Castle Hill fire remains too difficult to contain

Fire crews say it is too dangerous to establish containment lines around a large fire burning in the Canterbury high country, so they are focusing on bringing it under control instead.

The blaze, which started on Thursday morning, has burned through nearly 1000 hectares at Bridge Hill, northwest of Springfield.

Incident Commander Colin Russell said on Saturday afternoon it was not safe to contain the fire on its perimetre due to rugged terrain and cliffs. Instead, he said crews were trying to control it by suppressing hotspots and flare-ups.

Some members of the public were reported on the fringes of the exclusion zone around the fire at Cave Stream and were removed from the area with the assistance of police.

Russell said more than 100 firefighters were battling the blaze on Saturday, as well as three diggers and four helicopters.

Strong winds and higher temperatures were earlier forecast for Saturday afternoon. Firefighters were battling to get the blaze under control in Saturday morning's more favourable weather conditions.

Russell earlier said while it was still not yet contained, it was remaining within its 17km boundary and not expected to grow in size.

Residents around Castle Hill were on standby to evacuate should the blaze spread.

The fire started early on Thursday morning, closing State Highway 73 and burning through more than 1000 hectares at Bridge Hill, northwest of Springfield.

The Holloway Lodge, near the peak of Bridge Hill, was destroyed.

Russell said 110 FENZ staff were still working to contain the blaze as the weather turned.

"This afternoon the wind is forecast to strengthen, and temperatures will be in the mid- to high-20s. This will be less favourable conditions for getting this fire contained and the risk of breakouts will be higher so we will be closely monitoring the fire."

All recreational areas between Castle Hill and Lake Pearson were closed to the public, FENZ said on social media.

"This is still an active fire zone and with the winds increasing the risk of a breakout fire is higher. Please do not move cones and signs that are blocking off these areas. When you do this it ties up valuable resources trying to sort evacuations, when we should be working on the fire ground."

Seven FENZ crews had monitored the site overnight.

Fire retardant lines had been placed around at-risk properties and crews would be focusing on the ground.

There had been five helicopters helping to battle the blaze, and FENZ was expected to do an aerial reconnaissance flight on Saturday morning to assess any damage and the extent of the fire's spread.

SH73 had reopened, but stop/go signs were in place and traffic was being taken through the affected area in piloted convoys.

"We'd like to thank all the road users for their patience and adhering to the traffic restrictions in place," Russell said. "It has meant we can keep the road open in a safe manner so people can continue to pass through."

Strong wind warnings were in place for much of the South Island from early on Sunday, with northwesterly gusts picking up on the east coast through Saturday.

Another fire breaks out in region

Meanwhile FENZ shift manager Simon Lyford said crews were fighting another scrub fire in North Canterbury, just south of Culverden.

Crews from three stations were trying to get on top of the fire, but the wind was not helping, he said.

"We do have a helicopter on standby ready to respond, but at this stage the crews are saying that they believe that they will be okay."

It was more than 90 kilometres away from the Bridge Hill blaze, he said.

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