Tuesday, August 28, 2007

A Glossary of Whitewater Terminology

We have been asked multiple times by guests to produce a glossary of common whitewater terms so that paddlers can communicate more effectively and understand the sport better. The beauty of having an online glossary is that we can add terminology as the sport grows and link to more detailed explanations of the terms with video and pictures as this blog grows in content. We plan on adding more terms to this post as we get time,

A Glossary

Awareness- having a broader scope of vision that encompasses not just one self but the surroundings and other paddlers on the river. See our previous post on river awareness.

Back Face – the convex side of the paddle blade

Back Ferry- going from one side of the river to the other without moving downsteam as in a ferry but in this case with the bow facing down stream. A "backferry" can also be used to maintain a stationary position in the the river, as the bow faces downstream this allows the paddler to look at what is coming up.

Backband – An adjustable brace that provides support in the lower lumbar region that encourages a neutral to aggressive posture. Helps encourage a better posture by rolling the hips forward.

Beatdown-If you have to ask, you have not seen one and definitely not experienced one. A beatdown typically describes any situation when the river exerts supreme power over puny paddlers. This is usually accomplished through large hydraulics but can apply to many situations when thing do not go according to plan. Examples include getting pinned, randomly flipped, trashed in holes, dragged over rocks and other events of such nature. River Gnomes are usually the instruments of beatdowns though they recent these duties.

Belay- In climbing refers to when a rope is used to prevent or arrest a fall. In paddling it can be used to lower boats, gear or a paddler in a controlled fashion down river.

Big Water-usually refers to rivers that are flooding or that have large volumes of water that produce very large river features. Typically flows in excess of 5000cfs are considered Big Water.

Blade – The end of a paddle (either canoe or kayak) that provides the "catch" in a paddle stroke. The Blade has a back face (convex) and power face (concave). Blade shapes for kayak paddles are typically asymmetrical or symmetrical, though most modern blade shapes are asymmetrical. Asymmetrical blades catch the water near the end of the blade early in stroke placement, whereas symmetrical catches along the entire length of the blade throughout the entire stroke. Canoe paddles are symmetrical and utilize only one blade with a t-grip on an opposing end.

Blunt-see our previous post on the Blunt

Boat Angle- boat angle is the angle, as viewed from above, between the imaginary line formed between the bow and stern of the boat, and the primary direction of the current flow of the river. Boat angle is sometimes designated by numbers (one o'clock) but more often in less precise terms (slight left boat angle, or strong boat angle). Two boats can be following the same line of travel but have completely different boat angles.

Boil- this is a water feature created when water churns upward and creates an elevated region in the river. In big water a boils can elevate and move kayaks several feet in random directions.

Boil Line- this is the line that delineates the water going down stream from the water that is flowing back toward a hydraulic. The further downstream a boil line is from the hydraulic, the more hazardous the feature.

Boof- a boof is a maneuver where a kayaker uses his paddle, rock or water feature to lift the bow of the kayak over a drop, usually performed to avoid a piton or getting stuck in a hydraulic. There are many reasons to perform a boof and this maneuver is the staple of advanced kayaking. See our earlier post on Boofing

Bow – The front of the kayak

Bow Draw- a correction stroke used to pull the front of the kayak or canoe to the side toward the paddle blade.

Bracing: Any paddle stroke that helps the paddler maintain his/her balance. The high and low brace are the most common bracing strokes but forward and turning strokes also work as bracing strokes in many situations.

High Brace - in a high brace the paddle is positioned perpendicular to the kayak, the power face is facing the water and the elbows are positioned bellow the hands.

Low Brace -in a low brace the paddle is positioned perpendicular to the kayak or canoe, the backside of the blade is facing the water and the elbows are positioned above the hands.

Bulkhead Brace – A plate mounted by aluminum bars in the hull that your feet rest on to help provide desired leverage and posture in the kayak

C to C Roll-A roll technique that has the paddler extend the paddle out perpendicular to the boat. The C to C describes the curled body position when the hip snap is executed and when the roll is finished. The first C (turn this C on its side so it looks like a U) is when the paddler extends his body upwards underwater from the side of the boat . The second C refers to the shape of the body in the finished position when the boat is upright.

C-1 – Single-person closed deck canoe

C-2 – Two-person closed deck canoe

Carabiner – an oval metal ring with a spring gate; typically used in mountaineering but used in river rescue as well

Catch- the first part of any paddle stroke is referred to the catch, a properly executed catch seats the blade in the water effectively and will have minimal aeration when the stroke is executed.

