
Further to Bernie's post re the kayakers at Llyn Brianne spillway, Wales Online also has a story on kayakers zipping down the 1:3 gradiant at 70 kmh.

These pictures were taken by James Davies as he passed by on Sunday afternoon. An onlooker is quoted as saying, “They zipped down at incredible speeds then disappeared into a mass of white water only to surface seconds later, apparently unharmed. I just could not believe people would have the nerve to paddle to the top of the spillway then calmly shoot over and downwards towards a virtual sheer drop.”
The article qutoes the power company which of course forbids this sort of activity at their facility.
But the article also quotes Richard Harvey, the chief executive of the Welsh Canoeing Association, who, while acknowledging the risk of extreme kayaking, says, "We are not policemen and we are not some kind of nanny state. If no-one else is going to be harmed and the environment does not suffer, people can make their own choices. Some people just want thrills and when it comes to being in a canoe going down such steep gradients it is hard to draw the line between canoeing and sledging."
While this looks really fun, it also looks really dangerous. These people are taking quite an impact at the bottom of the run.
But you can't outlaw stupidity and/or adventurism, and there's often a very fine line between the two. It's usually an adventure only up until the point that someone breaks a neck. Then it becomes stupid.
Still looks like fun, though.
A quick search on Youtube reveals some videos of kayaking Llyn Brianne, including this short clip of a run filmed with a helmet cam.
And here's the clip referenced in Bernie's post that the Beeb won't let you embed. (Bad Beeb.)
And while we're debating the merits of adventure and stupidity, I came across an article with some great pictures of Pat Keller going over the 40m drop at La Paz in Costa Rica ealier this year. There's some amazing pictures of it here.