River Rafting Sport - An Introduction

A Paper on River Rafting Sport

Rafting or whitewater rafting is a challenging recreational activity utilizing a raft to navigate a river or other bodies of water. This is usually done on whitewater or different degrees of rough water, in order to thrill and excite the raft passengers. The development of this activity as a leisure sport has become popular since the mid 1970s.

Classification of whitewater

The most widely used grading system is the International Grading System where whitewater (either an individual rapid, or the entire river) is classed in six categories from class I (the easiest and safest) to class VI (the most difficult and most dangerous). The grade reflects both the technical difficulty and the danger associated with a rapid, with grade I referring to flat or slow moving water with few hazards, and grade VI referring to the hardest rapids which are very dangerous even for expert paddlers, and are rarely run. Grade-VI rapids are sometimes downgraded to grade-V or V+ if they have been run successfully. Harder rapids (for example a grade-V rapid on a mainly grade-III river) are often portaged, a French term for carrying. A portaged rapid is where the boater lands and carries the boat around the hazard.
A rapid's grade is not fixed, since it may vary greatly depending on the water depth and speed of flow. Although some rapids may be easier at high flows because features are covered or "washed-out," high water usually makes rapids more difficult and dangerous. At flood stage, even rapids which are usually easy can contain lethal and unpredictable hazards.

Class 1: Very small rough areas, requires no maneuvering. (Skill Level: None)

Class 2: Some rough water, maybe some rocks, small drops, might require maneuvering. (Skill Level: Basic Paddling Skill)

Class 3: Whitewater, medium waves, maybe a 3-5 ft drop, but not much considerable danger. May require significant maneuvering. (Skill Level: Experienced paddling skills)

Class 4: Whitewater, large waves, rocks, maybe a considerable drop, sharp maneuvers may be needed. (Skill Level: Whitewater Experience)

Class 5: Whitewater, large waves, large rocks and hazards, maybe a large drop, precise maneuvering (Skill Level: Advanced Whitewater Experience)

Class 6: Whitewater, typically with huge waves, huge rocks and hazards, huge drops, but sometimes labeled thusly due to largely invisible dangers (i.e., a smooth slide that creates a near-perfect, almost inescapable hydraulic, as at Woodall Shoals/Chattooga). Class 6 rapids are considered hazardous even for expert paddlers using state-of-the-art equipment, and come with the warning "danger to life or limb." (Skill Level: Expert)

Whitewater rafts

Rafts were originally the simplest form of man’s transportation in water and were then made of several logs, planks or reeds which were fastened together. Nowadays, inflatable were used as rafts which were later adopted by the military for beach assaults. It consists of very durable, multi-layered rubberized or vinyl fabrics with several independent air chambers. Its length varies between 3.5 m (11 ft) and 6 m (20 ft), the width between 1.8 m (6 ft) and 2.5 m (8 ft). The exception to this size rule is usually the packraft, which is designed as a portable single-person raft and may be as small as 1.5m long and weigh as little as 4 lbs.
Rafts come in a few different forms. In Europe the most common is the symmetrical raft steered with a paddle at the stern. Other types are the asymmetrical, rudder-controlled raft and the symmetrical raft with central helm oars. Rafts are usually propelled with ordinary paddles and typically hold 4 to 12 persons. In Russia rafts are often hand made and are often a catamaran style with two inflatable tubes attached to a frame. Pairs of paddlers navigate these rafts. Catamaran style rafts have become popular in the western United States as well, but are typically rowed instead of paddled.

Rivers with high current is used for White water rafting. Specially, White Water Rafting is popular in Himalayas due to high current of water falling through hills and rocky mountains.

HOW TO HANDLE YOUR RAFT IN THE WHITE WATER

HOW DO WE GET ALL OF THIS TO WORK TOGETHER?

If you are interested in some of the tips and tricks to properly navigate your boat down the river, take a few minutes to read some of the things that we teach you just before you get on the river. This is not a complete instruction, but you'll get some goodies here that you'll want to hear a bit more about before you take off for your first run.

