International Scale Of River Difficulty

International Scale of River Difficulty 


So you’ve discovered a great creek in the backcountry and you can’t wait to try out that new playboat of yours. But not so fast. Before venturing out onto unknown waters, you’d better find out what you’re getting yourself into. Talk to someone who’s recently paddled that creek. If that doesn’t work, talk to someone in the forestry department and see if you can get some current info on water levels and the category of rapids you’ll be facing.

As you’re probably aware, there are several categories of rapids as defined by the International Ratings system. They are:

  • Class A: Lake water. Smooth as glass, with no perceptible waves or other movement.
  • Class I.- Easy. Your parents would like this one. Smooth water with a few light riffles. Gentle curves, shallow drop,
    and an occasional sand bank thrown in to keep you awake.
  • Class II.- Moderate. Fairly swift water, rapids with regular waves, some rocks but with clear and open passages between them. No problem for paddlers with intermediate skills.
  • Class III.- Moderately difficult. Now we’re beginning to have fun. Look for numerous high and irregular waves, rocks, and eddies. The passages are clear but narrow and can be tricky to handle. When in doubt, a visual inspection is a good idea. These rapids are best left to paddlers with good to expert skills.
  • Class IV- Difficult. Extended and powerful rapids with standing waves in this class. Even more challenging when boiling eddies and deep holes are tossed in. Expert paddling skills are required here, and visual inspection from shore is mandatory. And don’t forget to plan for possible rescues before taking on Class IV water.
  • Class V- Extremely difficult. Look for long, violent rapids that extend without interruption. Steep drops, strong currents, and a river full of obstructions. This water can only be run by experts, and only after making rescue preparations. Leave the parents–and everyone else without top-notch paddling skills–back at camp.
  • Class VI.- Extraordinarily difficult. Even world-class paddlers take this water on with trepidation. Extreme danger here, and these rapids are only navigable when conditions and water levels are perfect. Stay away from these rapids unless you’re an expert, and you’re willing to risk life and limb in the attempt. And make sure to take every safety precaution.



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About Julian Thompson

5b01f5332e506e323531e6a43cda71ee?s=90&d=mm&r=gJulian Thompson is a kayaking expert that has been kayak fishing for over 12 years. He prides himself on his knowledge of lures and trolling motors. He lives in Newark with his two kids and spends weekends on the lake in his favorite Hobbie Outback.