River Rapid Classes 101

Submitted by Tech Support on
River Rapids Class scale

Idaho river rafting season is upon us and there is no better place to launch from that Stanley, Idaho. But before you hop on that raft, take a minute to become familiar with the classes of river rapids.

How Difficulty is Determined

River experts use the International Scale of Difficulty for ranking different types of rapids. The rankings start at a Class I and progress to a Class 6, which is almost impossible to finish and requires great skill. It is important that a person choose the right classification number that is equal to both their skill and comfort level. It is part of being safe on the river and can save lives.

Rapid Classes

The different rapid classification include:

  • Class I: Easy—Defined as fast moving water with some small waves. It has a few obstructions, which are all obvious and easily missed with a little bit of training.
  • Class II: Novice—Considered straight-forward rapid with clear channels and can be seen without scouting. There may be some occasional maneuvering required, but rocks and medium-sized waves are easily missed.
  • Class III: Intermediate—Moderate to irregular wave height and may be difficult to avoid. Complex maneuvers also may be in order in this type of rapid.
  • Class IV: Advanced—Experienced guide is highly encouraged at this level. Don’t enter a Class IV rapid without an experienced guide at the helm. The degree of difficulty has gone up substantially on a Class IV rapid and required some expert maneuvering. Scouting on these types of rapids may be necessary the first time down them.
  • Class V: Expert—Class V is the second to highest class you can strive for in the rafting community. It may also be the hardest rapid that is regularly doable, as anything higher is almost seen as impassable. These are very demanding rapids that should only be attempted by experts and are very long, obstructed, or violent.
  • Class VI: Extreme—These types of rapids are typically just to look at, as they are attempted very rarely. The consequences of error are quite dire, and rescue may be considered impossible. If these types of rapids must be tried, they should only be done by true professionals or a team of professionals.

If you have any further questions on the classification system or rapids, contact your local outfitter. If you need transportation to get to Stanley, you can contact us!