THE BASICS TO GET STARTED

Well, part of the fun is figuring it out for yourself, but if you are going to get your feet wet, and want to know a bit more about it, here it is.

First you decide on what type of trip: Guided, Group Guide Assisted, or Rental.

Then you choose the length of the trip you would like to try. Usually a full river.

Then you select your boat size and style based on the size of your group.

Then you are ready to go, right? Not yet anyway.

When you get your boat, and you are ready to pile in and make a go of it, there are a few things to consider. The most important is how to position your paddlers. Consider weight and paddling strength as your primary factors. You want to balance the weight and paddling power, so when you call "All Forward", you go straight, and not left or right. It will be up to the guide, or the boat captain to steer the boat, so if you are fighting an unbalanced boat, its going to make you do a bit of additional work if you are going to keep the boat straight.

You as a guide can use your paddle behind your hip like a rudder on a sail boat. Holding the blade back and forth in the water to move the rear of the boat. When you move the rear of the boat, the front is going to angle also. Remember, it is best to steer the boat, or change it's direction when the boat is moving, but not under full power. You call "All Forward", and the boat begins to move forward. You make wide sweeps with your paddle from behind the boat to the side, and from the side of the boat to the rear of the boat when you need to make solid corrections. Minor adjustments can be made using the rudder technique. It is more effective to yell, "All Rest", and make your correction strokes, then "All Forward Again". If you need to slow down, you can call "All Back", and everyone will back paddle to slow you down.

If you really need to turn fast or you want to spin while paddling through some curling waves, you can call "Right Back, and Left Forward", or you can use the reverse to get the other side of the boat wet.

The basic idea of navigating the river is "Turn the Boat, Paddle Forward, then Turn the Boat and Paddle Forward". When you are paddling, and you look ahead and see a big rock, you need to get back to the basics. Turn the Boat, paddle forward far enough to clear the rock, then turn the boat back straight, and either rest, or paddle forward. Practice fine tuning your steering, because you never know when you will need to make that precise adjustment.

WE ARE STUCK ON A ROCK, NOW WHAT DO WE DO?

Well, you can wait until the river goes down, and then get out and carry your raft to the bank! . Or you can helplessly jump up and down in the boat and yell at everyone else for not being in sync with you. Or maybe you pump out a few wise cracks about that extra biscuit you ate this morning. Or you can listen to all of the other rafters passing by that think they have a solution for you. Or maybe some friendly river guide will be passing by and give you a bump. If all of that doesn't work, then you must be really stuck, and might need a bit more ideas. Well, here they are! Remember that there are two major factors here to consider. One is the weight of the passengers in the craft (not the biggest factor), the other is the location of the rock that is holding you, and last but not least, the water factor. This will work in just about every situation you find yourself in except for the fact that you just floated into the Raft

Cradle or the Raft Trap

Find the location of the rock that has a hold of the bottom of your raft. Move the largest amount of the weight to the other end of the raft. Lean way out of the raft, away from the rock, and use your paddles against the strongest part of the curent to pull you off of the rock. Try to twirl it off of the rock.

Don't fight the water, it always wins. Use the water to help you lift the side of the boat. If you can slowly lift one side of the boat, just enough that you can get a flow of water back under the boat, you can break the suction on the rock and usually break free. Prior to your rafting trip, we will tell you about undercut rocks and foot entrapments. Pay very close attention. These are very real dangers.

If that doesn't work, someone always ends up getting out of the raft, and giving it a shove or two. Just remember, the rocks are slippery. If you are going to get out of your boat despite the dangers, do it on the up river side of the raft. Never take your hands off of the raft, and always try to keep your torso over the side of the raft. If you slip, you'll bounce on the raft, and save an unexpected dip in the water. Just remember that foot entrapments are real and you should keep your foot movement to an absolute minimum.

The best option is to wait a few more minutes. There will generally be another boat behind you with a qualified guide to give you a bump, or shove, or even get out of his craft and get you off of the rock.

I FELL OUT OF THE BOAT, NOW WHAT?

