Mountain safety experts are urging snow revellers to play it safe when searching for back-country powder.
Recent snow storms at Southern Lakes skifields have created a huge avalanche risk on the slopes since many mountains have no snow base in the first place.
The Mountain Safety Council’s avalanche programme manager Andrew Hobman says the massive dumps have been a “one-in-ten-year event” and the sheer volume on wet tussock means dangerous snow layers have formed and it’s difficult for snow to settle.
“It’s very peculiar that we’ve gone from absolutely nothing to this sort of storm.
“Also significant is the fact there’s been so much wind with the storm – a lot of the snow was blown off the ridges and ended up in the mid to lower mountain.”
This means skifields have had to use more explosives than usual for controlled avalanche bombing.
Wanaka’s Treble Cone has even had to commission a helicopter to bomb in areas usually unaffected, like the ridges above the access road, spokesman Nigel Kerr says.
“I don’t know how much explosive we’ve used – I’m not sure it’s an absolute record, but it’s just been continual and we’re hoping that it will warm up and bond the snow together a little bit,” Kerr says.
Last week the avalanche risk was “high” for Queens-town mountains between 1000 and 2000 metres and Wanaka mountains between 1000m to above 2000m, according to the Mountain Safety Council’s website. This week it’s been downgraded to “considerable” for Wanaka slopes and “moderate” in Queenstown.
It’s almost two years since Queenstown man Ryan Campbell, 30, died while snowboarding beyond the Coronet Peak ski area boundary. Campbell was riding with his brother when an avalanche was triggered – burying him under 3.5m of snow.
Hobman says it’s essential for back-country skiers and snowboarders to be aware of the risks, adding it’s best to stay off black runs and stick to low-angle terrain in present conditions.
“The critical slope angle to trigger an avalanche is 35 degrees, which is also the perfect angle for skiing.
“Ninety per cent of people who are caught in avalanches have triggered the avalanche themselves. You can avoid that by avoiding the terrain that can happen on.
“Plan your trip and be aware. Ask people, make good decisions. Find out what the conditions are and where they are,” Hobman says.