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50-522: The middle fork is an exceptionally popular and difficult whitewater rafting and kayaking destination. Given Federal protection in 1980, the wilderness area it lies within is part of the largest roadless tract left in the lower 48 states. The Middle Fork is a heavily whitewatered 104-mile-long (167 km) tributary of the Salmon River , the main tributary of the Snake River , which in turn

100-467: A boatsman with passengers having no direct responsibilities. Catarafts can be of all sizes; many are smaller and more maneuverable than a typical raft. 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 be "open", resembling the typical canoe. This type of canoe is usually referred to simply as an "open boat". Whitewater canoes are paddled in

150-455: A bucket, and because the only way to get water out of them is by bailing with a bucket. Catarafts are constructed from the same materials as rafts. They can either be paddled or rowed with oars. Typical catarafts are constructed from two inflatable pontoons on either side of the craft that 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

200-413: A canoe. C1s are similar in construction to whitewater kayaks, but 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 have a spraycover, essentially the same type used in kayaking. Like kayaks, C1s can be righted after capsizing with an Eskimo roll. McKenzie River dory (or "drift boat" by some)

250-493: A low kneeling position, with a one-bladed paddle. Open whitewater canoes often have large airbags and in some cases foam, usually 2-lb density ethyl foam, firmly attached to the sides, to displace water in the boat when swamped by big waves and holes and to allow water to be spilled from the boat while still in the river by floating it up on its side using the foam and bags. Like kayaks, whitewater canoes can be righted after capsizing with an Eskimo roll, but this requires more skill in

300-424: A lower rated rapid may give a better "ride" to kayakers or rafters, while a Class V may seem relatively tame. However, it is not so much the "ride," but the inherent danger in the rapid. An exiting rapid may have minimal risk, while a seemingly simply rapid may have terminal hydraulics, undercut rocks, etc.) A rapid's grade is not fixed, since it may vary greatly depending on the water depth and speed of flow. Also,

350-485: A river is the rate at which it changes elevation along its course. This loss determines the river's slope, and to a large extent its rate of flow (velocity). Shallow gradients produce gentle, slow rivers, while steep gradients are associated with raging torrents. Constrictions can form a rapid when a river's flow is forced into a narrower channel. This pressure causes the water to flow more rapidly and to react to riverbed events (rocks, drops, etc.). A boulder or ledge in

400-612: 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 , a very popular rafting and kayaking river in Pennsylvania. Of about nine people who have died at or near Dimple Rock, including three in 2000, several of the deaths were the result of people becoming entrapped after they were swept under

450-402: A stream bed, on a floodplain , in an alluvial fan or beach , or in similar settings. Alluvium is also sometimes called alluvial deposit . Alluvium is typically geologically young and is not consolidated into solid rock. Sediments deposited underwater, in seas, estuaries , lakes, or ponds, are not described as alluvium. Floodplain alluvium can be highly fertile, and supported some of

500-418: A strong sideways or diagonal (also called a "lateral") wave can throw the craft off if the craft hits sideways or at an angle. The safest move for a whitewater boater approaching a lateral is to "square up" or turn the boat such that it hits the wave along the boat's longest axis, reducing the chance of the boat flipping or capsizing. This is often counterintuitive because it requires turning the boat such that it

550-486: A surfer slipping out the end of the pipeline, where the wave no longer breaks. Low-head dams are insidiously dangerous because their danger cannot be easily recognized by people who have not studied swift water. (Even 'experts' have died in them.) Floating debris (trees, kayaks, etc.) is often trapped in these retroflow 'grinders' for weeks at a time. Waves are formed in a similar manner to hydraulics and are sometimes also considered hydraulics, as well. Waves are noted by

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600-438: Is 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. River bugs are small, single-person, inflatable craft where a person's feet stick out of one end. River bugging is done feet first with no paddle. Creature Craft are

