About Tatshenshini Canyon
A yellow/white cliff on river left is a good marker for the Canyon. From here you are about half a mile from the first rapids. Given the remoteness and heavy boats, this section is solid Class III- IV at low/medium water and Class IV-V at high water. If you own a drysuit or drytop this would be a good day to wear it. You might only need it for one day, but solid dry wear and a high float PFD will make a huge difference if you end up swimming. All boats should be rigged to flip, with rescue, first aid, and repair kits easily accessible. Spread the weight out equally amongst the boats so nobody is too overloaded.
For rafters, none of the moves are particularly difficult, but heavy boats and few eddies to regroup enhance the challenge. While avoiding the more obvious hazards like holes and boulders, it is also vital to stay off the walls. Issues arise when rafts get too far outside in the corners and puncture a tube on the cliffs. Limping into camp the first night to repair a boat is not a fun way to start the trip. If anything major did occur in the canyon, there is a road on river left that will take you back to the put-in. It takes up to six hours to walk and is on the other side of the river from the put-in.