Channel- a division in the river, stream or flow that can created by an island, set of rocks or river feature.

Clean- executing a play boating move without using the paddle.

Cockpit-the area of the kayak where one gets into and out of the kayak. The size of the cockpit can vary depending on manufacturer.

Compound Stroke- when two or more different paddle strokes are executed in successions

Control Hand- refers to the hand that controls the angle of the paddle blade. For example in a "right hand control paddle," the right hand controls the angle or twist of the left blade. Hence you have to twist the right hand back to get the left blade perpendicular to the water.

Correction Stroke- any paddle stroke taken to adjust the angle or veer of the kayak, any number of different strokes can be used as corrective strokes: forward sweeps, back sweeps, forward strokes, bow draw, side draw, stern draw,

Deflection Current- the deflection current is one component of eddy lines. Technically this is the current that is flowing off either side of the rock or other obstacle in the stream. This current is typically faster than the current in the middle of the river, hence when a kayak approaches this current there is a greater deflection force toward downstream.

Displacement Hull- a displacement hull describes a kayak or canoe with a rounded bottom with no defined edge on the hull.

Downstream- direction of the current.

Downstream “V”- describes the shape of the current when it passes between two obstacles. The V points downstream and could be further delineated by wave trains.

Eddy- a river feature formed by an obstacle in the downstream flow. A well formed eddy will have a defined eddy line and a calm pool behind the obstacle. Being able to "catch" or stop in these calm pools is one of the keystones of whitewater paddling.

Eddy Fence-this very powerful eddy line feature lives in large volume or fast flowing rivers. The "fence" describes the area of the eddy line very close to the obstacle creating it, that is raised from the eddy pool. On the Grand Canyon River in Colorado there exists an eddy fence that can be two to three feet higher than the eddy pool. Usually an eddy with an "eddy fence" can very diffilcult to get out of.

Eddy Hopping-describes a boating style in which a kayaker works his way downriver or down an individual rapid by catching eddies. The paddler uses these eddies to scout, to set up moves, and to break up long stretches of whitewater into manageable segments.

Eddy Line-delineates the downstream flow of water from the upstream flow found in an eddy behind an obstruction. Eddy lines in faster water or created by above-water obstructions tend to be narrow and more well defined than those in slower water or those created by underwater obstructions. Eddy lines in slower water or created by underwater obstructions or by the banks of the river tend to be wider and "muddy" or unclear.

Eddy Turn-the act of catching an eddy. When a paddler crosses the eddy line the turn within the eddy is aptly named the eddy turn.

Ender-usually considerd an "old school" playboating move, though sometimes done by accident. Can be done on the stern or the bow, more often when done on the stern it is by accident. An ender is done when a paddler get's a vertical ejection from a hole, when done with grace the paddler will stand on their foot bracing system with the paddle high in the air and a grin from ear to ear. This move is best done in a boat with length.

Feather-refers to the off-set of your paddle blades, most common is a 45 degree although paddlers now are using a wide variety of feather now. It can also refer to feathering your blade in the water, which are minor adjustments you might make on your blade while it is still in the water to make a more effective stroke.

Ferry-the act of crossing a section of river without going downstream. While usually thought of as crossing the entire river, a ferry may simply involve moving out into the current a certain distance before allowing the boat to move downstream.

Flotation- inflatable airbags that displace water in swamped boats, usually placed in the rear of the kayak, canoes usually have bow and stern flotation.

Foam Pile- foam pile is usually reserved for the white frothy water washing back into a hole.

Forward Stroke-while the kayaker may be able to move his boat in a straight line with a wide range of paddle maneuvers, the Forward Stroke may best be thought of as an efficient way of accelerating the kayak in a direct path. Efficient acceleration or forward strokes tend to be close to the boat with a vertical or nearly vertical paddle shaft. Powerful strokes enter the water far towards the front of the boat, at or past the toes, with the entire paddle blade anchored firmly in the water. Unless linked to another stroke (such as a stern draw), recovery takes place somewhere between the knees and the hips. The paddler may consider that a firm and constant "grip" or anchor in the water with the paddle lends much more power than simply focusing on a fast stroke rate. As with any strokes, many variables come into play to affect actual execution: water depth, obstructions, speed required, and necessity of linking or combining strokes. However, all strokes can gain efficiency if the paddler focuses on engaging core muscles to move the boat itslelf rather than just moving the paddle.

