17 hours ago
Erosion on Gold Coast beaches could take three years to recover from Cyclone Alfred
By
Nicholas McElroy,
ABC
Exposed rock walls near Narrowneck on the Gold Coast three months after Cyclone Alfred.
Photo:
ABC News: Nicholas McElroy
It is the last line of defence for properties on the Gold Coast - and high tides keep crashing against it.
Three months after Cyclone Alfred hit the the coast, parts of the city's "A-Line" rock wall remain exposed.
Beach walkers and residents on the northern Gold Coast say they cannot see it being fixed in a hurry.
"It's just ruined the beaches, the high tide comes right up to the wall," said Main Beach resident Rod Clutton.
Damage at Narrowneck Beach on the Gold Coast three months after the cyclone.
Photo:
ABC News: Nicholas McElroy
More than $30 million has been spent on a sand-pumping barge so far, but successive swells and high tides have hurt recovery efforts.
"I just don't know how it's going to be fixed," Clutton said.
The Gold Coast's beaches could take up to three years to fully recover from the storm, according to the council.
It said Cyclone Alfred was the worst weather event to hit the city in 50 years, and beaches were the narrowest they had been in 25 years.
Although it might look bad, the beaches have eroded many times before.
Cyclone Alfred ripped an estimated 6 million cubic metres - or 2000 Olympic swimming pools - of sand from beaches across the city.
A bulldozer shifting sand on Surfers Paradise Beach at low tide.
Photo:
ABC News: Nicholas Mc Elroy
But coastal engineer Angus Jackson said the sand should not be thought of as "lost".
"We know from 60 years of survey data that sand is gradually moving onshore, so nothing is lost," said Jackson, chief executive engineer at International Coastal Management.
"It's just constantly translating offshore [and] onshore."
The beaches are still vulnerable to future storm events.
While there are plenty of spots to pop down a towel on the city's 52 kilometres of beaches, the worst visible impacts are north of Surfers Paradise.
That includes Narrowneck Beach, which gets its name from the narrow strip of land separating the Nerang River from the Pacific Ocean.
"We've got to protect all our beaches, especially our vulnerable points," Tate said.
"Because if Mother Nature comes with another [Cyclone] Oswald to Narrowneck right now, it could potentially break through."
The council said it planned to move more than 1 million cubic metres of sand to beaches over the next year.
Tate said he would "work to find a long-term solution to make sure Narrowneck would be safe for the future".
Dredge works have been ongoing after the storm.
Photo:
ABC Gold Coast: Steve Keen
He pointed to existing artificial reefs at Narrowneck and Palm Beach, which were built to protect the coastline from extreme weather events.
Breakwalls, rock groynes and a network of pipes and sand stockpiles are used to nourish the beaches on the Gold Coast.
There have been a number of proposals to protect Surfers Paradise beach over the years.
Jackson said a fringing reef built offshore could be a solution to protect the coastline.
He said it would minimise the impacts on the beaches by softening the blows of a large storm swell.
"[The water offshore] would look like it looks now unless we get a storm with over 5-metre waves," Jackson said.
"Suddenly you'd see the waves breaking out towards the horizon and the energy not reaching those upper beaches.
"Day to day, you wouldn't know it was there," he said.
The beach separates a lot of real estate from the ocean.
Photo:
ABC Gold Coast: Dominic Cansdale
Jackson, whose company has won Gold Coast contracts, said a project could build on lessons learnt from artificial reefs at Narrowneck and Palm Beach.
"We can have this hidden protection that's below water level," he said.
"With sea-level rise, you gradually increase the height of the reef."
At the end of the day, Jackson said it was important to get sand back onto the shore to soften the blow of any future storms.
"What we need is a enough buffer zone so when we get that storm hit, instead of it [surf] being in the middle of the Esplanade, it's back [on the sand] and we still have a usable beach," Jackson said.
He said council's recovery timeline seemed conservative, and sand would soon be pushed toward the exposed rock walls.
"That's the first time we've seen that [Narrowneck] boulder wall in 26 years. It'll recover again - the sand backpassing will bring sand back," he said.
"We've made the beaches much more resilient, they're not natural anymore, they're very much managed."
- ABC
