Rafting or whitewater rafting is a 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.
History
Rafting is one of the earliest means of transportation, used as a means for shipping people, hunting, and transferring food.
In 1842, Lieutenant John Fremont of the U.S. Army first journalized his rafting expedition on the Platte River. Horace H. Day designed the equipment he used in rafting. Day’s rafts were constructed from four independent rubber cloth tubes and wrap-around floor.
In 1960s, rafting was then recognized and paths like Grand Canyon were routed and whitewater rafting companies were established.
In 1970s, rafting marked its major development as a leisure sport when it was then included in the Munich Olympic Games.
In 1980s, as rafting continued to gain its popularity, a lot of rivers were opened for rafting activities. Rivers in South America and Africa were just a few of them.
In 1990s, rafting was included in major game events like the Barcelona Games in 1992, Atlanta Games in 1996, and the whitewater events of the Summer Olympic Games hosted by Ocoee River in Tennessee Valley. In addition, the International Federation of Rafting was instituted in 1997 and in 1999 the first Official International Championship was held.
Nowadays, river rafting is still gaining popularity among extreme water sports in order to thrill and excite the raft passengers.
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 boat 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.
Classes of Whitewater:
Class 1: Very small rough areas, requires no maneuvering. (Skill Level: None)
Class 2: Some rough water, maybe some rocks, might require maneuvering. (Skill Level: Basic Paddling Skill)
Class 3: Whitewater, small waves, maybe a small drop, but no considerable danger. May require significant maneuvering. (Skill Level: Experienced paddling skills)
Class 4: Whitewater, medium waves, maybe rocks, maybe a considerable drop, sharp maneuvers may be needed. (Skill Level: Whitewater Experience)
Class 5: Whitewater, large waves, maybe large rocks and hazards, maybe a large drop, precise maneuvering (Skill Level: Advanced Whitewater Experience)
Class 6: Whitewater, huge waves, huge rocks and hazards, maybe huge drops. Attempting a Class 6 will most likely end in serious injury or death. If someone navigates a 6 without harm, luck can be given most of the credit. (Skill Level: Expert)
Safety
Whitewater rafting can be a dangerous sport, especially if basic safety precautions are not observed. In the past there have been many accidents; both commercial trips and private trips have seen their share of injuries and fatalities, though private travel has stereotypically been associated with greater risk. Depending on the area, legislated safety measures now exist for rafting operators, ranging from certification of outfitters, rafts, and raft leaders, to more stringent regulations about equipment and procedures. It is generally advisable to discuss safety measures with a rafting operator before signing on for a trip. The equipment used and the qualifications of the company and raft guides are essential information to be considered.
Like most outdoor sports, rafting in general has become safer over the years. Expertise in the sport has increased, and equipment has become more specialized and increased in quality. This is no doubt as a result of the difficulty rating of most river runs has changed. A classic example would be the Colorado River in the Grand Canyon, which has swallowed whole expeditions in the past, leaving only fragments of boats but is now run safely by commercial outfitters hundreds of times each year, with relatively untrained passengers.
Risks in whitewater rafting stem from both environmental dangers and from improper behavior. Certain features on rivers are inherently unsafe and have remained consistently so despite the passage of time. These would include "keeper hydraulics", "strainers" (e.g. fallen trees), dams (especially low-head dams, which tend to produce river-wide keeper hydraulics), undercut rocks, and of course dangerously high waterfalls. Rafting with experienced guides are the safest way to avoid such features. Even in safe areas, however, moving water can always present risks -- such as when a swimmer attempts to stand up on a rocky riverbed in strong current, risking foot entrapment. Irresponsible behavior along the lines of rafting while intoxicated has also contributed to many accidents.
To combat the illusion that rafting is akin to an amusement park ride, and to underscore the personal 
responsibility each rafter faces on a trip, rafting outfitters generally require customers to sign waiver forms indicating understanding and acceptance of the risks. Rafting trips often begin with safety presentations to educate customers about problems that may arise.
