NZ King Salmon Farm returns safe and sound

Wednesday 7 June 2006

NZ King Salmon Farm returns safe and sound

The NZ King Salmon Co Limited announced today the successful return of its Te Pangu farm to its Tory Channel site following the mooring slippage in early March.

The past three months have involved firstly an audit of fish losses and damage, an investigation into likely cause, acquiring the best expert mooring advice possible for the farms return, repairing the cage infrastructure and attendant grow-out nets and then preparing the optimal and reliable mooring array for the farms return.

The return of the farm was also timed to coincide with supportive tides.

Damage and fish losses were largely covered by insurance; however the major loss was in very small fish, only 3 months in the seawater and their escape results in an opportunity loss next autumn when they would have reached harvest size. Some anecdotal reports suggest that some lucky fisherman have been able to benefit from the loss of the young fish. However it is likely that most would not have survived the lack of feed and natural predators in the Sounds area. Fortunately the company has been able to mitigate the fish loss with additional smolt stocks though the timing of their grow-out is slightly later.

The investigation into the cause has involved previous mooring consultants to the Company, additional independent experts and insurance assessors. Their conclusions have not found a simple single cause. Rather the likelihood that a range of factors contributed to excessive pressure on one section of moorings. The extensive array of 31 moorings, both block and screw anchors, did not evenly spread the load and this resulted in the failure of some initial mooring lines. This then allowed the farm to skew across the prevailing current, increasing the mooring load with a cantilever effect resulting in a cascade of mooring line breakages.

In looking to ensure this event will not happen again, the company has insisted on increased redundancy in the mooring system, has implemented the latest expert advice towards a single array of screw anchors only (some 34) and most importantly added in a tensioning management plan utilising chain connections designed to ensure that mooring loads are always evenly distributed to prevent a repeat of the cascade effect that occurred in March.

The screw anchors were installed in May and tested for load factors. Meanwhile a range of the 34 mooring lines, a cumulative total of 9.3 kilometres of rope were individually checked and tested for tension to a specific level of force.

“We have confidence in the expert advice received that the farm can be safely moored at its site secure against even the extreme forces that can be expected” commented Stewart Hawthorn the Company’s Aquaculture General Manager.

“We commend and thank the contractors, experts and our staff for the huge effort that was made in securing the farm on the day of the incident in a safe and as non-disruptive a manner as possible, similarly for its protected return today” said Mr Hawthorn. “Equally we are grateful for the widespread support and encouragement we have received from the community. While supplies to our consumers have not been affected it is good to know our farm is back on site, safe and sound” concluded Mr Hawthorn.

ENDS

© Scoop Media