650-513: Is a short list of them: Whitewater kayaks differ from sea kayaks and recreational kayaks in that they are better specialized to deal with moving water. 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 now, although some paddlers (especially racers and "squirt boaters") use kayaks made of fiberglass composites. Whitewater kayaks are fairly stable in turbulent water, once

700-450: Is dependent upon both seasonal variation in precipitation and snowmelt and upon release rates of upstream dams. 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. The gradient of

750-402: Is no longer parallel to the current. 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 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 normally signal that a rock

800-581: Is not undercut. Pillows are also known as "pressure waves". Eddies are formed, like hydraulics, on the downstream face of an obstruction. Unlike hydraulics, which swirl vertically in the water column, eddies revolve on the horizontal surface of the water. Typically, they are calm spots where the downward movement of water is partially or fully arrested—a place to rest or to make one's way upstream. However, in very powerful water, eddies can have powerful, swirling currents that trap or even can flip boats and from which escape can be very difficult. Located between

850-491: Is the International Scale of River Difficulty , 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

900-712: Is the main tributary to the Columbia River . The nearest town is Stanley to the southeast. The Middle Fork's elevation starts at 7,000 feet (2,100 m) above sea level and drops down to 3,015 feet (919 m)at its mouth. The 47-mile-long (76 km) Bear Valley Creek and Marsh Creek converge to form the Middle Fork. The Middle Fork has around a hundred tributaries; some of the larger are Rapid River, Loon Creek and Camas Creek, all from 20 to 25 miles (32 to 40 km) in length. The Middle Fork flows through 2,500 square miles (6,500 km) of rugged terrain known as

950-605: Is trapped within the water. This forms an unstable current that froths , making the water appear opaque and white. The term "whitewater" also has a broader meaning, applying to any river or creek that has a significant number of rapids. The term is also used as an adjective describing boating on such rivers, such as whitewater canoeing or whitewater kayaking . 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

1000-608: Is used than on flat water. Running whitewater rivers is a popular recreational sport, but is not without danger. Fast-moving water always has the potential for injury or death by drowning or hitting objects. Fatalities do occur; some 50 people die in whitewater accidents in the United States each year. The dangers can be mitigated (but not eliminated) by training, experience, scouting, the use of safety equipment (such as personal flotation devices , helmets, throw ropes), and using other persons as "spotters". Scouting or examining

1050-625: The Salmon River Mountains , peaks of which reach 10,000 feet (3,000 m). A permit is required to travel down the Middle Fork of the Salmon River, which can be obtained through the Four Rivers Lottery and Permit Reservation System . The Middle Fork of the Salmon River permit season runs from May 28 - Sept. 3. Pre and the post season launches are first-come, first-served. Getting a recreational permit to float

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1100-568: The West in the latter half of August, which began with a three-day, seventy-mile (110 km) float trip down the Middle Fork of the Salmon. Interior Secretary Cecil Andrus , the former (and future) governor of Idaho, was also in the party, joined by his family. Whitewater Whitewater forms in the context of rapids , in particular, when a river 's gradient changes enough to generate so much turbulence that air

1150-645: The 19th century, the term had come to mean recent sediments deposited by rivers on top of older diluvium , which was similar in character but interpreted as sediments deposited by Noah's flood . With the rejection by geologists of the concept of a primordial universal flood, the term "diluvium" fell into disfavor and was replaced with "older alluvium". At the same time, the term "alluvium" came to mean all sediment deposits due to running water on plains. The definition gradually expanded to include deposits in estuaries, coasts, and young rock of marine and fluvial origin. Alluvium and diluvium were grouped as colluvium in

1200-568: The American version of the International Scale of River Difficulty). On any given rapid, a multitude of different features can arise from the interplay between the shape of the riverbed and the velocity of the water in the stream. 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

1250-428: The Middle Fork is notoriously difficult and is awarded through a lottery system. There are a combined total of seven commercial and recreational launches a day. To become a permit holder you have to be 18 years old. The permit holder must work with a group to take care of the fees. The permit cannot be given to someone else, and the permit holder must be there at all times on the river. The permit holder must make sure that