Having said all this, the overall risk level on a rafting trip with experienced guides using proper precautions is low. Thousands of people safely enjoy raft trips every year.
Issues with rafting
Like all wilderness sports, rafting has to balance the conflict between nature protection and nature use. Because of frequent problems in the past, some rivers now have regulations restricting or specifying the annual and daily operating times.
Conflicts have also arisen with environmentalists when rafting operators, often in co-operation with municipalities and tourism associations, alter the riverbed by dredging and/or blasting in order to eliminate safety risks or create more interesting whitewater features in the river. Incongruously these measures usually are only temporary, since a riverbed is subject to permanent changes.
On the other hand, rafting contributes to the economy of many alpine regions which in turn may contribute to the protection of rivers from hydroelectric power generation and other development. Additionally, white water rafting trips can promote environmentalism. By experiencing first hand the beauty of a given river, individuals who would otherwise be indifferent to the environmental concerns of an area may gain a strong desire to protect and preserve that area because of a positive outdoors experience.
漂流，也称白水漂流，是使用筏子在江河中或其它水体中进行的娱乐休闲活动。这项活动通常在白水上或不同
级别的汹涌的水中进行，以使筏子乘客得到刺激和兴奋。
历史
漂流是最早的运输方式之一，用来运载人、搜索和运输食品。
1942年，美国陆军中尉约翰·弗里蒙特首次记录了在普拉特河上的漂流探险。贺瑞斯·H·戴伊设计了他用于漂流的设备。戴伊的筏子由4个独立的橡皮布管和环绕的底板组成。
20世纪60年代，漂流得到了公认，诸如大峡谷之类的河流被列为指定路线，白水漂流公司也建立起来了。
20世纪70年代，当漂流被列入慕尼黑奥运会时，标志着它作为休闲运动的较大发展。
20世纪80年代，随着漂流持续得到普及，许多河流对漂流运动开放，包括美洲南部和非洲河流的其中几条。
20世纪90年代，被列入重大比赛项目，如巴塞罗纳奥运会，亚特兰大奥运会和在田纳西河谷奥科伊河举办的夏季奥运会白水项目。此外，国际漂流联盟于1997年成立，{dy}届正式的国际锦标赛于1999年举行。
现在，在极限水上运动中，河流漂流仍然越来越流行，以使乘客感到刺激和兴奋。
白水筏子
筏子是最初是最简单形态的人的运输工具，那时由几根木头、木板或芦苇捆扎到一起做成。今天，充气橡皮船被用作筏子，后来被军队用于海滩攻击。它由很耐用的多层涂橡胶的或乙烯基布及几个独立的气囊组成。其长度为3.5 米 (11呎)到6米(20呎)，宽度为1.8 米 (6呎) and 2.5米(8呎)。与此尺寸规格相比，例外的是便携式筏，它被设计为便携式单人筏，大约小到1.5长，重量低到4磅。