Freestyle-the commonly used name for modern playboating.

Gauge-measures river volume in feet (physical height of the water in the river), cubic feet per second (CFS) which is the amount of water passing that particular spot on the river. A visual representation of this is to imagine that the water in the river is made up of basketballs thus the CFS in this case would be the number of basketballs passing a given spot in a second. A higher CFS means more water in the river. Can also be measured in meters per second (MTS).

Gradient- the amount of vertical feet a river drops over the course of its length. Rivers that loose a lot of vertical feet in a short distance are said to have a steep Gradient.

Grab Loop-loops placed in the front and back of the kayak typically used to carry the boat or tie it down to a vehicle. Grab loops can also be utilized to rescue swimmers by giving them a place to hold onto while you tow them to shore.

Green Wave-a wave feature that does not break at the top.

Horizon Line- when looking downstream this is a line where the river drops off. The steeper the vertical drop, the less visible the bottom of the drop will be. This is the proverbial waterfall line.

Hull- the bottom side of the kayak

Hydraulic- also known as a hole, is a river feature where water drops over a obstruction (rock ledge or a rock) into deeper water on the downstream side. This causes water on the surface to be drawn back toward the rock or ledge. This can be a potentially hazardous feature but it could aslo be a feature used for playboating. Low head dam's are the most dangerous example of a hydraulic.

J-lean-A way to tilt a kayak by keeping the head centered and raising one knee while slightly shifting bodyweight slightly to one side. A properly executed J-lean allows the kayak to be tilted without losing stability and balance.

K-I- a solo kayak

Line-a path through a rapid

Low Brace Roll: this is the roll used to right an open boat.

OC-2-Open canoe for 2 people, also known as a tandem canoe

Offside-In rolling, offside usually refers to a roll in which the kayaker initiates the paddle sweep with the left hand. The setup position puts the left hand at the right foot and the right hand near the right hip. Offside can also refer to a roll in which the kayaker initiates the paddle sweep with the non-dominant hand. Outside the context of rolling, offside may be used to refer to a paddler's weaker side.

Onside- In rolling, onside usually refers to a roll in which the kayaker initiates the paddle sweep with the right hand. The setup position puts the right hand at the left foot and the left hand near the left hip. Onside can also refer to a roll in which the paddler initiates the paddle sweep with the dominant hand. Outside the context of rolling, onside may be used to refer to a paddler's stronger side. Canoeist also have an onside and offside.

Outfitting - outfitting can be the factory pieces that came with your boat; seat, thigh hooks, foot brace, backband. It can also be custom fit pieces of foam you have placed in the boat to make it fit you.

Peel Out- the act of leaving an eddy and entering the current. A paddler exits the eddy with an angle slightly toward the current, paddling until the boat is fully into the current then leans to the inside of the turn until the boat is pointed downstream.

PFD- Personal Flotation Device, also known as a life jacket.

Pillow - is the water that builds up on the upstream side of an obstruction.

Pivot Turn- a pivot turn is a quick turn done on the stern of the kayak when a paddler drops one edge of the boat and performs a back sweep on the opposite side of the boat. This turn is done most often in slalom kayaking.

Planing Hull- is the flat bottom design of most modern day kayaks.

Playboating- a type of kayaking where kayakers get onto a river feature such as a wave or hole and perform tricks. It can also be done while going downriver using a varity of river features. Also referred to as freestyle kayaking.

Pool- a section of river that is calm in between or after a rapid.

Portage- the act of walking around a rapid because it is not safe to run. Sometimes mandatory and sometimes by a paddlers personal discretion.

Pothole- a geological feature on a river where water has eroded out a hole in a rock.

Pour Over - when water goes over an obstacle like a ledge or other feature. Large steep pour overs or will generally have a hydraulic on the downstream side.

Power Face- the scooped side of the paddle blade.

Power Ferry - also called a "jet ferry" is a ferry done in very fast moving, irregular water.

Pulley- a pulley is a simple mechanical device that is used sometimes in a kayakers "pin kit". A pulley will give a rescuer a mechanical advantage when trying to free a pinned boat.

Recovery- regaining control after after running a rapid. It could also be the act of regaining control after performing a roll or another manuver such as a freestyle move.

River Etiquette: is the curtsey and respect shown to other paddlers on the river. Basic River etiquette says that paddlers with Down Stream momentum or paddlers going downstream have the right away. This means that if you are in an eddy you must look upstream before pulling out to avoid possibly getting in some paddlers way. These rules are largely un written but are essential to regulating traffic on the river. This is also related to River Awareness.

