Editing Whitewater (section)

== Classification ==
{{Main|International Scale of River Difficulty}}
The most widely used{{Citation needed|date=October 2015}} grading system is the [[International Scale of River Difficulty]], where whitewater (either an individual rapid, or the entire river) is classed in six categories from class I (the easiest and safest) to class VI (the most difficult and most dangerous). The grade reflects both the technical difficulty and the danger associated with a rapid, with grade I referring to flat or slow-moving water with few hazards, and grade VI referring to the hardest rapids, which are very dangerous even for expert paddlers, and are rarely run. Grade-VI rapids are sometimes downgraded to grade-V or V+ if they have been run successfully. Harder rapids (for example a grade-V rapid on a mainly grade-III river) are often ''[[portage]]d'', a French term for carrying. A portaged rapid is where the boater lands and carries the boat around the hazard. (In many cases, a lower rated rapid may give a better "ride" to kayakers or rafters, while a Class V may seem relatively tame.  However, it is not so much the "ride," but the inherent danger in the rapid.  An exiting rapid may have minimal risk, while a seemingly simply rapid may have terminal hydraulics, undercut rocks, etc.)

A rapid's grade is not fixed, since it may vary greatly depending on the water depth and speed of flow. Also, the level of development in rafting/kayaking technology plays a role.  Rapids that would have meant almost certain death a hundred years ago may now be considered only a Class IV or V rapid, due to the development of certain safety features.  Although some rapids may be easier at high flows because features are covered or "washed-out", high water usually makes rapids more difficult and dangerous. At flood stage, even rapids that are usually easy can contain lethal and unpredictable hazards (briefly adapted from the American version<ref>{{cite web|url=http://www.americanwhitewater.org/archive/safety/safety.html#rating%20scale|title=American Whitewater – Safety|date=27 July 2013|publisher=Americanwhitewater.org|access-date=30 December 2014}}</ref> of the International Scale of River Difficulty).
* '''Class 1:''' Very small rough areas, requires no maneuvering (skill level: none)
* '''Class 2:''' Some rough water, maybe some rocks, small drops, might require maneuvering (skill level: basic paddling)
* '''Class 3:''' Medium waves, maybe a 3–5&nbsp;ft drop, but not much considerable danger, may require significant maneuvering (skill level: experienced paddling)
* '''Class 4:''' Whitewater, large waves, long rapids, rocks, maybe a  considerable drop, sharp maneuvers may be needed (skill level: advanced whitewater experience)
* '''Class 5:''' Approaching to the upper limits of rapids that can be run with the paddling skill (a Class 6 rapid has more to do with luck than skill, at least skill that can do much more than simply avoid the meat of the rapid).  Whitewater, large waves, continuous rapids, large rocks and hazards, maybe a large drop, precise maneuvering, often characterized by "must make" moves, i.e. failure to execute a specific maneuver at a specific point may result in serious injury or death, Class 5 sometimes expanded to Class 5+ that describes the most extreme, runnable rapids (skill level: expert); Class 5+ is sometimes assigned to a rapid for commercial purposes, since insurance companies often will not cover losses sustained in a Class 6 rapid.
* '''Class 6:''' While some debate exists over the term "class 6", in practice it refers to rapids that are not passable and any attempt to do so would has considerable risk of serious injury, near drowning, or death (e.g. [[Murchison Falls]]).  If a rapid is run that was once thought to be impassible, it is typically reclassified as class 5.