River Terms

Paddlers' Terminology 101

Broach
Occurs when a canoe or kayak becomes caught up against an obstacle and turned sideways to the current. Can result in severe damage as the current's force warps the boat around the obstruction.
CFS
Cubic Feet per Second. Measurement of velocity of water flow at a given point in a river. Will vary according to water level and gradient of riverbed.
Drop
A short, well-defined rapid, or section of a rapid. Named for the abrupt 'drop' in elevation between the top and bottom.
Eddy
Area of usually calm water behind or downstream of an obstruction in the main current, where water flows counter to that of the main current.
FIB or FISH
A highly technical term often used by Wisconsin paddle instructors and rafting guides to describe a client who whines and complains.
FPM
Feet per Mile - In this guide this is used as an average for gradient, or an average of elevation drop in feet over a distance of a mile. In most cases, the higher the number, the greater the difficulty of the river in that section. For example, a gradient of 30.0 fpm or more will likely indicate a fast current and difficult rapids, whereas a gradient of 4.5 fpm would likely indicate a slower current and calm waters. It should be noted that this is not always an accurate indicator of a rivers' difficulty!
Fork
A Fork is where the river splits into at least two different channels.
Haystacks
A series of standing waves or runout of a rapid.
Highside
When you broach on a rock with a raft, everyone moves to the highside to push it back down so it won't wrap around the rock.
Hole
A hole is created when the river current drops over a rock or ledge and circulates instead of continues its downstream flow. This is a significant feature because it offers both play opportunities, or danger of trapping, depending on the power of the hole. Avoid swimming in a hole, you will likely be sucked underwater.
Horizon line
Usually indicates: a falls, ledge, steep drop, or a dam. There is a visible line that runs across the river, usually with a calm area of water just above it. The route, if there is one, is not apparent. Time to exit and scout.
Hydraulic
Water formation that often occurs after or just below: a sudden drop in the riverbed, or a sudden drop over an obstruction such as a submerged boulder. The hydraulic is the powerful circulating force at the base of the drop. The circulating pressure of a powerful hydraulic can hold boats and swimmers for indeterminate lengths of time.
Hypothermia
The cold water hazard for paddlers. Prolonged exposure can lead to incapacitation and eventually death as body core temperature drops below 80 degrees.
Ledge
Ledges are submerged rock shelves which the river flows over forming a drop. River-wide ledges are common on Wisconsin Rivers. A horizon line is a dead giveaway that you are approaching one, and you should always land and scout if you are not sure you can safely navigate over it.
PFD
Personal Floating Device. The proper name for a Life Jacket, or Vest, per Coast Guard definition. It is required by law for every passenger of all water craft and your most important life-saving tool.
Pin
Refers to a situation where your canoe or raft becomes stuck or lodges against an obstacle, such as a boulder(s), in a perpendicular position to the current. This is potentially one of the most dangerous situations for paddlers.
Portage
Term for carrying boats and gear around a difficult rapid, dam, or river-wide obstruction, or from lake to lake.
Put-in
Starting place of a river trip; where you put your boat on the river to begin a run or trip.
River Gage
For measuring water levels (height) at one or more locations. Reference point used with CFS (or in lieu of).
River Left
The left-hand side of the river when looking downstream. When downstream looking upstream it is on your right.
River Right
The right-hand side of the river when looking downstream. When downstream looking upstream it is on your left.
Shuttle
Driving between the put-in and take-out. One-vehicle shuttles require logistical foresight using options such as biking, walking, hitchhiking, etc., to return to the put-in.
Standing Waves
Big waves that often indicate the main channel. Large standing waves can be dangerous, especially for canoes.
Strainer
Where overhanging tree branches or debris are partially submerged in the current and allows the water to flow through it. This will likely pin you or your boat. Very Dangerous!
Take-out
The ending point of a paddling trip, where the boats are finally taken from the water.
Waterfall
A major drop in a riverbed, usually over five feet in height.
Wave Train
A series of standing waves or runout of a rapid. Also called "Haystacks".
Wrap
To wrap your canoe or raft around a rock or obstacle. Countered by leaning into the rock or highsiding a raft.