Carrickalinga residents want wave generator that sank off SA coast to be blown up

This wave generator sank off the SA coast five years ago while being towed from Port Adelaide — and it’s just stayed there. Now, frustrated residents want it to be demolished with explosives.

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Carrickalinga residents want the State Government to consider blowing up a wave generator which has been sunk off the coast for five years, after plans to remove it faltered.

The wave generator, owned by defunct company Oceanlinx, sunk in waters off Carrickalinga in March 2014 while being towed from Port Adelaide to Port Macdonnell, creating an eyesore for residents and holiday-makers.

After going out to tender for its partial removal last year, the government’s plans to remove it are back to square one, infuriating local residents.

The Advertiser reported in September that after years of consultation, and ideas such as blowing the structure up being mooted for its removal, that it would be cut back to 1m below the low-tide level, with the rest of the structure staying put to form an artificial reef.

Locals weren’t impressed, with Bill Chapman, treasurer of the Carrickalinga Ratepayers’ Association, saying the State Government had taken the easy option.

The wave generator sunk off Carrickalinga. Picture: Dylan Coker

The Oceanlinx wave generator, sunk about 1 km off Carrickalinga. Picture: Dylan Coker

Now, unhappy with the bids received for the tender to cut the top off of the structure, the Department of Planning, Transport and Infrastructure has put it out to tender again, with bids closing on April 30.

In a letter to Minister for Transport and Infrastructure Stephan Knoll, the Ratepayers Association says it wants the structure destroyed, with explosives if necessary.

Four options are being considered as part of the new tender:

PARTIAL removal to land and dispose

PARTIAL removal and re-sink adjacent to existing structure

TOTAL removal to land and dispose

RE-FLOAT and re-sink in deeper waters

In letters to the Minister, Mr Chapman says the structure is a navigational risk, and warns the State Government would likely be liable should any vessels hit it.

Mr Chapman suggests concerns around an activist backlash have prompted the government to shy away from blowing the structure up.

“DEMOLITION was not on the list … why?’’ Mr Chapman writes.

The Oceanlinx wave generator is towed out from TechPort, to be

“Was it because once demolition was considered, environmental arguments would be raised and this puts this problem into the ‘too hard’ basket, so to reduce the ‘flak’ from the conservative lobby it was decided to go with the cheapest option aimed at minimising the visual impact of the structure while minimising any backlash from the environmentalists?’’ he writes.

“In our opinion the best way to deal with the problem is for the structure to be demolished, so allowing the concrete fragments to settle on the sea bed forming an artificial reef, at a height from the seabed which would be safe.

“At the first public meeting held in the Yankalilla district addressing this matter, a member of the public, who happened to run a demolition company, informed those present that demolition of the wave generator would be straight forward, not be expensive and could be done in such a way, (using small impact-controlled explosions) that it would have minimal effect on marine life.

“If demolition is considered, both the Navy and the Army may be interested in using the site as a marine demolition exercise, as they have done in other parts of Australia in the past.

Or a private demolition business could be used.’’

Locals Chris Hughes, Rosemary Mather, Chris Mather, Bill Chapman, and John Lawrence are not happy the situation still hasn’t been resolved. Picture: Dylan Coker

In a letter to the Association in February DPTI did not address the demolition issue, but did say “any other alternative disposal methods” would be considered. The new tender does not mention or specifically exclude the use of explosives.

A statement from DPTI today said: “A contract was not awarded for the partial removal of the structure as DPTI did not consider that any of the tenders received were value for money.

“DPTI has recalled the contract, offering more flexibility to tenderers in an effort to identify a solution and price that represents better value for money.

“Once tenders are received, DPTI will consider what option delivers best value considering environmental factors, navigation safety, visual amenity and cost.

“Because of the variables in the process, it is difficult to accurately estimate the likely cost or timing of the work.”

The concrete and steel wave generator sits in 16m of water and has a blinking red beacon attached to it to warn boat users of its presence.

It also has a 100m exclusion zone around it because of dangers associated with currents it could generate.

The 3000-tonne Oceanlinx wave generator — intended to generate power by harnessing the power of waves — was being towed to Port MacDonnell in 2014 when it sank to the sea floor, where it has remained ever since.

With Oceanlinx now in administration, it fell to the State Government to look at clean-up options.

The project was valued at $7 million at the time and received a $4 million Federal Government grant, but following the sinking the company running the project, Oceanlinx, collapsed.

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