looks like a fair volume of water moving through there. A bit OT, but the Eskimo roll is not that hard once you understand how it works. You dont use the paddle to pull yourself up (unless you have been taught a dodgy lever technique). The paddle just gets in the way... the trick is to flick the boat up by slowly arching your body to one side (toward the surface) about the hips, then rapidly flicking the other way (head into the water). Body inertia is more than that of the boat so the boat rotates faster than the body. Then there is some natural stability in the boat which helps to keep it upright. The paddle can then be used at the end to get some support. This guy's paddle has a low surface area so he needs to feather it pretty fast to get any useful lift out of it. But it would make a nice efficient rudder in moving water.
Heres another example of a tidal race, but this one is popular with the freestyle kayakers since it is very stable
