Narrowneck artificial reef nears completion (updated)
Back in 1999, surfers on the northern Gold Coast were rejoicing following news that an artificial reef would be built at Narrowneck. The northern Gold Coast has a history of erosion yet it was partly halted in 1985 with the construction of the training walls at the Spit - a project that unwittingly created one of the Gold Coast’s best beachbreaks at South Straddie.
The walls, however, had no effect further south at Narrowneck, and in 1990 Cyclone Nancy eroded the beach back to the boulder reinforcing wall that separates the ocean from the Nerang River. In response to this and other erosion events the Gold Coast City Council investigated building an artificial reef to slow erosion, and in a bout of value adding they called it an MPR - a Multi Purpose Reef, the ‘multi’ referring to its potential surfing amenity. If the new reef could create a wave then more the better from a PR point of view, especially at a surf-centric region like the Goldy.
Narrowneck artificial reef from the air
New Zealand coastal engineering firm ASR were contracted to make what was then the world’s first Multi Purpose Reef, and the north end surfing community were promised great waves from the project. The reality, however, fell well short.
In a last-minute bout of cold feet, the council lowered the depth of the reef a metre prior to construction. The change would have no effect on sand accretion but was terminal to Narrowneck becoming a good surfing reef. A 2007 report on the reef noted that “larger swells, lower tides, and offshore winds have the potential to produce hollow, plunging breakers”. The immediate question is: where doesn't under those conditions? The reports conclusion stated that due to the depth “the reef needs long period, clean swell to replicate the modeling.”
In the intervening 17 years Narrowneck has only got deeper, the geotextile bags settling further into the sand. This year as part of a broader beach renewal program, the Gold Coast City Council began restoring the artificial reef at Narrowneck. Beginning in August they used a split hull boat to dump new sand-filled geotextile bags into position. As of late October, 33 new bags have been dumped and the work will continue until December.
(Update 08/11/17: the operator of the boat claims the reef won't be ready in four weeks, but "more like three months".)
The split hull dredger 'Faucon' at the reef site
The council is aware the last reef fell short of surfing expectations and have asserted that surfing amenity will again be considered. But to what extent remains unknown. A scaled wavepool was built to imitate the breaking waves, though Swellnet wasn’t able to see video of it. The council could, however, confirm that data from the physical modelling informed their decision to alter the shape of the reef. Further optimism comes with news the reef height will be elevated.
“The renewal project will place geotextile containers on top of the existing reef footprint,” said a media spokesperson at Gold Coast City Council. “This will raise the crest - or surface - of the reef.” Again, to what extent remains unknown, yet the hope is that this time it replicates the modelling.
(Update 08/11/17: the operator of Faucon says the new reef will be "a lot shallower". Currently, some of the depths at low tide on the reef are 2.5m to 2.6m and a second layer of bags is yet to be laid on top of that. The bags are approx 2m high so as the skipper says, "it will be shallow for sure".)
Swinging between optimism and skepticism, Swellnet spent an hour watching the partially constructed reef last Sunday. Under three feet of clean south-east swell, a negative tide, and light winds a few sets were capping above the construction zone though the reef itself was unsurfable. There’s still more than four weeks till the job is done and, weather permitting, the Faucon will be dropping between one and three bags each day.
For now though, keep your expectations in check and stay tuned - or simply check on progress yourself.