Sunday, June 13, 2010

Who wants to learn something?

I just got back from several days of river paddling and I'm working on editing the video. I am also working on an article I'm writing for California Kayaker Magazine. It's about paddling with current, be it in the river or ocean. I have a draft completed and was thinking that this would be a great audience to get some feedback from. It's missing some photos and diagrams that I am still working on but I think you can get the idea. Please let me know what you think and if you like it I can post some more technique articles I'm working on.

Get Into the Flow
How to effectively paddle with moving water
By Bryant Burkhardt
Moving water comes in many shapes and sizes and learning to paddle with current can open up more options for paddlers in any boat. Whether you are on a river or tidal flow, in a long boat or short, there are some simple principles to understand and basic techniques that will allow you to negotiate the moving water safely and efficiently.

I began my kayak career on the ocean so when I got around to paddling on the river I already had some basic skills – I could paddle in a straight line, edge my boat a little and even pull off a combat roll. But my lack of understanding of currents meant I used that roll a lot, constantly being flipped by water for no apparent reason. This was because I did not understand the fundamental nature of how moving water interacts with a kayak. Understanding some basic hydrodynamics will go a long way to allowing you to avoid the upside down learning process.

The first thing to understand is that moving water is only important in a relative context – if a boat is moving the same speed as the current then the interaction between boat and water is exactly the same as if both are stationary. It is when there is a difference in speed or direction between the boat and water that the dynamic interaction of the two comes into play. This occurs when a boater is moving from calm water (eddy) into current or vice versa. That transition is the critical moment and we will look in depth at how to handle it.

But first let us look at what happens when moving water hits a stationary boat (which is the same as when a moving boat hits stationary water). If the water hits the boat head on then nothing much is going to happen. The bow (and generally the stern) of a boat is designed to split the water. So the water will be smoothly separated and flow around the boat causing the paddler no concern. But when the water hits the side of the boat it cannot simply go around – the obstacle is too large. In this case the water will pile up on the upstream side of the boat, and this resulting pile of water will catch and push down on that side of the boat causing a twisting force that wants to flip your kayak upstream. This is the cause of the majority of flips when learning to paddle in current.

Now let us look at that same situation with current hitting the boat – but instead of a flat boat let’s see what happens when the boat is edged downstream (you can also think of this as lifting the upstream edge). To be clear: I’m talking about changing the angle of the boat on the water, not leaning your body - just the boat. Now the moving water does not run into the side of the boat first, it actually hits the bottom of the boat. Instead of piling up on the side of the boat the water is pushed under the boat. This action will actually push up on the downstream edge of the boat in an attempt to flatten the boat out. This righting force from the water is easily countered by the boat lean that created it and when the two forces are in balance the boat and paddler are quite stable. So understanding how and when to edge the kayak when entering or leaving currents is the key to dealing with moving water.

Eddy Turns
Now that we know that edging is the key and the transition between currents is the critical moment we shall look in detail at how to accomplish this action. The technique is called an Eddy Turn and it is used to go from an eddy into current or from current into an eddy. And to be clear: when I say an eddy I simply mean water that is moving at a different speed from the main current. And the division between the eddy and the current will be referred to as the eddy line. Often eddies appears to be totally calm water but many times the eddy will have a current that is opposite in direction to the main current. Again, the important thing is always relative motion and this technique applies to any transition from water moving at one speed to water moving at a different speed.

We will start with the most common situation and then see how that can be generalized. We will begin in an eddy next to shore with calm water and our goal will be to get our kayak out into the moving water that is going by (be it a river or tidal current). Once we are out in the current and moving at the same speed as the water then it is just the same as paddling on flat water. Only when we look to exit the current and stop in an eddy do we have to again pay attention to current specific techniques.

To enter the current from an eddy one could theoretically just paddle straight into the current. The problem is that when your bow hits that current it will start to turn the boat and since the rest of your kayak is still in the eddy your boat will be spun around before you can cross the eddy line into the current. The solution to this is to start out pointed upstream into the current. While the current will still turn your bow downstream this initial angle will give you more time to cross over into the current and get up to speed while being less likely to spin around and end up where you started. This turning action leaves us pointed more or less downstream and is why we call it an eddy turn and not an eddy cross. But the current does the turning of the kayak – you don’t need to use any turning strokes to accomplish this.

Another important component to crossing the eddy line is speed. The eddy line itself is not always a thin, straight line. The area between the eddy and the current can be several feet wide and quite turbulent. We want to get through such an area as quickly as possible so we want to have as much forward speed as we can going into it. This speed will also give us more momentum which helps to stabilize the boat throughout the eddy turn.

Finally we get back to where we started: we need to edge our kayak as we cross the eddy line and enter the current. From our earlier discussion this edge will prevent the current from catching the upstream side of the boat and flipping it. So we need to edge downstream (lift the upstream edge) as we cross the eddy line and hold that edge throughout the turn. If you drop your edge too early the water will pile up and flip you, whereas if you hold the edge too long there is no penalty. So just keep that edge. It is important to note that this downstream edging throughout the turn is just like leaning into the turn on a bicycle (or skis or surfing or any other sport).

So we have completed our eddy turn and are now in the flow of the current. Once we decide to pull out into an eddy we will use the exact same technique. We just have to look at the relative water speed and adjust accordingly. When you are moving with the current the eddy’s calm water appears to be moving in the opposite direction. Now you need to angle down into the eddy, get up some speed and edge away from that eddy current (once again this is simply leaning into the turn).
These are the three keys to performing an eddy turn: Angle, Speed and Edge. You need all three to be present in order to make a stable transition from water moving at one speed to water moving at another. For faster, stronger currents you will need to increase all three of these: higher angle, more speed and more edge. Each situation has its own perfect combination but after a little practice it will happen naturally (just like riding that bike).


  1. Bryant - A couple of things kind of jumped out at me. You may be planning to use illustrations for these, but you might want to explain the physical act of edging in a little more detail. A true beginner may be left scratcing his head. Also, a little more description of the entry angle when you first mention it. It sounds (to me, anyway) like one is to paddle into the current at at 12 o'clock position. Beyond these quibbles, it's clear and very readable. Good job!

  2. Bryant - bow's the article coming along?

    If you use the composite photo showing the yellow boat entering the current, it may be good to add an arrow showing the current direction. And maybe a line showing where the eddy line is. Perhaps 2 copies of the same photo - one unmarked and the other marked up with current direction, eddyine, etc.

    Maybe in the first paragraph ("many options for paddlers in any boats", add a sentence that talks about how eddys can be used (spot to rest, eddy hopping to move upstream against current, etc.).

    Reminder - deadline is coming up...