Waihopai Valley residents, whose homes are in danger from an out of control forest fire, have been told if the call to evacuate is made they must respond immediately.
About 80 people attended a meeting today due to the fire which has consumed more than 1200 hectares of pine forest and farm grassland since Thursday, moving from the Wairau Valley towards the adjacent Waihopai Valley.
Marlborough Principal Rural Fire Officer Richard McNamara said it was three times the size of the last large forest fire in Marlborough a fortnight ago.
Thirteen aircraft are again being deployed today; the maximum number that can safely be used inside the fire zone.
The firefighting costs are about $400,000 a day.
Mr McNamara said residents had been encouraged to take their own fire safety measures, including clearing access to their properties for fire appliances; removing any fuel close to their home and clearing gutterings of leaf litter that could ignite with flying sparks.
He said he gave a reassurance that fire crews were doing their utmost to hold the fire back from the valley but, if the winds turned and the risk was judged too great to stay, an evacuation order would be made.
Mr McNamara said crews were dealing with a monster fire, and it was generating so much heat that half the water being dumped on it was just evaporating.
He said while the aerial attack resumed at daybreak with 4 millimetres of rain falling overnight, this morning had given crews their the first real opportunity to get stuck in on the ground.
The blaze started on Thursday afternoon in a commercial pine plantation belonging to Nelson Forests, a few kilometres to the south of Wairau Valley township.
It is now the largest blaze in the region since the Boxing Day fires of 2001.
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The fire was still burning out of control on Friday afternoon and had burnt through 1150 hectares of forestry and farmland with the perimeter of about 18km, Mr McNamara said.
Ember showers from the fire have spread it over an area of more than 1100 hectares.
All forest harvesting operations in the region were now suspended or totally limited.
The industry triggered a code red status this morning, the Marlborough Forest Industry Association's executive officer Vern Harris said.
"The Fire Authority issues what it feels is the correct code and the various forest owners would generally abide by it, or perhaps they might like to try and mitigate against it," he said.
Mr Harris said that included having helicopters on standby, but the economics of such measures determined whether operations continued or stopped.
'Long battle' to control Marlborough fire
Fire crews in Marlborough will face many days' work to control the forest fire.
Up to 800 hectares of pine trees have been destroyed and people have moved out of at least two isolated homes in the area, southwest of Blenheim.
Mr McNamara said that 14 aircraft and about 60 firefighters resumed working at the scene at about 6am and would take many days to bring the blaze under control.
"We may get some containment around it by the end of today, particularly in the higher priority areas, where it could conceivably start threatening the remote properties up in the Waihopai, but this is going to be a long battle. "
The fire is the second major blaze this month in the region, which is suffering extremely dry conditions. About 450ha of pine forest in the Waikakaho Valley was destroyed last week in a fire which began during commercial logging operations.
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"Like last week, it's just taking one day at a time," said Mr McNamara.
He said crews were focusing on trying to control parts of the outer edges of the fire.
Rural fire teams and forestry crews from outside the area have joined the effort against the fire.
The head of the rural fire authority in neighbouring Waimea, Ian Reade, said drier than usual conditions have had foresters in Marlborough and Nelson on edge since October, but El Nino strength westerlies have been the game-changer.
Mr Reade said when the risk is extreme, forestry operations are often suspended.
To share pictures or video of the fire with us, please email to: iwitness@radionz.co.nz