Well, we will show you the recommended swim position for the river. Lay on your back, feet downstream, and float to safety. Push off of any rocks that might get in your way, and use your arms to paddle to safety. Personally, I turn over on my stomach, and swim back to the raft. What happens if you cannot swim back to your raft? Well, you'll have to swim to the bank, unless you want to do a bit more floating. Just remember, don't stand up until you can sit on the bottom of the river keeping your head above water, or you can do a pushup on the floor of the river and still keep your head well above the water. Foot entrapment or not, you'll be Ok. Hang on to your paddle, it might be the last couple of extra inches that you need to get someone in the boat to pull you back close enough that you can get back in. You can always find your raft, and your buddies. But will they let you back in the boat if you have lost your paddle? We'll tell you how to help a passenger back in the raft using the life jacket as handles. I know what you're thinking. How in the world can I get him back in the raft? I can't pick him up! We'll also tell you a little secret about that too. Just remember what a cork does when it is shoved under the water. On the count of three, just a little shove down into the water makes the feet really start kicking, and they'll pop right out of the water like a cork. This really works good on Dad's when they fall out!

Don't you tell him I told you to do that!!

If you happen to get tossed out of the boat at the end of your run, amidst all of the excitement, you might hear someone yell "ROPE"! That's your cue that help is on it's way. Many people enjoy setting up at the falls to catch what we call "River Carnage". When you hear "ROPE", look up and reach! Someone is throwing you a rope. Just grab onto the rope, pull your hands in close to your chest, route the rope over your shoulder, lay on your back, and hang on. The rope, current, and your weight all work together to quickly swing you to the bank of the river. A quick smile, and a big "thanks" are really appreciated by the rope throwers. Don't forget, Pat King just took your picture at the falls. Those pictures are the ones you really want to hang on the wall.

They'll be talking about them for years to come.

These are some of the things that you'll get in our safety briefing and river instructional, and we make it fun! We cover all aspects of Safety, and try to cover the most likely situations that you might experience while on the river.
The more you know, the more comfortable you will be, and the more you will enjoy the wonderful sport of White Water River Rafting.

About Whitewater

Whitewater is formed in a rapid, when a river’s gradient drops enough to disturb its laminar flow and create turbulence, e.g. form a bubbly, or aerated and unstable current; the frothy water appears white. The term is also used loosely to refer to less-turbulent but still agitated flows.
The term "whitewater" also has a broader meaning, applying to any river or creek itself that has a significant number of rapids. The term is also used as an adjective describing boating on such rivers, such as whitewater kayaking.

Rapids

Four factors, separately or in combination, can create rapids: gradient, constriction, obstruction and flow rate. Gradient, constriction and obstruction are streambed topography factors and are relatively consistent. Flow rate is dependent upon both seasonal variation in precipitation and snowmelt and upon release rates of upstream dams.
Streambed topography
Streambed topography is the primary factor in creating rapids, and is generally consistent over time. Increased flow, as during a flood or high rainfall season can make permanent changes to the streambed by displacing rocks and boulders, by deposition of alluvium or by creating new channels for flowing water.

Gradient

The gradient of a river is the rate at which it loses elevation along its course. This loss determines the river's slope, and to a large extent its rate of flow. Shallow gradients produce gentle, slow rivers while steep gradients are associated with raging torrents.
Constriction
Constriction can form a rapid when a river's flow is forced into a narrower channel. This pressure causes the water to flow more rapidly (hence the name) and to react differently to riverbed events (rocks, drops, etc.)

Obstruction

A boulder or ledge in the middle of a river or near the side can obstruct the flow of the river, and can also create a "cushion"; a "drop" (over the boulder); and "hydraulics" or "holes" where the river flows back on itself--perhaps back under the drop--often with fearful results for those caught in its grasp. (Holes, or hydraulics, are so-called because their foamy, aerated water provides less buoyancy and can feel like an actual hole in the river surface.) If the flow passes next to the obstruction, an eddy may form behind the obstruction; although eddies are typically sheltered areas where boaters can stop to rest, scout or leave the main current, they may be swirling and whirlpool-like. As with hydraulics (which pull downward rather than to the side and are, essentially, eddies turned at a 90-degree angle), the power of eddies increases with the flow rate.

