The Red Bull Qiantang Shoot Out 2013 returns to the Qiantang River, in China, the most unusual wave in the world for a surfing contest.
This is probably the first ever competition held on a tidal bore. The Red Bull Qiantang Shoot Out pits teams of surfers against each other in a river wave.
"You have only one wave per day to work with, a limited number of days that it breaks and you have to keep the officials and crews ahead of the wave as it moves upriver at over 40 km/h", explains Glenn Brumage, contest director.
"As well, most of the world's tidal bores are limited by size, 'surfable' faces or accessibility. Luckily for us, the Qiantang wave is unusual in its size - recorded at 9 meters -, its variety of workable faces and its path through the middle of the city of Hangzhou".
Teammates alternate drop off either by tow in or step off and move off the wave face to await the end of their mates ride, at which time they will switch positions and be dropped into the next opportunity.
The contest venue presents a number of wave faces. Teams take turns down the river as faces present. First priority is given by coin toss.
Obvious hopping, interference or wakes on the wave face result in a "no score" for that section and possible deduction for flagrant or dangerous behavior.
"The Qiantang is huge and the riverbed is constantly changing. Tons of sand moves down the river all year and the forces of the current and tides create different sand bars and channels constantly. Add to that the curving 'dragon' shape of the river course and you get a constantly changing contest arena", adds Bao Xuping, a Hangzhou local surfer.