River difficulty is rated on a scale from Class I (the easiest) to Class VI (the most difficult).
For those unfamiliar with this system, a simplified version is in order:
- Class I: Still and gently moving water
- Class II: Whitewater for the informed novice. Currents, small waves, and obstacles.
- Class III: Whitewater for the intermediate boater. Medium-sized waves, fast current, and obstacles that need to be maneuvered around.
- Class IV: For the expert boater. Large waves, very fast current and difficult maneuvers.
- Class V: Difficult even for expert boaters. Involves scouting, long rapids, extreme turbulence, and perfect boat control.
- Class VI: Not navigable, or the most extreme of river running stunts.
So how is it that a first time rafter can go on a raft trip with Class IV expert water? Because you have an experienced guide who can recognize the river’s best line and direct the raft through turbulent waters with relative safety, without difficulty.