Stream flow rate

A marked increase or decrease in flow can create a rapid (where previously wasn't one), "wash out" a rapid (decreasing the hazard) or make safe passage through previously-navigable rapids more difficult or impossible. Flow rate is typically measured in cubic meters per second (cumecs), or in cubic feet per second (cfs), depending on the country.

Features found in whitewater

On any given rapid there can be a multitude of different features which arise from the interplay between the shape of the riverbed and the velocity of the water in the stream.

Strainers

Strainers are formed when an object blocks the passage of larger objects but allows the flow of water to continue - like a big food strainer or colander. These objects can be very dangerous, because the force of the water will pin an object or body against the strainer and then pile up, pushing it down under water. Strainers are formed by many different objects, like storm grates over tunnels, trees that have fallen into a river ("log jam"), bushes by the side of the river that are flooded during high water, or rebar from broken concrete structures in the water. In an emergency it is often best to try and climb on top of a strainer so as not to be pinned against the object under the water. If you are in a river, swimming aggressively away from the strainer and into the main channel is your best bet. If you cannot avoid the strainer, you should swim hard towards it and try to get as much of your body up and over it as possible.

Sweepers

Sweepers are trees fallen or heavily leaning over the river, still rooted on the shore and not fully submerged. Its trunk and branches may form an obstruction in the river like strainers. Since it is an obstruction from above, it often does not contribute to whitewater features but may create turbulence. In fast water sweepers can pose a serious hazard to paddlers.

Holes

Holes, or "hydraulics", (also known as "stoppers" or "souse-holes"), are formed when water pours over the top of a submerged object, causing the surface water to flow back upstream toward the object. Holes can be particularly dangerous—a boater may become stuck in the recirculating water—or entertaining playspots, where paddlers use the holes' features to perform various playboating moves. In high-volume water, holes dramatically aerate the water, possibly to the point where it may even lose the capacity to carry any water crafts.

Some of the most dangerous types of holes are formed by lowhead dams weirs, underwater ledges, and similar types of obstruction. In lowhead dams, the hole has a very symmetrical character - there's no weak point - and where the sides of the hydraulic are often blocked by a man-made wall, making it impossible to slip off the side of the hydraulic. Lowhead dams are insidiously dangerous because their danger cannot be easily recognized by people who have not studied whitewater.

Waves

Waves are formed in a similar nature to hydraulics and are sometimes also considered hydraulics as well. Waves are noted by the large smooth face on the water rushing down. Sometimes a particularly large wave will also be followed by a "wave train", a long series of waves. These standing waves can be smooth or, particularly the larger ones, can be breaking waves.

Because of the rough and random pattern of a riverbed, waves are often not perpendicular to the river's current. This makes them challenging for boaters since a strong sideways or diagonal wave can throw the craft off.

In fluid mechanics, waves are classified as laminar, but the whitewater world has also included waves with turbulence ("breaking waves") under the general heading of waves.

Pillows

Pillows are formed when a large flow of water runs into a large obstruction, causing water to "pile up" or "boil" against the face of the obstruction. Pillows can be dangerous because sometimes the object that forms the pillow is undercut and so paddlers can be swept underwater - possibly to be entrapped. Pillows are also known as "pressure waves".

Eddies

Eddies are formed, like hydraulics, on the downstream face of an obstruction. Unlike hydraulics, eddies swirl on the horizontal surface of the water. Typically, they are calm spots where the downward movement of water is partially or fully arrested - a nice place to rest or to make one's way upstream. However, in very powerful water, eddies can have powerful, swirling currents which can flip boats and from which escape can be very difficult.

