English: Surfing on the Tryweryn The Afon Tryweryn is a dam-controlled river with releases designed to maintain the level in the River Dee downstream. Canolfan Tryweryn takes advantage of this as a whitewater centre by offering courses for canoeing and rafting. In line with the Welsh Canoeing Association's policy on access, CT no longer charge canoeists for recreational access to the river during a release (although parts of the river may be reserved for centre activities), so many paddlers now use the river when a lack of rainfall means that other North Wales Rivers are out of condition. The normal release is 9 cumecs (the minimum for rafting), which is what was flowing from the dam on the day this photo was taken, although the level was highish further down the river owing to overnight rain. Downstream from the centre is a relatively easy stretch of river, on which this ledge drop (just before a roadbridge) provides an excellent opportunity to surf. The wave is quite forgiving at this level, whilst still having enough potential for a few good moves.