River difficulties
Degree of difficulty scale
CANOA / KAYAK
The WW (White Water) scale internationally recognized by the ICF (International Canoe Federation) is divided into 6 grades or classes.
It should be borne in mind that, in a given stretch of river, the difficulties vary greatly with the flow of water (and therefore depending on the season, the rains and the thaw). Abrupt and fast variations, even in the space of a few hours, can be found as a result of maneuvers of locks and / or the effect of sudden obstacles (fall of trees and the like). A river with too low or full flow has no classification. The river area located at the edge of the current, where the water is still or rather rises towards the mountain, is said to be “dead”.
The WW scale is defined as follows:
WW I
Easy
Little-animated bottom, which produces small regular and scattered waves over the entire surface. Light current and any well delimited and avoidable eddies. Rapids wide and not cluttered with obstacles, so the trajectory to follow is linear and well evident. Very modest slope.
WW IV
Difficult
Large and irregular waves, presence of holes to be avoided or overcome with force and decision at the moment and in the right direction. Very hard rapids, to be overcome with good and precise maneuvering techniques. Small and eventful death, in which it is not easy to stop. In the 4th degree, swimming becomes dangerous, and companions can hardly intervene: therefore you must be master of the eskimo in any condition. Very timely preventive reconnaissance before the sections of IV. Rapids are often no harder than in the III, but their length and continuity increase overall difficulties.
WW II
Not difficult
Stream with obstacles easy to avoid, wide and clearly visible death, the descent line to follow is evident even if it requires some extensive maneuver. The descent causes emotion and satisfaction but no fear.
WW V
Very difficult / dangerous
Very deep holes that tend to keep the kayak or canoeist from falling over. Bubbling and unusable dead zones. Rapids obstructed by large boulders, with narrow passages, violent and sudden waves and currents. Indispensable safe technique, promptness and timing, training and a glance. Even for an expert, a grade V stretch is no longer fun, but a difficult and dangerous challenge.
WW III
Moderately difficult
Torrent with succession of moderately difficult rapids interspersed with ponds, waves and holes that can block the descent and also completely immerse the kayak, but without holding it back. Rapids with obstacles that require decisive and efficient maneuvers.
WW VI
Extremely Difficult
It represents the limit of practicability at this point it is no longer just about excellent technique, but also about (excessive) courage and passion for risk. Sometimes someone manages to do some stretch of VI; but in these cases the slightest mistake is fatal.
Tourist descents usually take place on routes up to the III degree; in safety conditions (rallies organized with emergency service) passages or short sections of grade IV may be included. The most prestigious competitive competitions (slalom) generally take place on stretches of grade IV, occasionally V, with adequate rescue service.