Undercut rocks

Undercut rocks are rocks that have been worn down underneath the surface by the river. They can be extremely dangerous features of a rapid because a person can get trapped underneath them, under water. This is espcially true of rocks that are undercut on the upstream side. Here, a boater may become pinned against the rock underwater. Many whitewater deaths have occurred in this fashion. Undercuts sometimes have pillows, but other times the water just flows smoothly under them, which can indicate that the rock is undercut. Undercuts are most common in rivers where the riverbed cuts through sedimentary rocks like limestone rather than igneous rock like granite. In a steep canyon, the side walls of the canyon can also be undercut.
A particularly notorious undercut rock is Dimple Rock, in Dimple Rapid on the Lower Youghiogheny River in Pennsylvania. Nine people have died here, including three in 2000.

Sieves

Another major whitewater feature is a sieve, which is a narrow empty space that water flows through between two obstructions, usually rocks. Similar to strainers, water is forced through the sieve, resulting in higher pressures which forces water up and creates turbulencem


Whitewater Craft

A solo kayak paddler performs a high brace in foamy water. One of the hazards of whitewater paddling is that highly-aerated water decreases the effect of buoyancy.

There are many different types of whitewater craft that people use to make their way down a rapid, preferably with finesse and control. Here is a short list of them.

Whitewater Kayaks differ from sea kayaks and recreational kayaks in that they are specialized to deal with moving water better. They are often shorter and more maneuverable than sea kayaks and are specially designed to deal with water flowing up onto their decks. Most whitewater kayaks are made of plastics these days, although some paddlers (especially racers and "squirt boaters") use kayaks made of fiberglass composites. Whitewater kayaks are fairly stable in turbulent water, once the paddler is skillful with them; if flipped upside-down, the skilled paddler can easily roll them back upright. This essential skill of whitewater kayaking is called the “Eskimos Roll" or simply "Roll." Kayaks are paddled in a low sitting position (legs extended forward), with a two-bladed paddle.

Rafts are also often used as a whitewater craft; more stable than typical kayaks, they are less maneuverable. Rafts can carry large loads, so they are often used for expeditions. Typical whitewater rafts are inflatable craft, made from high strength fabric coated with PVC, Urethane, Neoprene or Hypalon. While most rafts are large multi-passenger craft, the smallest rafts are

single-person whitewater craft

Catarafts are constructed from the same materials as rafts. They can either be paddled or rowed with oars. A specialized cataraft, designed without any metal frame, is a Shredder. It was invented in 1982 by Tom Love is manufactured by his company Airtight Inflatables in Ohiopyle, Pa. A Shredder is specifically designed to be paddled. It is usually paddled by a two person crew, though highly skilled paddlers are able to negotiate extreme whitewater in a Shredder paddled as a solo boat. Typical catarafts are constructed from two inflatable pontoons on either side of the craft which are bridged by a frame. Oar propelled catarafts have the occupants sitting on seats mounted on the frame. Virtually all oar powered catarafts are operated by a boatsman with passengers having no direct responsibilities. Catarafts can be of all sizes. Many are smaller and more maneuverable than a typical raft.

Modern Whitewater Canoe

Canoes are often made of fiberglass, kevlar, plastic or a combination of the three for strength and durability. They may have a spraycover, resembling a kayak, or "open," resembling the typical canoe. This type of canoe is usually referred to simply as an "open boat." Whitewater canoes are paddled in a low kneeling position, with a one-bladed paddle. Open whitewater canoes have large airbags to prevent the boat from being swamped by big waves and holes. Like kayaks, whitewater canoes can be righted after capsizing with an Eskimo Roll, but requires more skill.
C1s are similar in construction to whitewater kayaks. However, they are paddled in a low, kneeling position. They employ the use of a one-blade paddle, usually a little shorter than used in a more traditional canoe. They will have a spraycover, essentially the same type used in kayaking. Like kayaks, whitewater canoes can be righted after capsizing with an Eskimo Roll.Mckenzie River Dory or "Drift Boat" by some. A more traditional "hard sided" boat. The design is characterized by a wide, flat bottom, flared sides, a narrow, flat bow, a pointed stern, and extreme rocker in the bow and stern to allow the boat to spin about its center for ease in maneuvering in rapids.

Have a nice rafting Adventure with Nature Knights

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