Flare-ups from old fires pose a ‘major threat’
Hot, windy weather in the region means fires thought to be long extinguished could flare up again, prompting warnings to recheck ash heaps.
The rising fire risk has also forced the closure of reserves such as the Grampians Reserve behind Nelson and mountainbiking areas, including Sharlands, Kaka Hill and the Fringed Hill Road.
The Nelson City Council said the risk in the reserve was if a fire broke out people could easily become trapped.
Principal rural fire officer Ian Reade said fires that flared up again, often weeks later, were called carry-over fires. Because of the weather they were ‘‘a major threat right now’’.
‘‘If we can ask people, if they’ve had a fire in the past two months, go and check it, rake it out and water it down,’’ he said.
A shed on a Little Sydney Valley property, near Motueka, was destroyed on Wednesday by a fire that had reignited from a week-old burn-off.
Firefighters said embers buried under the ashes, combined with dry conditions and high wind, created an ‘‘oven’’, which reignited the fire.
Reade said rural fire services in Tasman were fielding daily calls about carry-over fires sparked from ash heaps which were still smouldering, despite appearing to be extinguished.
These fires typically started when old fires developed a hard crust on the ash heap, protecting deeper hot-spots or embers, he said.
‘‘The wind can get amongst that and fan it, and it’ll spread [the fire] to the dry grass around it. It’s not uncommon at all.’’
Reade said people need to ‘‘make a conscious effort’’ to extinguish all fires, especially larger ones or ones which left partly-burnt logs or stumps, which can smoulder for a long time.
All fire permits north of Korere Valley, south-west of Nelson city, were cancelled last Friday.
‘‘It’s very, very dry; for reference, it’s drier than it was for the Port Hills fire [in Christchurch] earlier this year, so that gives some idea of what could happen,’’ Reade said.
If a fire did start, there was a real chance firefighters would not be able to contain, he said.
‘‘If one starts with a little bit of wind behind it, it’s likely that we won’t be able to contain it.
‘‘Once you get over a certain intensity no matter how many helicopters you’ve got, or people on the ground, you can’t stop the fire until it gives you a chance.’’
No beach fire permits will be issued in the region for the Christmas and New Year period.
Tasman Pine Forests have closed all forests to non-essential access.
Kingsland Forest in Richmond, Tunnicliff Forest near Wakefield and internal Rabbit Island tracks have also been closed.