California Whitewater Classification System
When I am guiding a boatload of kids down the South Fork of the American River and we hit Barking Dog Rapid, all the kids in the raft scream as they are doused with water and ask with surprised expressions "What level was that one?!". It is always fun to see their re-action when I say "That was a two". They know we are going to hit some class III rapids later in the day and because Barking Dog felt so big they start getting ... well... a little nervous. This is the part of the day where I usually end up explaining the whitewater rafting classification system used in California and in most of the country and around the world. In fact almost everywhere uses this system except for on the Grand Canyon, in Colorado. After I have explained the system to the kids they are usually a lot less scared albeit curious about the excitement that lays ahead.
Class I Whitewater Rapids
Class I rapids are a lazy gentle part of the river with swift moving water in an unobstructed river way. Often referred to as a riffle. On the South Fork of the American riffles are often un-named but on other rivers with longer navigational histories they are often named, like Mule Creek Riffle on the Rogue River . It is usually very easy to navigate a class I rapid with little training. At River Runners we often let guests swim through class I rapids but still treat the rapid with caution. Your guide may tell you to swim away from certain features like a tree branch in the water that could pose a danger to you. A class I rapid is generally easy to swim in with a life jacket on.
Class II Whitewater Rapids
Barking Dog on the South Fork of the American River is a Class II rapid. Class II Rapids are great place to play and surf a raft or kayak. There is swift moving water often with some sort of feature like a rock to avoid or a simple chute to descend. Navigating class II rapids with ease requires some sort of experience but can be accomplished by novice paddlers often with some harmless bumping and bouncing. The waves in Class II rapids can be of a remarkably fun size and can definitely capsize a kayak or canoe. At River Runners we facilitate swimming some class II features for guests who want more of a thrill. These swimming rapids are generally straightforward waves that require little maneuvering to swim. Class II rapids are playful unless of course there is some sort of temporary obstruction like a tree that poses a danger in which case swimming is not advised.
Class III Whitewater Rapids
Class III Rapids are class fun, but treated more seriously than Class II rapids as the potential for involuntary swimming is higher. Class III rapids require training to navigate. Some Class III rapids are trickier to navigate than others like Meat Grinder on the South Fork of the American River which is harder to navigate than Hospital Bar on the South Fork of the American River even though Hospital Bar feels like a bigger rapid than Meat Grinder. Class III rapids have bigger waves and bigger features than class II rapids. There are usually fewer paths a guide can take through a class III rapid because of obstructions in the river. Falling out of the boat in a class III rapid is not unusual so if people do fall out in a Class III rapid don't be scared! Rescue is relatively easy and injury in class III rapids is rare. Some guides even swim them for fun, we don't recommend you do though! Before every class III trip you will be given a safety orientation so that you understand what you need to do to avoid falling out of a boat and what you need to do if you do fall out of a boat. River Runners Guides love taking guests on the South Fork of the American because it is so playful. It is easy to step up the thrill for people looking for a wilder exciting adventure and to tone it down a bit for the more mellow or nervous crew.
Class IV Whitewater Rapids
Class IV Rapids may put you a little on edge, especially if you get out to scout so the guides can see the line is clear and get you all pumped up for the descent like at Tunnel Chute on the Middle Fork of the American River. There you are standing on the safe end of a rapid and then you find yourself walking back to your boat wondering what you got yourself into. It's worth it! Class IV rapids are still fun but it is a much more serious sort of fun. You may finding yourself holding your breath or being out of breath after paddling so hard like you have to on the Kaweah River. Class IV rapids are usually created by a constriction in the river, gradient and/or a feature like a big rock the water pours over or around. Skilled and experienced guiding is needed in order to successfully navigate class IV rapids. With the right guide (at River Runners we only put you with the right guide) you will make it down with a rush and wonder how the boat made it through such a tight spot! Even with the right guide though, it is still normal to fall out of the raft sometimes. The river is such a dynamic environment, these things happen. Before your trip we will give you an orientation about what to do if this happens, you may be required to swim and participate in your own rescue.
Class V Whitewater Rapids
Class V. Oh Class V. People say it's fun. And yes it is fun but sometimes it's fun in the same way shooting yourself in the foot with a paintball gun is fun. Oh okay I am kidding but seriously Class V is nothing to joke about. Sometimes a rapid gets a class V rating not because it is difficult to navigate but because it is really dangerous for a human body to be in there like Fist Rock on the Russell Fork in Kentucky/Virginia. Sometimes a rapid gets a class V rating because it is really difficult to navigate but not particularly dangerous like Charlie's Choice on the Upper Youghiogheny in Maryland. Often self rescue is really difficult in a class V or on a solid class V run where the river is moving from one rapid to another really consistently. Assisted rescue can also be difficult and/or impossible.
Class VI Whitewater Craziness
There are some rapids out there that were thought to be un-raftable and now with evolved skills and equipment people have rafted them or kayaked them and they are considered class V. So a class VI rapid is like a "maybe we will make it - maybe not". Transitioning a rapid from VI to V are often controversial. Take Ruck-a-Chucky on the Middle Fork of the American for example. Ten years ago rafters emptied their boats of guests and the guests helped the guides carry the boats around the waterfall. Now the guests still get out but the guide often takes the boat over the falls by themselves in what is called an R1 configuration. So yeah it is considered run-able but taking a boat load of paddlers over the falls would be considered exploratory rafting and this really keeps it lingering between the class V and Class VI class.