Meet the real rock stars
Vicki Anderson goes hiking with the people blowing stuff up in the name of safety around Christchurch’s Port Hills.
Tension is in the air as the explosives are eased into place. The rock stars are ready to roll. The only noise on Christchurch’s Port Hills on an unseasonably warm Wednesday is courtesy of the bird choir fluttering delicately between tree branches.
Having gingerly traversed a narrow track of spiky gorse bushes, I turn to survey the spectacular view across the city.
To the left is the Airways Cass Peak radar and communication site which looks a little like a massive soccer ball perched atop an icecream cone. I cling to the wire fence of its perimeter to snap a photo as beside me is a sheer drop to a gully.
Several hundred metres below, a man in an orange helmet is scaling a cliff face like an agile mountain goat. Minutes before I’d observed him perched there, like a pimple on an elephant’s bottom, eating his lunch in mid-air.
That man is Martin Freeman of Christchurch-based contracting company, Solutions 2 Access, with specialist skills in construction, abseiling and rockfall control. Freeman arrived at work armed with explosives and a strong desire to blow stuff up, explains Scott Barnard, an engineering geologist with global firm Aecom, which has an office in Addington and was last year named by Fortune magazine as one of the World’s Most Admired Companies.
For more than five years, an unlikely alliance has formed between the Aecom team, Christchurch City Council’s park rangers and explosives experts like Freeman as together they’ve sought to clear the many walkways around the Port Hills of any rockfall dangers.
Or, as they call it, ‘‘popping’’ nature’s pimples.
Cantabrians now have a heightened awareness of rockfall risk but misconceptions still abound.
‘‘There is often a perception that the earthquakes have removed all the loose rock so it must be fine now,’’ says Barnard. ‘‘In actual fact loose rock was indeed moved by the earthquakes, but much more rock was damaged and destabilised, leaving a lot of quite precarious material on the hills. We still see it coming down in areas we haven’t yet treated.’’
Barnard has helped make many post-earthquake sites around Canterbury’s safe from rockfall.
‘‘Many are treated specifically for parks and many are for roads, houses, lifelines – or a combination of at-risk structures and areas. Also, some sites consist of a single boulder, others may be a group of boulders, or it could be an outcrop or bluff with multiple boulders. We have mapped fallen boulders and in-situ unstable rock. Not all of the fallen boulders pose a risk and require treatment, others have.’’
The boulder he has in his sights at Cass Peak on the day we visit is not the biggest obstacle he’s helped clear but he views each one blasted to oblivion as a potential life saved.
Today he’s working as a ‘‘spotter’’ for Freeman’s team. This involves making sure that the blast site is clear of any lycra-clad runners and assorted ramblers.
Passing me a hard hat, he disappears up a trail to place a danger sign across a track in preparation for the countdown.
At first glance the hillside seems deserted on a midday lunchtime but I count seven people in the space of just a few minutes.
Two sweaty joggers in Nike singlets have been steered my way by Barnard.
‘‘We’re waiting for the big bang,’’ puffs one of the men as he passes, running uphill.
A woman wearing a bright orange fluoro vest zips past me towards the blast area. I wave my arms and call out to her but she
has her headphones in and doesn’t notice. Minutes later she is zigzagging back down the track towards me, having been diverted by Barnard.
Then all is still and I am alone on a hilltop wearing a hard hat.
By the boulder below I can see Freeman’s speck of an orange hard hat darting about.
It’s like being in the middle of a Roadrunner cartoon, waiting for the Acme explosives to detonate. THE BEST VIEWIN TOWN
Earlier, I’d joined Barnard as he visited the Victoria Park HQ of Paul Devlin, the Christchurch City Council’s Port Hills Area head ranger.
Put simply, the man has the best view in town.
This year more than 1.2 million people have visited the Port Hills and the number is rising.
To some the words ‘‘park ranger’’ might conjure up images of Yogi Bear and picnic baskets or an episode of Parks and Recreation but Devlin laughs at the notion as he pulls up a chair across from Barnard at a table covered with a giant map of Canterbury.
Devlin’s particularly happy about the Cass Peak explosion.
It’s a comparatively small job but it’s a significant moment.
‘‘That’s the last piece of work, the last segment of the Crater Rim walkway,’’ Devlin says. ‘‘It’s a bit of a big deal for us to finally get the Crater Rim network open.’’
He recalls sitting in his office after the 2011 earthquake wondering where to start.
‘‘It was after our team stopped doing the immediate recovery work in town, pretty unpleasant work. We regrouped up here and drew big circles – green, red and orange for risk – around our parks as a guess of what we could do. We were bang on. We thought ‘how are we ever going to get back there?’ but we have.’’
‘‘It’s a bit of a big deal for us to finally get the Crater Rim network open.’’
