The packraft, a small, agile and lightweight landing stage rivers are becoming increasingly popular with whitewater and stillwater adventure enthusiasts. However, rivers are wild and unpredictable environments where certain hazards can go unnoticed but prove fatal. Let's take a look at 4 risks, often difficult to detect, that you need to pay particular attention to if you want to navigate safely.
Siphons: invisible obstacles, deadly hazards
A siphon is a formidable trap, often invisible at first glance. This phenomenon, whether natural or man-made, consists of a current that pushes water below the surface, creating a zone where floating objects can be swallowed up and sucked down. Deprived of air, the swimmer risks drowning if he doesn't free himself quickly.
Natural siphons generally form in specific geological areas such as canyons or rocky riverbeds, as in the Verdon.
Others, however, are man-made, linked to hydraulic installations such as dams. Sometimes, a siphon can manifest itself in a more insidious way if the installations are degraded or under heavy flooding. Vigilance is therefore crucial: if the water is abnormally calm in a place where the current should be strong, this may indicate a siphon hidden beneath the surface.
Reminders: the trap of aquatic recirculation
Another deadly river hazard is rappel. This phenomenon occurs when a waterfall generates a depression at the surface, creating a recirculation zone. Objects or people caught in this spiral of water can become trapped, shaken by the waves and prevented from returning to the surface. The violence of the fall and the sheer force of the water make evacuation all the more difficult. Abseiling can also be natural or artificial. Artificial rapids, created by dams or hydraulic structures, are particularly dangerous because of their uniformity and the difficulty of escaping. In periods of high water, they can become even more powerful, posing a real threat to packrafters. Keen observers will recognize a rappel by studying the water movements after the fall: a circular flow on the water signals that recirculation is in place. If you're a beginner, it's advisable to avoid vertical falls, especially those caused by human development.
Ice jams: fatal obstacles hidden in the current
Logjams, or "sieves", are piles of branches and trunks that form after floods or landslides. Often visible under bridges or upstream of natural obstacles, these structures may appear harmless. However, they represent a mortal danger, as they allow water to pass through while capturing floating objects. If they pass under the surface, it becomes virtually impossible to free oneself from the current's embrace. Logjams can form naturally, as in the case of uprooted trees, or be caused by human constructions, such as fences, cables or nets that obstruct the river. The areas most at risk are those subject to torrential flooding or major seasonal changes. A logjam can be difficult to spot, especially if the branches are submerged.
Undercuts: an insidious underwater trap
Undercuts are areas where the river's erosion has hollowed out the rock below the water level, weakening the structure above it. These formations can lead to the creation of underwater caves, dangerous spaces to be avoided. Although they are often found on the outside of bends where the water has eaten away at the bank, they can also be found in more surprising places, such as on the upstream sides of rocks in mid-stream. A warning sign is strange water behavior: a pressure wave where you least expect it, or a flow of water that seems to be creeping into a cavity below the surface. If a whirlpool seems absent in a place where there should be one, it's a clue that a trap could be lurking beneath the water. Caution is advised.
Anticipation: the key to packraft safety
Preventing packraft accidents is above all a question of careful anticipation. Knowing what the hazards are and how to spot them enables you to sail in complete safety, well before you take to the water. Proper preparation consists of 3 essential phases:
- Before embarking: find out all you can about the route. Consult the guidebooks, ask local clubs or guides about potential risks, such as siphons or abseils. This preparation can save you from many unpleasant surprises.
- Before arriving at the obstacle: on site, carefully observe the watercourse and any possible changes in its behavior. Visual recognition can identify imminent dangers such as areas of turbulence or unusual currents. Be ready to communicate with your team-mates to adjust the trajectory.
- Before crossing the obstacle: don't rely on your view from the boat. Take the time to analyze the terrain and identify areas where you can pass safely. If necessary, portage your boat around dangerous obstacles.
