a “world-leading researcher” on coastal and marine science.

“There will be no beaches left”: What is going to happen if there’s no change?

Hanley was angry about local councils supporting Development Applications that she said were not in the interests of coastal longevity, citing the restoration of Newport Surf Life Saving Club’s premises, which she said would “save the building and destroy the beach”.

“If we keep going the way we are, there won’t be a Northern Beaches anymore. It will be the Northern Walls. There will be no beaches left.”

There are currently no plans for additional seawalls on the Northern Beaches.

“We have the solutions”: What can be done?

Sustainable solutions to mitigate climate change effects in Narrabeen will be costly and require a shifting of community priorities.

Whether it’s sand nourishment (successfully implemented on the Gold Coast) or acquisition of properties along the shoreline to convert to public land that’s easier to manage, some of these solutions require local homeowners to give up their properties.

While the impacts of climate change are becoming more evident - warmer oceans, more intense storms, erosion, dirtier algae in swimming pools, beach closures due to stormwater run-off - Hanley said it was understandable that some in the community still turned a blind eye.

“It’s joining the dots that’s hard,” she said. “The most important thing for us is to have coastal experts at the helm.”

Politicians who are onside with taking localised climate action, according to Hanley, include Pittwater MP Jacqui Scruby, Mackellar’s Independent MP Sophie Scamps, and former state environment minister and now Manly MP James Griffin.

Surfrider’s CEO Steph Curley said the research findings show the Australian way of life is at risk.

Thumbnail image credit: North Narrabeen satellite image courtesy TomTom / Narrabeen-Collaroy sea wall image courtesy of Rowan Hanley