Holes are features on the river where the water on the top of the river flows upstream. Generally, under the surface of the hole the water flows downstream, creating a hydrolic cycle effect. Some holes can be safe and great fun. These are what freestyle kayakers tend to use. Other holes can be extremely dangerous as they can hold a kayak and in some situations a swimmer and allow no chance of escape.
How to get out of a hole
Sometimes if you place your paddle deep in the water you can grab enough of this downward flowing water to be able to paddle out of a hole. If you are caught in a hole, edge your boat downstream so that your upstream edge does not catch and flip you. The stronger the hole, the more edge you should use. If you can, work your way to the edge of the hole so that you can move back into the downward flow.
If you are swimming in a hole, chances are that if you can not swim out of it, you may have to either swim to the edge of the hole to get out or if nothing else is working curl up into a ball and allow yourself to go under the water and catch the downstream moving flow.
Holes can be a tremendous playground, but they can also prove to be a major hazard. You need to use judgement and rely on experience when deciding which holes are ok to paddle into.
Look at the river features section to find out more about recognising smiling v’s frowning holes. Theres also information on how to use the boil line and the entry angle of the green water to distinguish between a friendly and a dangerous hole. You can always use the good old ‘log test’ and toss a large branch in (to a hole) to see if it gets held.
This is not an exact science so when in doubt avoid a hole that you are uncertain of.