Holes (AKA: Souse Holes, Hydraulics) are caused by a depression in the river bed like water flowing over a boulder. Water cascades over the boulder (or ledge) forcefully downstream and water from downstream flows back upstream to fill in the depression. We often refer to holes as Smiles or Frowns. If the ends are out flowing downstream (Frown), you can exit the hole on either end. If the ends are facing upstream (Smile), exiting the hole isn't as easy. Upstream ended holes typically have a jet stream underwater that you can catch with your paddle or body to forcefully pull you down and out. A perfectly uniform hole - straight across like one formed by a dam can be very difficult to escape and often requires assistance. Smaller holes are often used like eddies by advanced paddlers. Play boaters (and squirt boaters) love holes as this feature enables the many tricks they like to perform. Notice the picture of Big Nasty on the Cheat River.

Play boaters absolutely love holes. This feature is where they can perform most of their tricks. Anyone venturing into class IV whitewater needs to be very comfortable surfing holes (just like class III boaters need solid boat reading skills, eddy turns, and ferry skills). The following video is excellent at describing basic hole surfing technique: Basic Hole Surfing Technique.

One type of hole we ALWAYS stay away from are those created by low head dams. These manmade structures create a perfectly uniform hole that you can't escape from. The backwash is often many yards downstream and very powerful - even motor boats are helpless once caught in the backwash. The following video is well worth watching to understand why these types of dams are so dangerous: Low Head Dam Video.