He cites good funding as the main reason the project has run smoothly.
‘‘It was recognised that the Port Hills were a popular recreation area and that getting out into the outdoors is an important part of the recovery process physically, mentally and spiritually.’’
There are still some park areas that aren’t accessible to the public and Devlin says that ‘‘at this stage’’ such sites will remain closed.
‘‘It’s a horrible term but we look at ‘cost benefit’ and in other cases it’s technically not feasible.’’
Mountain bikers are anticipating the Adventure Park but in the Port Hills the rock climbing fraternity have been the ‘‘biggest losers’’, Devlin says.
‘‘It was a climbing mecca pre-earthquakes, there were well over 1000 routes on the Port Hills for them, now there are just a few.’’
Some threatened plant species and lizards have also fared badly. Protected geckos were moved to Riccarton Bush in March.
‘‘Ironically some of the threatened plant species… their favoured habitat is on the rocky bluffs,’’ Devlin says. ‘‘The lizards have also suffered badly.’’
Barnard smiles and says: ‘‘Ah, the lizards’’, to himself in a somewhat resigned fashion.
Devlin notes that Barnard and his colleagues have become experts in wildlife recovery and that his park rangers have become ‘‘pretty good geotechs’’.
‘‘All you guys do is the wriggle test,’’ Devlin jokes to Barnard. ‘‘You push the rocks with your hands to pop them or give them a big of gentle persuasion with a crowbar.’’
But then his face becomes more serious: ‘‘We regard Scott like a ranger.’’
Their unlikely partnership has offered many surprising benefits.
‘‘It’s obviously not the best circumstances,’’ Devlin says. ‘‘But we’ve learnt a lot from each other and, for our part, working with these guys… our eye for risk in the landscape has greatly improved.’’
In the beginning, both agree, it became a question of ‘where do you stop?’
‘‘The benign old Port Hills aren’t benign. In the early days post earthquake huge amounts of the landscape got completely denuded of all rocks, then we got the handle on that and the models changed.’’
There is now more signage on the tracks, something Devlin doesn’t like aesthetically but which he knows is vital.
Fondly Barnard recalls the massive amount of work involved with clearing the bluffs above Summit Rd by the Gondola.
‘‘Now that was an explosion,’’ he says emphatically.
‘‘We removed 6000m3 of rock to reduce the risk to the Summit Rd below and that is effectively a parks area now that it is closed to vehicles.’’
Devlin admits he is ‘‘quite enjoying’’ the closed Summit Rd.
‘‘From Rapaki through to Mount Cavendish it’s open to just cyclists and pedestrians and people are loving being able to use the road as a trail. The weeds are recolonising the roads.’’
The Port Hills track network has attracted more than 1.2 million visitors this year.
‘‘That’s not vehicles, that’s people,’’ Devlin says. ‘‘It has only increased since the earthquakes.’’
To encourage people to be more aware of the risks, the parks team have rerouted tracks, installed signs and removed seats at certain points so people aren’t encouraged to stop and sit there.
‘‘There’s a heightened awareness now from the Canterbury public,’’ Barnard says. ‘‘After the Valentine’s Day earthquake trigger event, for example, it was gratifying that all of the areas we had treated were fine.’’
BYE, BYE BOULDER
Through Barnard’s walkietalkie someone is counting down from 10. The air is still. Even the bird choir is silent. Bang! Bye, bye boulder. The rock has been blasted to smithereens and, pleasingly, these smithereens have landed more or less where Freeman and his crew expected them to.
Later, after my hard hat is returned to Freeman – a man with a broad smile who clearly enjoys running around the hills blowing stuff up – Barnard and I stop to survey the hills from a vantage point beside a giant boulder on which someone has painted an incongruous pink smiley face.
He gazes and points to far off dots on the landscape that he knows like his own face and recalls boulders he has previously helped ‘pop’.
Prior to the earthquakes, the Cantabrian enjoyed an occasional visit to the Port Hills but now it is clear he has a real passion for the area, rattling off the names of remote outcrops with affection.
Before the earthquakes he’d never been abseiling. Now he abseils regularly in the course of his working day.
In the past five years he’s worked on around 500 sites.
‘‘These are sites with unstable rock above tracks that we have treated and removed, excluding sites remediated for other reasons that may have also benefited parks. Some of these sites will have multiple rocks, so well over 1000 rocks all up.’’
The geotechs and the park rangers have walked almost every inch of the Port Hills and now both have a greater understanding of the land beneath their feet.
‘‘The rock factor is now a part of our everyday life,’’ Devlin says. ‘‘It’s only been since the earthquakes, but it’ll be an ongoing thing now.
‘‘Nature does a great job of looking after itself, we’re just helping it along.’’