Reading the River
Click on an item for a description.

 
 
 
 

 
boulder sieve  The path of the current through this jumble of exposed rocks isn’t big enough for a raft to pass through safely. Sieves are often found in shallow water at the edges of major rapids. Also called a rock garden or picket fence.

 
 
 
 

 
breaking wave  A wave that moves with such force that the crest curls back upon itself, forming a wall of water. Depending upon the power of the water and the steepness of the wave, a breaking wave can either be a fun splash or a dangerous obstacle.

 
 
 
 

 
CDA!  “Cheated Death Again!”—often heard uttered on the downstream side of major rapids. In the calm water you can dry off, collect your wits, and work on the stories for around the campfire.

 
 
 
 

 
eddy  Skilled boaters use the calm water created behind large rocks, on the inside of river bends, and along river edges as places to rest away from the main current or to position the boat before moving on.

 
 
 
 

 
haystack  Usually caused when the water’s flow is constricted, these powerful, pyramid-shaped waves are the fireworks of most rapids. Harmless but often huge, they seem to jump out of the water. No dangerous rocks lurk here, so most boats will splash through safely.

 
 
 
 

 
hole  A sudden steep drop formed when lots of water flows over a boulder or other obstacle, then curls back upstream with such force that it can hold swimmers, floating gear, even complete rafts for days.

 
 
 
 

 
logjam  Steer clear of this collection of logs and debris, often found where the river flows around the tip of an island or makes a sharp turn. Underwater logs can rip boats, snag the life jacket of someone in the water, and cause all kinds of havoc.

 
 
 
 

 
pillow  This cushion of water often forms on the upstream edge of large boulders. In big rapids the pillow is big enough to shove the bow or stern of a raft safely away from a boulder, a fact that boaters sometimes take advantage of in running a rapid.

 
 
 
 

 
pool  Just upstream of most major stretches of white water lies a large pool of slow, deep water where you can pull over for a scout before the big rush.

 
 
 
 

 
reflection wave  Water takes the path of least resistance—until it meets an obstacle, such as a cliff. Then, all that power pushing the water must reverse itself, causing waves to bounce off, often at strange angles to the flow of the river. Also called a diagonal wave or reaction wave.

 
 
 
 

 
scouting trail  The trail along the edge of most major rapids gives you a chance to look things over before entering a rapid.

 
 
 
 

 
sleeper  A rock hidden below the surface with enough water flowing over it to hide it, but maybe not enough for a boat to pass safely over it.

 
 
 
 

 
strainer  When large trees or other debris fall into the river, they form extremely dangerous obstacles not marked on the map. The water can pass through, but boats can’t.

 
 
 
 

 
surge  The sudden upswell of water caused by currents swirling around an obstacle hidden deep in the river. Also called a boil.

 
 
 
 

 
tongue  This slick, glossy V of quiet water between two obstacles marks the entrance to a rapid. The tongue is often the path that boaters follow to enter a rapid, because the water there is usually free of obstacles. Also known as a chute or slot.

 
 
 
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