Groynes proposal on agenda

A campaign to return groynes to Dunedin’s Ocean Beach could take another leap forward today.

Dunedin city councillor Jules Radich, who pushed the project during the council election campaign, wants a staff report on options to reinstate the timber groyne at St Clair.

That report would include an assessment of risks and benefits of the groyne, including reference to Kettle Park and the risk of doing nothing, a construction time and cost estimate, and an assessment on the effects on the wider coastal system and council work programme.

He has proposed a motion asking for the report to be discussed at today’s full council meeting.

Dunedin city councillor Jules Radich is keen to advance his plan to reinstate groynes at St Clair...
Dunedin city councillor Jules Radich is keen to advance his plan to reinstate groynes at St Clair. PHOTO: PETER MCINTOSH

Council staff have previously said reinstating the groynes to build up sand along the beach would be considered, but only as part of long-term planning for the area.

Other possible options canvassed have ranged from construction of a new sea wall or rock groynes, to the removal of the old landfill and allowing a natural dune system to return.

Mr Radich said he had been discussing the issue with both staff and fellow councillors, and there were a range of views on the groyne proposal.

"There is enthusiasm in some quarters, and a lack of enthusiasm in others."

daisy.hudson@odt.co.nz

Comments

View all

Sea level rise and the power of surges will soon sweep away any concrete and groynes. One large swell can lift and move any man made structure like matchsticks.

Maybe Jim, but its certainly ironic then that no swells over the last 100 years have knocked over the existing timber piles/groynes.
I have always said the groynes are a cheap band aid that is worth trying. Even if they only last 50 years just place another set then. It would certainly be worth investigating sending the digger and auger with some marine piles down for a few days, given the escalating costs of dumping/filling sand bags and placing boulders over the bank like they have for the past 5 years.
Build the match stick wall and watch it works its wonders.

With sea level rise the water will get over, under or around any man made barrier. Building 1000's km of concrete around NZ won't work. Timber piles won't stop 10 meter swells either.

Yes, you are correct, with sea level rise all sorts of things are going to happen, but we can't just put heads in the sand. However, what is needed is some sort of medium to long term solution. How are other parts of NZ and other countries affected by sea level rise coping? What systems do they have in place or planning to build? Are any of their problems similar to ours, and if so, how can that be adapted to our conditions here? Looking at similar economies of scale, what can we afford? Surely DCC planners and enviromental experts will do some extensive research. Maybe a simple solution is the best, even if it's the timber piles or even better, the concrete breakwater in New Plymouth. They are somewhat triangulated, allowing them to lock together and resist rolling movement. They cope with massive west coast sea conditions, and appear to do very well.

Supposed sea level rise, until it actually happens it is pure conjecture.

Just a footnote. Have discovered the concrete blocks used on New Plymouth harbour breakwater are called 'AKMONS'. I have seen for myself how effective the Akmons are in rough weather. They literally diffuse wave power and pressure almost immediately.

View all

 

Advertisement