Whitewater Ratings: Class I to Class V and everything in between

By Sensei Dan Thurber, Packraft Swiftwater Safety Instructor. Read Dan’s other article, “How To Figure Out Your Perfect Packraft Paddle.”

This is an excerpt from The Bikeraft Guide, and so is a guide on whitewater ratings specifically directed at bikerafters. However, it’s still provides a valuable explanation of whitewater ratings for all packrafters.

Rivers around the world are often rated on a scale of 1-5.  This scale is a pathetic attempt to capture difficulty, hazard and exposure into an over-simplified rating system that fails to capture the diversity of whitewater or the dynamic nature of rivers with variable flow. But hey, it’s what we’ve got. Since it’s universally used, it’s worth knowing something about.

Flatwater bikerafting is a great way to start your bike and packraft adventures.
Flatwater bikerafting is a great way to start your bike and packraft adventures.
Class I bikerafting on the Animas River. Photos by Steve Fassbinder.
Class I bikerafting on the Animas River. Photos by Steve Fassbinder.

Bikerafting 101: Whitewater Ratings

Class 0

Still water.  Lakes or inlets. Flatwater can still be dangerous, as we talk about in the next chapter.

Class I Rapids

Easy peasy, once you learn and practice on flat water. May be moving fast and have small waves and riffles. Few, easily-avoidable obstructions. Self-rescue will be simple (once you learn to self rescue) and swimming is not very dangerous unless you (stupidly) aren’t wearing a PFD, choose to stand up mid-stream, or if the water is cold enough to make you hypothermic.

Class II Rapids

For novice bikerafters. Offers straightforward, moderate rapids with obstructions (rocks, minor holes, strainers), easily avoided by experienced bikerafters. Sometimes Class II gets rowdy and flips you, at which time it may be harder to right and get back in your boat without help.

Typically you won’t get hurt or die unless you: 1) aren’t wearing a helmet, PFD or drysuit in cold water; or 2) you’re being an idiot and you try Class II with no practice or training.

Class III

For intermediate boaters. Bigger, more complicated rapids, faster water and strong and/or smaller, difficult to catch eddies. You may have to maneuver through or around tight passages, run steeper drops and larger waves, and avoid strainers. But all these things are manageable with sufficient experience.

Do not get on Class III until you are very proficient in Class IV without a bike on your boat, lest you drown. And don’t expect much help, as everyone else will also be thrashing about. Also, with a bike strapped on your boat, more components can catch on strainers or smash into rocks, or wreck your boat/bike or entrap you, ruining your life, ultimately.

Class IV

Don’t even think about it.

Class V

If you try to bikeraft Class V, you’ll probably die.

Class VI

A portage.

This is what you should be doing if it's Class IV or harder!
This is what you should be doing if it's Class IV or harder!

And Don’t forget…

To further increment the scale, boaters will often embellish a rating with a + or -.  Class II+ is harder than class II, but easier than class III-, and so on. 

River sections are typically described by the difficulty of running 95% of the river.  If that other 5% is harder, that is sometimes described in parentheses.  For example, class II(IV) means it’s a class II run that may have one or two class IV rapids.  Class III(V,P) is mostly class III, but features a class V drop and a mandatory portagage.  Be careful!!

Final Note

Of equal importance, but ignored by the rating system, is the continuity of the river.  Some rivers just keep going, others have isolated rapids ending in long pools which make recovery from a spill much easier.  Running a class II river with big pools may be much easier than a class I river that never slows down.  Do your research.

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