River left- the orientation of the bank in relation to the downstream current.

River ratings-

Class I: Easy. Fast moving water with riffles and small waves. Few obstructions, all obvious and easily missed with little training. Risk to swimmers is slight; self-rescue is easy.

Class II: Novice. Straightforward rapids with wide, clear channels which are evident without scouting. Occasional maneuvering may be required, but rocks and medium- sized waves are easily missed by trained paddlers. Swimmers are seldom injured and group assistance, while helpful, is seldom needed. Rapids that are at the upper end of this difficulty range are designated "Class II+".

Class III: Intermediate. Rapids with moderate, irregular waves which may be difficult to avoid and which can swamp an open canoe. Complex maneuvers in fast current and good boat control in tight passages or around ledges are often required; large waves or strainers may be present but are easily avoided. Strong eddies and powerful current effects can be found, particularly on large-volume rivers. scouting is advisable for inexperienced parties. Injuries while swimming are rare; self-rescue is usually easy but group assistance may be required to avoid long swims. Rapids that are at the lower or upper end of this difficulty range are designated "Class III-" or "Class III+" respectively.

Class IV: Advanced. Intense, powerful but predictable rapids requiring precise boat handling in turbulent water. Depending on the character of the river, it may feature large, unavoidable waves and holes or constricted passages demanding fast maneuvers under pressure. A fast, reliable eddy turn may be needed to initiate maneuvers, scout rapids, or rest. Rapids may require "must" moves above dangerous hazards. Scouting may be necessary the first time down. Risk of injury to swimmers is moderate to high, and water conditions may make self-rescue difficult. Group assistance for rescue is often essential but requires practiced skills. A strong eskimo roll is highly recommended. Rapids that are at the upper end of this difficulty range are designated "Class IV-" or "Class IV+" respectively.

Class 5: Expert. Extremely long, obstructed, or very violent rapids which expose a paddler to added risk. Drops may contain large, unavoidable waves and holes or steep, congested chutes with complex, demanding routes. Rapids may continue for long distances between pools, demanding a high level of fitness. What eddies exist may be small, turbulent, or difficult to reach. At the high end of the scale, several of these factors may be combined. Scouting is recommended but may be difficult. Swims are dangerous, and rescue is often difficult even for experts. A very reliable eskimo roll, proper equipment, extensive experience, and practiced rescue skills are essential. Because of the large range of difficulty that exists beyond Class IV, Class 5 is an open-ended, multiple-level scale designated by class 5.0, 5.1, 5.2, etc... each of these levels is an order of magnitude more difficult than the last. Example: increasing difficulty from Class 5.0 to Class 5.1 is a similar order of magnitude as increasing from Class IV to Class 5.0.

Class VI: Extreme and Exploratory. These runs have almost never been attempted and often exemplify the extremes of difficulty, unpredictability and danger. The consequences of errors are very severe and rescue may be impossible. For teams of experts only, at favorable water levels, after close personal inspection and taking all precautions. After a Class VI rapids has been run many times, its rating may be changed to an appropriate Class 5.x rating.

River Right- the oreintation of the bank in relation to the downstream current.

River Signals- a set of designated signals that gives paddlers a the ability to comminicate at a distance while on the river.

Rock Garden: usually describes a rapid with many, many boulders. Usually good for eddy hopping but bad for swimming.

Roll- a maneuver that will right a kayak after it has been turned upside down. There are many types of rolls, most of which were developed for sea kayaking, (see Greenland Rolls) The most common rolls used in whitewater kayaking are the C to C, the Sweep Roll, Hands Roll and the Back Deck Roll. The open boat or canoe roll is typically done with a Low Brace Roll.

Scout- the act of looking ahead at a rapid either in the boat or on foot to find the line.

Self Rescue: when a paddler swims and gets him/herself to shore with or without their boat and gear, it is called a self rescue.

Shaft- the area of the paddle in between blades on a kayak paddle, and between the t-grip and the blade on a canoe paddle.

Shore- the bank of the river.

Sidewall- this term refers the side of the kayak between the deck and the hull.

Sieve- a very dangerous feature on the river usually caused by two rocks where water passes through, but a boat or paddler my not pass through.

•Slalom- a type of kayak and canoe racing where paddlers must pass through a series of designated upstream and downstream gates in a timed format. Slalom is currently the only kayakink event in the olympic games.

