Canyoning in the Alps. Simon Flower

and prepare for their eventuality.

      High water

      Drowning remains the number one cause of death when canyoning. Sudden flooding is the main culprit (see ‘Sudden flooding’, below), and in addition many people underestimate water levels even before committing themselves to a descent. Prolonged periods of rain or a wet spring mean that the canyons will be wetter than normal in the summer, thus increasing their difficulty above the grade quoted in this guidebook. Get an idea of the water levels in the area before attempting more difficult canyons. Keep an eye on the weather a week or two before you arrive, and bear in mind that the flow rate in dam-regulated rivers may change over time (see Route 54 Grigno or Variola Inferiore, in Route 4, for a case in point). Comparing current flow rates in rivers with historical data is a useful trick, but such data is hard to find and will not be easy to access when abroad. For Ticino, hydrological data is available at www.bafu.admin.ch.

      An unavoidable soaking in Clusa Inferiore (Route 59 in the Belluno Dolomites)

      The main white-water hazards are turbulent plunge-pools. The high air content in white water renders it very difficult to remain afloat or swim in, while downward currents at the base of waterfalls and at the pools’ edges can actively drag a person underwater. Such hazards are better avoided than tackled head on. This can be achieved either by jumping clear of the danger (a solution with obvious risks) or by manipulating the abseil trajectory using deviations or guided abseils (see ‘Canyoning rope techniques’, below). Strong currents elsewhere may sweep people over waterfalls or dash them against rocks. If carried by the current, lying on your back, feet downstream, will reduce the chance of serious injury. Watch out for siphons, potentially lethal hazards that lurk hidden among submerged boulders. The gaps between the boulders create strong currents which can suck body parts in, trapping people underwater.

Sudden flooding

      Flooding can be caused by heavy or prolonged rain, snow-melt, or the release of an upstream dam. It is important to assess the risk of each before setting out. If waters rise seek high ground (dry vegetation and trees are a good sign) and wait. Do not be tempted to push on downstream until water levels have returned to normal.

      Rainfall

      Significant rainfall is brought about by frontal systems and afternoon storms. Fronts may bring prolonged periods of rain to large areas of the Alps, whereas afternoon storms are short-lived and very localised, but frequently severe. The latter are brought about by cumulonimbus clouds, which develop from ordinary cumulus clouds as moist air rises throughout the day, a process accelerated by high temperatures and mountain relief. These storms are more common in northern Italy and Ticino than anywhere else in the Alps, owing to the moist, warm Mediterranean air travelling up from the south. Unlike fronts, which are easy to predict, forecasting afternoon storms is difficult. It is therefore vital to get frequent weather updates and to keep an eye out for cumulonimbus development. Weather reports are available in tourist information offices, campsites and local newspapers. Relevant websites are given in each chapter.

      Floods can make a huge difference to the condition of a canyoning route (left: before flooding, right: after flooding)

      Snow and glacial melt

      Melting snow and ice can lead to dangerously high water levels as the day heats up. This is mainly a problem of canyoning early or late in the season. Few canyons in this guidebook have significant snow fields present in their catchment areas during the summer months.

      Presence of upstream dams

      Many canyons in the Alps have hydroelectric constructions somewhere along their length. Surprisingly, given the growing popularity of canyoning as a sport, it is difficult to find definitive information on their purge/opening patterns. Put simply, there are three basic types of construction

       a grill in the stream bed which pipes away water to a nearby reservoir or power plant

       a small dam that traps water first before piping it away

       larger-scale dams, holding back millions of cubic metres of water, which is piped off to the power plant. Water may be piped into the reservoir from a number of sources.

      When a single river intake closes (due to obstruction, malfunction or maintenance purposes), the water normally diverted away will return to the natural riverbed. Unless the river is large this is unlikely to cause problems for the canyoner. If the whole power plant needs to be shut down, or if rainfall is especially heavy, even the larger reservoirs fill and may be forced to open their overflow gates. A release of such vast amounts of water would be disastrous to unwary canyoners downstream. The smaller dams are also dangerous. They may be ‘purged’ after rainy periods to flush away sand and other debris that could otherwise harm the system. In short, the flow of a river below a hydroelectric installation may suddenly increase without warning, even in times of good weather.

      In Switzerland it is usually possible to ring somebody to determine the risk of the dam opening (although the hydroelectric companies still decline all responsibility). In Italy this sort of service is by no means standard, and a certain degree of risk often has to be taken.

      Jumps and toboggans

      It would be fair to say that anyone who wasn’t prepared to jump or toboggan anything wouldn’t be getting the most out of this sport. As well as being great fun, these techniques speed progression and, in certain circumstances, may actually be safer than abseiling (for example, if an abseil deposits you in the worst of the current). That said, the Fédération Français de la Montagne et de l’Escalade (FFME) reports that half of all rescues arise due to misjudged jumps, with a smaller number attributed to toboggans. Injuries are more likely with jumps over 4m. Abseil to verify pool depth if there is any uncertainty. Note that canyons can change drastically over time – pools silt up or fill with detritus washed down by floods. To reduce the chance of injury, jump with legs together and slightly bent, flexing on entering the water. For toboggans, keep feet together and elbows away from the rock.

      Jumping is a useful technique and great fun, but it carries obvious risks (Route 82 in the Carnic pre-Alps)

      When toboggans go wrong! The 20m toboggan in Combra (Route 27 in the Ticino region)

      Waterfalls and abseils

      Use a hand-line to approach exposed pitch-heads, and clip into the anchor while rigging. Tie long hair back to reduce the risk of it being sucked into the descender. Although sharp edges can damage ropes, the majority of abseil problems arise due to high water (see ‘Canyoning rope techniques’ below).

      Slippery rock

      Falls resulting from slippery or loose rock account for about a third of all canyoning injuries. Some rock types provide good friction but become slippery when wet, particularly when covered in a layer of algae. Good shoes are essential (see ‘Equipment and clothing’, below). Be sure to test out their grip when first entering the canyon.

      Rockfall

      Rockfall is a greater risk in drier canyons, where loose rocks tend to loiter at pitch-heads. Rocks also get thrown in from above and blown in on windy days (when it is better to avoid tightly encased canyons).

      Hypothermia and exhaustion

      A warm, well-fitting wetsuit is essential (see ‘