My mate, Hamish, tells a story of climbing with Bridwell (only Zoomers will need to ask AI who Bridwell was) on the big walls of Squamish in British Columbia, Canada. Night was falling and the pair needed to rappel (abseil) off the mountain. Bridwell slung an old stump left somewhere on a ledge (an un-anchored stump) and asked Hamish to sit on the stump while he (Bridwell) rappelled down. The stump wobbled but held, and Bridwell called up “off rappel.” Hamish, of course, now had to follow Bridwell down the ropes but without anyone to sit on the stump to hold it in place. Breathing out to lighten his stocky frame, down Hamish went. The anchor held, and the two were set to climb another day.
Years ago Doug and I climbed a little peak called The Tooth in the Cascade Range near Snoqualmie Pass in Washington. The south face is a very pleasant outing with climbing to Ewbank Grade 10 (about 5.4) which we climbed in a couple of roped pitches separated by some easy scrambling. We found ample fixed rappel stations to descend to Pineapple Pass where we decided to rappel straight down to the talus basin below instead of the longer more rambly approach route we had taken around the back of a big rock tower which makes up one side of Pineapple Pass. With a 60 metre rope, we had to stretch the rope right to the 30 metre mark to find a decent rappel station for the last rappel and were shocked to find at around 25 metres, some manky tat around a shrub obviously used by some desperate party to abseil off. This was a shrub; not a bush, not a small tree, merely twigs of a shrub the size of a small blueberry bush lashed together with a bit of webbing. Desperate and dangerous.
If you do anything long enough, even if you try to minimise risk, you have, if not an accident, at least an incident. Doug has rappelled off the end of his rope while cleaning climbing routes in Canada, and I have come exceptionally close in Australia (with rope stretch I just reached the ground and when unweighted the rope ended a metre or so above the ground). Once in City of Rocks, Idaho, while rappelling Cruel Shoes, we discovered that, contrary to what the guidebook indicated, our doubled 60 metre rope did not reach the anchor. This involved some jiggery pokery to get to the final rappel anchor including Doug down-climbing the 5.7 (grade 14) route! I’m embarrassed to say this is only a mere sampling of near accidents I have had while abseiling!
No-one should be doing any of these things. They are ridiculously dangerous if not outright foolish. But, among all my mountain incidents, I have never had an abseil anchor pull completely. While abseil accidents are regrettably common, most accidents occur when the sling fails, the gear pulls, or, infrequently terrain features such as horns, completely fail. Occasionally, people sling boulders which then roll right down the mountain. I remember one such incident from years ago in the Rocky Mountains of Alberta but, luckily the individual involved only fell a few metres because they were on terrain that most people would down-climb.
Bolt failures are relatively rare, but not unknown. In 2015, the UIAA (International Climbing and Mountaineering Foundation) published guidelines on stress corrosion cracking (SCC) of stainless steel bolts installed in climbing areas. Notably, Taiwan is one of the areas where SCC has been confirmed, but SCC most commonly occurs in areas close to the ocean and does not typically involve the entire bolt pulling out. Entire bolt pulls out is one of those low probability – high consequence events that people have trouble wrapping their heads around. The likelihood of the event is so low that it is very easy to get lured into a problematic situation where suddenly, it’s all good until it isn’t. The low probability-high consequence event is an absolute classic in avalanche incidents.
The Rescued Podcast (yes, there is the usual “but how did you feel” 20 minute introduction to get through) recently aired the story of three canyoners descending an “expedition” canyon in Taiwan. I can’t say I know what “expedition” canyoning is because people call a three day ski tour an “expedition” these days, but, apparently, the canyon the group were descending was infrequently traversed and required multiple days (or at least two; my mate Hamish would always say that a two pitch route is not multi-pitch) to complete. On the second day, the group approached an abseil down a waterfall that crossed a ledge and ended in a pool. A single bolt described as “an odd style expansion bolt” was found with a piece of cordellette tied around the bolt with the nut securing the cordellette on top. The protagonist describes this procedure as common in “expedition” canyoning to save weight. To a climber, this sounds, well, we can say the word again according to DJT, retarded. Your life is worth the weight of a hangar! And, if you put a maillon on the cordellette, you are close to the weight of an actual hangar!
Apparently the bolt that “wasn’t quite an expansion bolt” had a pin in the middle. This sounds like a hammer drive pin bolt designed for attaching materials like wood to concrete for “light to medium duty projects.” I’ve never actually seen one of these in the wild and I started climbing in the days of homemade hangars and button head bolts. But strange things do happen and bits of gear get used in inappropriate ways, like the two young blokes who “bolted” the Calgary Route (YDS 5.6 or Ewbank 13) on Mount Yamnuska, a decades old traditional route climbed by thousands of people without weird manky bolts and home-made dog-bones.
The first person down the abseil (the lightest individual in the group) inspected the surrounding rock around the bolt. It was described as “not spectacular.” The only attempt to test the bolt appears to have been a couple of jerks onto the anchor while the individual was standing on a ledge rigged to abseil. This, of course, is far less than even body weight plus backpack which is the absolute minimum an abseil anchor should hold. Abseil forces can reach up to 2 or even 2.5 kN (kilonewtons) even when the abseil is relatively controlled (not bouncing around like a lunatic).
from Lost Arrow Spire in Idaho
The individual went ahead and rigged her abseil, “grovelled down” attempting to only put a downward pull on the bolt not an outward pull, and reached the pool at the bottom safely. The next bloke down was a big fellow who probably outweighed the first abseiler by 30 kilograms. You know what happens next. That single anchor pulled and the second canyoner fell to the bottom breaking his pelvis. What follows is an extraordinary rescue and all involved are to be commended. But what of the lessons learnt?