1300-608: The earliest human civilizations. The present consensus is that "alluvium" refers to loose sediments of all types deposited by running water in floodplains or in alluvial fans or related landforms . However, the meaning of the term has varied considerably since it was first defined in the French dictionary of Antoine Furetière , posthumously published in 1690. Drawing upon concepts from Roman law , Furetière defined alluvion (the French term for alluvium) as new land formed by deposition of sediments along rivers and seas. By

1350-576: The eddy and the main current, the eddy line is a swirling seam of green and sometimes white water. Eddy lines vary in size based on the size of the water column, the gradient of the section, and the obstacle creating the eddy. Often containing boils and whirlpools, eddy lines can spin and grab your watercraft in unexpected ways, but if used correctly, they can be a really playful spot. Full slice and half slice boaters are able to perform tricks like stern squirts and cartwheels, but nobody uses eddy lines as well as squirt boaters(link to squirt boating wiki), who use

1400-402: The flow rate. In large rivers with high flow rates next to an obstruction, "eddy walls" can occur. An eddy wall is formed when the height of the river is substantially higher than the level of the water in the eddy behind the obstruction. This can make it difficult for a boater, who has stopped in that particular eddy, to re-enter the river due to a wall of water that can be several feet high at

1450-406: The force of the water will pin an object or body against the strainer and then pile up, pushing it down under water. For a person caught in this position, getting to safety will be difficult or impossible, often leading to a fatal outcome. Strainers are formed by many natural or man-made objects, such as storm grates over tunnels, trees that have fallen into a river ("log jam"), bushes by the side of

1500-407: 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. (In many cases,

1550-443: The large, smooth face on the water rushing down. Sometimes, a particularly large wave also is 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 (also called "whitecaps" or "haystacks"). 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

Middle Fork Salmon River - Misplaced Pages Continue

1600-408: The late 19th century. "Colluvium" is now generally understood as sediments produced by gravity-driven transport on steep slopes. At the same time, the definition of "alluvium" has switched back to an emphasis on sediments deposited by river action. There continues to be disagreement over what other sediment deposits should be included under the term "alluvium". Most alluvium is Quaternary in age and

1650-516: The level of development in rafting/kayaking technology plays a role. Rapids that would have meant almost certain death a hundred years ago may now be considered only a Class IV or V rapid, due to the development of certain safety features. 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 that are usually easy can contain lethal and unpredictable hazards (briefly adapted from

1700-481: The middle of a river or near the side can obstruct the flow of the river, and can also create a "pillow"; when water flows backwards upstream of the obstruction, or a "pour over" (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

1750-472: The most dangerous types of holes are formed by low-head dams ( weirs ), and similar types of obstructions. In a low-head dam, the 'hole' has a very wide, uniform structure with no escape point, and the sides of the hydraulic (ends of the dam) are often blocked by a man-made wall, making paddling around, or slipping off, the side of the hydraulic, where the bypass water flow would become normal (laminar), difficult. By (upside-down) analogy, this would be much like

1800-435: The object under the water. In a river, swimming aggressively away from the strainer and into the main channel is recommended. If avoiding the strainer is not possible, one should swim hard towards it and try to get as much of one's body up and over it as possible. Sweepers are trees fallen in or heavily leaning over the river, still rooted on the shore and not fully submerged. Their trunks and branches may form an obstruction in

1850-402: The object. Holes can be particularly dangerous—a boater or watercraft may become stuck under the surface in the recirculating water—or entertaining play-spots, where paddlers use the holes' features to perform various playboating moves. In high-volume water flows, holes can subtly aerate the water, enough to allow craft to fall through the aerated water to the bottom of a deep 'hole'. Some of

1900-705: 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 " Eskimo roll ", or simply "roll". Kayaks are paddled in a low sitting position (legs extended forward), with a two-bladed paddle. See Whitewater kayaking . 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; see rafting . While most rafts are large multipassenger craft,

