Holes in Rivers
As you progress as a whitewater kayaker, one of the most vital skills you can have is your ability to recognize when a hole on the water is one that will be dangerous or one that will be fun. Since holes can come in all shapes, sizes and strengths it is important to not underestimate a hole in the river.
A hole is formed on the river when water goes over a drop of some sort and the water then pushes down to the bottom of the stream where it continues to flow downstream. The river reacts to this by attempting to fill in the river where the water is flowing downstream. This reaction can often be upstream and creates the whole. It can be known as backwash as well. If you were to look a strong hole from the side you would see the currents in it rotating around like a wheel counterclockwise. Now as there are so many different holes and types of holes, it is important to be able to judge the strength of a hole. The four factors that affect a hole. The first is the type of falls, measured by things like angle, volume and height of the falls. The next three are about characteristics of the hole. The first is the length of the backwash. The backwash is a measure of how far downstream you could drop a piece of wood and would it float upstream to the hole. A large waterfall or hole can easily have a backwash of twenty or thirty feet. The larger a backwash is, the stronger the hole is and more likely it is to trap you! The next two factors are the hole depth and width. Hole depth is a measure of how far down the hole extends beneath the surface. This measure is important to kayakers because the deeper the hole extends, the less chance of escape you have if you flip into the water there.
As for the width of a hole, this is a measure of how wide this is, and the rule to remember is that the wider a hole is, the harder it will be for you to swim out of it and escape. Remember these rules to judge how strong a hole is and your river running will be safer and a lot more enjoyable!
