The Bad Holes

You spend the first half of your paddling career trying to stay out of holes, and rest of your paddling career trying to stay in them.

How to Read the bad holes

You spend the first half of your paddling career trying to stay out of holes, and rest of your paddling career trying to stay in them.

The expression is a daunting joke to rodeo competitors… but seems to be quite true for most paddlers. The less you know about holes, the more frequently you seem to get stuck and trashed. The more you know, the better you are at picking ones within your ability.

The Basics: Wave Holes And Ledge Holes

Holes with more of a wave shape are intimidating, but typically less hazardous. Very little water is recycling back upstream. Even the huge wave holes will usually just tumble you a time or two before flushing you out.

about hydraulic in river

Ledge holes are not so nice. These go by different names… like pourover, keeper, sticky hole, etc. The water drops down, goes underneath, and some recycles back upstream. This water moving upstream can be tricky, and hold a boat, and in some cases if you swim. Learn how to identify the ugly ones so you can avoid them.

Big Backwash Is Bad

hole backwash

The distance the water in a ledge hole is moving upstream tells you a lot about its danger and power. If the backwash is approaching four feet, there is a greater chance you can get recycled in there if you swim. If the current moves upstream a greater distance, it is getting really nasty and dangerous. A ledge hole with only 2 feet of backwash, might be pretty sticky for a boat sidesurfing, but as soon as you swim it will flush you out pretty quick.

Irregular Is Better

A hole or ledge hole that is irregular is nicer, since there is more likely jets of current breaking through the backwash. Hook up with one of those irregular spots, and you are on your way out. If the backwash is wider, stretching across more of the river, it is worse.

Width Is Worse

dangerous dam

The worst examples are low head dams, which often have dangerous hydraulics because they are wide, have several feet of backwash, and no current blowing through. If you look carefully, you can spot the horizon line from upstream. A ledge hole that is only a few feet wide is less dangerous, since it won’t take as much effort to swim out the side.


Smiling Or Frowning

holes shape

Whoever thought of this famous memory trick must have been in a helicopter at the time. Smiling or frowning refers to the view looking upstream from overhead. Basically, if the ends of a hole are angled downstream, it will tend to feed you out the end. A frowning hole has the both ends angled upstream, and is worse, more likely to hold you. This one is smiling.

A hole that is angled relative to the current flow will be more friendly, since it will tend to flush you out the side into the current rushing by.

Rare Exceptions

If the ends of the hole are closed, like angled upstream or against a wall, it can be real sticky and bad.

Another exception is a hole with unusual power moving back upstream. These are rare, but the worst examples have a rock underneath, aiding the backwash. Some low head dams are designed with this feature, making them extra dangerous.

What to do

Smart paddlers don’t ever run drops blindly. When you can’t see clearly downstream, either to the end of a rapid or the next sure eddy, stop and get a better view. Scouting is always a good option, and a good opportunity to share knowledge!


Swimming in holes can be big fun with the right wave hole... but in larger pourover holes its no fun. If you feel stuck in one don't just swim for the surface! Simply changing your shape may cause the hole to spit you out.

First, swim aggressively for the sides where water rushes by. You may improve your chances to escape if you swim upstream to hook up with current flushing out underneath.