筏有几种不同的形式。在欧洲，最普遍的是用桨在尾部划动的对称筏。其它形式为不对称的舵控制的筏和有中心舵的对称筏。筏通常由普通的桨驱动，典型的容纳人数为4-12人。在俄罗斯，筏通常为手工制造，通常双体形式，有固定在一个框架上的2个充气管。有几对桨来操纵这些筏。双体筏在美国西部也很流行，但通常是摇橹而不是划桨。
白水的级别：
一级：非常微弱的汹涌区域，不需要训练。（技术水平：无）
二级：稍微汹涌的水域，或许有写石头，可能需要训练。（技术水平：基本的划桨技巧）
三级：白水，微小的波浪，可能有小水滴，但没有大的危险。需要大量的训练。（技术水平：有经验的划桨技能）
四级：白水，中等波浪，或许有石头，或许有很大的水滴，可能需要强化训练。（技术水平：白水经验）
五级：白水，大波浪，或许有大石头和危险，或许有大水滴，严格的训练（技术等级：娴熟的白水经验）
六级：白水，巨浪，巨石和巨大危险，或许有巨大的水滴。六级漂流的尝试很可能以重伤和死亡结束。如果有人进行六级漂流而毫发无损，幸运会带来很多赞誉。（技术水平：专家）
安全
白水漂流会是危险的运动，尤其是在基本安全警惕没有被注意的情况下。在过去发生了许多事故；无论是商业旅行还是个人旅行都发生过伤亡，尽管个人旅行一律与较大的冒险相关。根据区域的不同，立法的安全措施现在对于漂流经营者是存在的，范围从运动用品商、筏子和漂流领导的认证到更严格的关于器材和程序的规则。总的来说，在签约进行旅行前与漂流经营者讨论安全措施是明智的。所使用的器材和和公司的资格及漂流指导是应该考虑的基本知识。
和大多数户外运动一样，多年以来，漂流大体上变得gaq。这无疑是多数河流奔腾难度等级变化的结果。一个典型的例子是位于大峡谷的科罗拉多，它在过去吞没了所有的探险队，进留下船的碎片，但现在被商业运动用品商们每年相对都没有受过训练的乘客安全地运营几百次。
白水漂流的风险来自环境危险和不适当的行为。尽管时光在流逝，河流的某些特征具有固有的不安全性并且一直保持这样。这些特征包括“保持体水压”、“过滤网”（如倒下的树）、坝（尤其是低水头坝，容易产生与河流等宽的保持体水压）、下部被削去的岩石和顺理成章的危险的高瀑布。同有经验的向导一起漂流是避开这些特征的zaq的方式。然而，即使在安全区域，流动的水会经常构成危险，例如当一个游泳者试图站在水流很强的多岩石的河床上时，脚有陷下的危险。在极其兴奋时沿着漂流路线不负责任的行为也已造成许多事故。
为了打破漂流在人们心目中像游乐场漂浮一样的幻想，并且强调每个漂流者在旅途中的个体责任，漂流运动用品商们通常要求顾客签署表明理解和接受风险的弃权声明书。漂流旅行通常以安全的陈述开始，以教导顾客可能出现的问题。
已经说了这么多，同使用适当防范措施的有经验的向导一起在漂流旅途中的总的风险级别较低。每年有成千上万的人安全地享受了漂流旅行。
漂流的问题
像许多野外运动一样，漂流运动不得不平衡自然保护和自然利用之间的冲突。由于过去频繁地出现问题，一些河流现在有限制或指定年度的或每日的运营时间的规定。
当漂流运营者，通常与市政当局和旅游协会合作通过挖泥和（或）爆破以排除安全风险或在河流中创造更有趣的白水特征，也同环境保护论着发生冲突。不适当的是，这些措施通常仅仅是暂时的，因为河床处于{yj}的变化中。
另一方面，漂流对许多高山地区的经济发展有贡献，从而可能有助于使河流免受水力发电和其它发展的影响。此外，白水漂流旅行能不能促进环境保护论。通过直接体检tr河流的美丽，由于积极的户外体验，对一个地区环境漠不关心的人们会获得强烈的保护和保持那个区域的愿望。
图片说明（自上至下）：
1．Rafting in Brazil.
在巴西的漂流
2．Packrafting in Alaska.
在阿拉斯加的便携筏漂流。
3．Rafting in Montenegro.
在黑山的漂流。
4. Modern Whitewater Canoe
现代白水轻舟
5. Whitewater on the river Guil (French Alps)
基尔河上的白水（法国阿尔卑斯山）
Note: Whitewater is formed in a rapid, when a river's gradient drops enough to 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.
注：白水是在急流中形成的，当河流的陡度下降很多而形成多泡的或含气的不稳定水流时，多泡的水呈现白色。这个术语也不严格地指不太狂暴但却不安定的水流。
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