Spin- could refer to a playboating move where a paddler does a 360 degree turn on a wave or in a hole. Also could refer to how a boat reacts when a paddler uses a wide sweeping stroke.

•Spray Skirt- the neoprene deck that a paddler wears on their waist that attaches to the cockpit rim of the kayak in order to keep water out of the boat.

Squirt Boat- a specially designed boat for a specific type of kayaking where paddlers do manuvers such as "mystery moves" a manuver where the paddler travels below the surface of the river into the narthex.

Stern- the back of a whitewater kayak.

Stern Draw- a stroke in which a paddler uses a wide sweeping stroke placed into the water at the hip then sweeps water toward the stern of the boat. A very effective stroke for quick turns when done correctly.

Suckhole- a very powerful hydraulic.

Surf- a surf is a manuver in which a paddler stays on a wave or in a hole. Can be done on purpose or by accident.

•Sweep Roll- in a sweep roll the paddler rolls the kayak while the paddle sweeps an arc on the surface of the water.

Sweep Stroke-a wide arcing stroke that when done correctly is very effective for initiating turns.

Take Out – Where the river-journey ends.

T-Draw – a stroke utilized to move the boat sideways. The blade is planted with a vertical paddle shaft and power face directing torwards the side of the boat and pulled torwards the boat. The blade is then turned, power face facing stern, and sliced back out to the original position.

Throat – Where the paddle blade and shaft meet on a kayak paddle.

Throw Bag – A rope made out of either poly or spectra rope that is flaked into a stuff sack that makes it easily stored.

Throw Rope – A rope coil made out of a high flotation rope preferred by raft guides for its ease to throw and recoil quickly

Trim – How a boat sits in the water based upon where the paddlers weight is focused. A balanced trim would be if the bow and stern are the equidistant in the water.

Undercut Rock – A rock with a void on the underside. There are many types of undercuts varying in danger. The most dangerous of these being an undercut with an upstream face having a void and the flow leading into it.

Upstream – Where the flow comes from

Upstream “V” – found on either side of a downstream “V” which represents the shape an eddy makes. Obstacles on both right and left will create downstream “V’s” and those obstacles create eddies.

Veer – A kayaks natural tendency to want to turn, this due in large part to a kayaks length, width, rocker and shape of hull. Hence, a long narrow boat with very little rocker has less veer i.e. sea kayak. The shorter fatter boats with lots of rocker veer much more i.e. creek boat.

Wave Hole – A wave that has a breaking foam pile

Standing Waves – or wave trains are associated with constricted areas of water most commonly called Downstream V’s. Water can only be pushed out downstream so fast so the water pushes upward into waves.

Wet Exit – The most fundamental skill of self rescue. The Wet-Exit includes four basic steps in case of a capsize, this would include tucking forward onto the deck of the kayak, tapping on the hull of the boat to call attention, pulling the skirt off the cockpit and pushing yourself out of the boat while staying in a tucked and safe position.

Wildwater – A discipline of downriver racing which utilizes a specialized assymetrical kayak typically made of a composite material.

Z-Drag – A mechanical advantage system involving carabiners, rope, prussiks, and pulleys to aid in removal of a pinned object. A typical Z-drag gives a 3:1 ratio, meaning for every pound you enter the system it multiplies the force by 3. For a more detailed description and its practical uses reference River Rescue by Slim Ray and Les Bechdel. See our previous post on the Z Drag.


Anonymous said...

Where you bored?

Port said...

We have been asked several times by people on the Boatertalk Skills Development page and by our NOC guests to produce a glossary directed at helping new boaters out. Hope it helps.

Heliyaker said...

Very resourceful, in typical NOC fashion. Look forward public feedback on the 45 vs 0 study. Of course a 45 to 30 to 12, self study has gotten more neg than pos., reaction myself. Thinking about a stern-draw toward the start line @ 45, to self-check my own trial and error. Will stay tuned.

Anonymous said...

Good job! One nit to pick is your equating a hole and a hydraulic. I prefer to characterize a hole as having a distinct depression downstream of the obstruction with water continuing to flow downstream, often followed by a series of standing waves. What you are calling a "wave hole" (a hole as I have described it with a breaking wave downstreeam) is what has traditionally been called a "stopper." I restrict the term hydraulic to pour-overs with a recirculating pattern that can be recognized by a crease (vs. a depression), a foamy backwash and a boil line. This seems to help instructors and their beginning students understand the difference.

Bruce Williams
(ACA Whitewater Kayak Instructor Trainer)