1950-433: The point at which the eddy meets the river flow. A marked increase or decrease in flow can create a rapid, "wash out" a rapid (decreasing the hazard), or make safe passage through previously navigable rapids more difficult or impossible. Flow rate is measured in volume per unit of time. The stream flow rate may be faster for different parts of a river, such as if there's an undercurrent. The most widely used grading system

2000-455: The rapids before running them is crucial to familiarize oneself with the stream and anticipate the challenges. This is especially important during flood conditions when the highly increased flows have altered the normal conditions drastically. Alluvium Alluvium (from Latin alluvius , from alluere  'to wash against') is loose clay , silt , sand , or gravel that has been deposited by running water in

2050-440: 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, or " hydraulics ", (also known as "stoppers" or "souse-holes" (see also Pillows ) are formed when water pours over the top of a submerged object, or underwater ledges, causing the surface water to flow back upstream toward

Middle Fork Salmon River - Misplaced Pages Continue

2100-411: 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° angle), the power of eddies increases with

2150-417: The river that are flooded during high water, wire fence, rebar from broken concrete structures in the water, or other debris. Strainers occur naturally most often on the outside curves of rivers where the current undermines the shore, exposing the roots of trees and causing them to fall into the river and form strainers. In an emergency, climbing on top of a strainer may be better so as not to be pinned against

2200-413: The rock. Another major whitewater feature is a sieve, which is a narrow, empty space through which water flows between two obstructions, usually rocks. Similar to strainers, water is forced through the sieve, resulting in higher velocity flow, which forces water up and creates turbulence. People use many types of whitewater craft to make their way down a rapid, preferably with finesse and control. Here

2250-666: The rules, which are given by the United States Forest Service, are followed. An example would be that they must have a fire pan and some sort of portable human waste containment system (groover, WAG BAGs, etc.). The Middle Fork has three hundred raftable rapids. Some of the well-known rapids on the Middle Fork are Dagger Falls, Sulphur Slide, Velvet Falls, the Chutes, Power House, Pistol Creek, Tappan Falls, Red Side, Weber, Cliffside, Rubber, Hancock and Devil's Tooth. All but one of these are class III+ to class IV (on

2300-484: The scale of I to VI International scale of river difficulty classification system), with Dagger Falls being class V. The Middle Fork has six natural hot springs in the first 52 miles (84 km) of the river, Trail Flat, Sheepeater, Sunflower, Whitey Cox, Loon Creek and Hospital Bar. The hot springs vary in temperature and are all very popular places to stop on the river. During his second summer in office in 1978, President Jimmy Carter and his family vacationed in

2350-489: The smallest rafts are single-person whitewater craft, see packraft . Rafts sometimes have inflatable floors, with holes around the edges, that allow water that splashes into the boat to easily flow to the side and out the bottom (these are typically called "self-bailers" because the occupants do not have to "bail" water out with a bucket). Others have simple fabric floors, without anyway for water to escape, these are called "bucket boats", both for their tendency to hold water like

2400-412: The swirling water and crossing currents to dance below the surface of the river. Undercut rocks have been worn down underneath the surface by the river, or are loose boulders which cantilever out beyond their resting spots on the riverbed. They can be extremely dangerous features of a rapid because a person can get trapped underneath them under water. This is especially true of rocks that are undercut on

2450-579: The ultimate whitewater craft, with a roll cage design that protects the occupants if they are to flip in any manner. You can see these creatures drifting down rivers like the Gauley, waiting to be capsized and righted by other enthusiastic river users. Whitewater SUP (Stand Up Paddle Boarding) , similar to traditional flat water stand up paddle boarding, whitewater SUPing involves the use of a stand up paddle board to run whitewater. The boards are typically specially designed for whitewater use, and more safety gear

2500-433: The upstream side. Here, a boater may become pinned against the rock under water. 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 such as limestone rather than igneous rock such as granite . In

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