Scale of Difficulty
The river classification system is an internationally recognized rating system to inform whitewater rafters and kayakers as to the level of difficulty for a stretch of water. The scale begins with the easiest water to navigate, or Class 1. The scale progresses in difficulty to Class 6, which indicates the water is impassable and the boat should be carried.
River Classifications
Class 1 whitewater indicates there are no major obstacles in the water and the water is relatively smooth; it is appropriate for all skill levels of paddlers. Class 2 represents water with some challenge and no major obstacles; it may still be enjoyed by a wide range of individuals. Class 3 indicates more challenging whitewater with longer and more technically challenging stretches of white water. Some degree of skill and knowledge is required to navigate some of the currents. Class 4 water is very difficult and will feature much longer stretches of whitewater and strong currents. Paddlers will be required to exhibit strong technique to navigate Class 4 water. Class 5 may feature very long and turbulent runs of whitewater, drop offs, strong eddies and currents, as well as some obstruction in the water. Extremely strong skills are required to navigate. Class 6 water cannot be paddled. The water is too dangerous for kayak or raft travel, and boats should be carried.
Considerations
The classification of a stretch of water may change with the seasons. For example, a river may be a Class 2 in the late summer or early fall as the water level may be down due to lack of rain or drought. However, in late winter or early spring there may be enormous amounts of water feeding the river from snowmelt. The river can rise well beyond Class 2 to a Class 5 or even 6. Make sure to check local conditions and get reliable information prior to planning or beginning a river trip.