This will be your first major rapid after Delongha. There is no good scout. The rapid becomes more difficult as the flows drop as the rock becomes exposed and the setup becomes bonier. The ‘surprise’ is a large boulder hidden in the bottom of the wave train. If the boulder is exposed it’s easy to flip off of.
Above 3500 CFS: At flows above 3500, this rapid is straight forward and practically washed out. Dodge some small holes in the entrance staying in the middle of the river as the river bends right. Drop into the straight away and enjoy the wave train. Stay a little more left to spice up the action.
3500 to 2000 CFS: The entrance starts to become a little more channelized. Be sure to get left as you ride the wave train to avoid Surprise rock as it becomes exposed.
Below 2000 CFS: As the flows drop, some of the rocks can hang you up at the entrance so be sure to follow the main channel. The rock is fully exposed so be sure to get left once you drop in.
This video shows Suprise at 3,400 CFS. You can see how the rock is invisible at the bottom and the entrance is washed out. One option is to enter a little further left for an extra hit
Low flows – sub 1,000 CFS. The rock is exposed and the entrance is a little more tricky.