Climbers and canyoners need to understand that it is really difficult if not impossible to determine the reliability of installed bolts by visual inspection. Unless the bolt is incredibly manky and pulls out with finger strength, you simply have no idea what condition the bolt is in. In this particular instance, the bolt used is wholly unfit for purpose and should never be trusted as a single anchor point in any event. As with most things in life, the edge case is easy to recognise but the middle ground where most of life’s events occur is opaque.
But, if you were absolutely desperate to use that single bolt, you could back it up with another piece of gear, or, if that is not available consider a temporary back up with a meat anchor and send the heaviest person first, the lightest person goes last. Still, this is incredibly dodgy because bolts have been known to fail on the second and third person down, and you must make sure that your meat anchor is only back up and does not take the load. If you get the rigging wrong you are not actually testing the anchor.
Guides talk about a concept called “error correction,” whereby errors are corrected as swiftly as possible. Sometimes, however, an error is so great that you simply cannot recover and all the things you did after the event mean very little, at least in terms of risk mitigation. Years ago, one of my friends set off to ski the south face (the sun drenched aspect in North America) of a big peak in the Purcell Mountains in early May. They left the trail-head at 11 am! If you are going to ski a south facing avalanche prone bowl in spring, you are at the summit above the ski descent by 9 am at the latest. It is very hard to correct for a catastrophic error of judgement. You might, as this party did, prevent further issues from arising, but sometimes the error is so extreme that the worst possible consequences have already arisen.
What about abseiling off single point anchors? Climbers, particularly in alpine environments do this all the time. It is with the caveat, however, that the single point anchor is absolutely bomber! And you must be 100% confident in your anchor because you are 100% dependent on it. If you can’t meet that exacting standard, do something else. Ironically, this team was carrying a bolt kit and put a bolt in after the accident.
It is amazing what people will do rappelling. And I’m not pointing fingers at the canyoning group because I have been on climbing trips where Doug has down-climbed entire 30 metre pitches just so we could avoid leaving a couple of chocks as an anchor. How stupid is that! In fact, I’ve probably made most of the mistakes pointed out in this article, notably, the ridiculous frugality that suddenly swamps the minds of otherwise sensible and cautious climbers who are probably going to blow more than the price of a couple of wires at the local bar that evening. Mind you, there are limits. Two of my friends once retreated off the south ridge of Mount Gimli in an advancing storm and left about a thousand bucks of gear on the climb!
There is a lot of talk about risk in the podcast. The injured canyoner believes that “risk is, is something that you have to, what you can calculate, of course [sic].” But this is not how risk works. Risk is the intersection between probability and consequence overlaid with exposure and vulnerability and while we might be able to estimate consequences relatively reliably, estimating probability is much less precise. The consequence of falling to the bottom of a pitch is likely catastrophic but how do we estimate the likelihood (probability) of a bolt of unknown origin pulling? Is it 10%, 20%, 90%, and even if the likelihood was only 1% would you do it if the consequence was a broken pelvis in a remote location? But it’s really exposure and vulnerability which cause the problem. Had the party backed up the anchor, or used a different anchor, they would have had no exposure and no vulnerability. Simply put, there would be no accident, no injury, no complex rescue. When it is hard to assess probability sometimes the safest solution is simply to avoid exposure. This is succinctly summed up in the adage commonly used in the ski-guiding community: if the question is stability, the answer is terrain.
Another member of the party when asked about risk responded “I come up with these problems of what happens if I have this issue and I only have this set of gear and I make do and figure it out.” This is the gear fallacy. The idea that every problem you have can be solved by having more gear or using the gear you have in different ways. Canyoners seem particularly susceptible to the gear fallacy, whereas the issue is not that you have insufficient gear, it’s that you are not thinking accurately about the situation. Interestingly enough, this particular accident is one of the few that actually could be prevented by using more gear. Back up the anchor or put in a second bolt. Consequence, probability, exposure and vulnerability all managed by one action.
The third member of the party when asked about risk said “just trying to work out what could possibly go wrong and how I can fix it.” This isn’t a bad answer but is a little bit arse backward because fixing things after they have gone wrong is appropriate for error correction but not for risk mitigation.
Risk mitigation is actually about assessing probability, consequence, vulnerability and exposure and modifying these constructs to plan and conduct an adventure that fits within your own acceptable risk. There’s a very good Tedx video here which presents these concepts in a model suitable for outdoor adventurers. In the video, Statham describes a complex ascent of a large mountain where the usual camp for the summit attempt was under a large ice cliff. Dozens of parties had camped in the exact same location but Statham’s crew deemed the consequence catastrophic even though the risk was low. They used a different summit day strategy and avoided the camp.
But it’s hard to appropriately assess a risk mitigation strategy if you don’t first recognise the risk. This seems to have been the issue with the canyoning party. The concept of a single bolt anchor failing was never seriously considered so no mitigation strategies were considered. And it’s easy, in the excitement of the day or the even the pressure of time to push forward without considering the edge case – the high consequence, low probability, high exposure and vulnerability event – when suddenly, your best day ever becomes your worst.
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