CANALS AND INLAND WATERWAYS


Meaning of CANALS AND INLAND WATERWAYS in English

natural or artificial waterways used for navigation, crop irrigation, water supply, or drainage. Despite modern technological advances in air and ground transportation, inland waterways continue to fill a vital role and, in many areas, to grow substantially. This article traces the history of canal building from the earliest times to the present day and describes both the constructional and operational engineering techniques used and the major inland waterways and networks throughout the world. Transport by inland waterways may be by navigable rivers or those made navigable by canalization (dredging and bank protection) or on artificial waterways called canals. Many inland waterways are multipurpose, providing drainage, irrigation, water supply, and generation of hydroelectric power as well as navigation. The lay of the land (topography) and particularly changes in water levels require that many rivers be regulated to make them fully navigable, thus enabling vessels to proceed from one water level to another. The chief regulating method is the lock, the development of which contributed significantly to the Industrial Revolution and the development of modern industrial society. For many types of commodities, particularly such bulk commodities as grains, coal, and ore, inland waterway transport is still more economical than any other kind of transport. Thus, it is hardly surprising that modernized inland waterways, using the latest navigational aids and traction methods and traversing the great landmasses of North America, Europe, and Asia, play an increasingly important economic role. Additional reading Coverage of both Old and New World inland waterways is provided by Charles Hadfield, World Canals: Inland Navigation Past and Present (1986), heavily illustrated. L.T.C. Rolt, Navigable Waterways (1969), provides a descriptive account of inland waterway networks.J. Phillips, A General History of Inland Navigation, Foreign and Domestic, 5th ed. (1805, reprinted as Phillips' Inland Navigation, 1970), contains a complete account of the canals built in England up to the end of the 18th century. Ruth Delany, Ireland's Royal Canal: 17891992 (1992), details the history of the canal from its beginnings through its years of decline and disuse to its late 20th-century restoration. Osborne Mance (Harry Osborne Mance), International River and Canal Transport (1944), chronicles the history of the commissions controlling and regulating operations on the international waterways up to the end of World War II. Roger Calvert, Inland Waterways of Europe, 2nd ed. (1975), contains a nontechnical account of the principal European inland waterway systems, including interesting diagrams, maps, useful itineraries, and an international bibliography.Discussions of the growth and importance of canals in the history of the United States are found in Ronald E. Shaw, Erie Water West: A History of the Erie Canal, 17921854 (1966, reprinted 1990), and Canals for a Nation: The Canal Era in the United States, 17901860 (1990); and Russell Bourne, Floating West: The Erie and Other American Canals (1992).Two well-known international canals are treated in D.A. Farnie, East and West of Suez: The Suez Canal in History, 18541956 (1969), a comprehensive and detailed study of the history of the Suez Canal and of its impact on the foreign policies of the imperial powers in relation to the Middle East; and David McCullough, The Path Between the Seas: The Creation of the Panama Canal, 18701914 (1977), a history of the canal's construction. Ernest Albert John Davies Christopher Marriage Marsh The Editors of the Encyclopdia Britannica Modern waterway engineering Waterways are subject to definite geographic and physical restrictions that influence the engineering problems of construction, maintenance, and operation. The geographic restriction is that, unlike roads, railways, or pipelines, which are adaptable to irregular natural features, waterways are confined to moderate gradients; and where these change direction, the summit pounds (ponds) require an adequate supply of water, while valley pounds need facilities for disposal of surplus. The primary physical restriction is that vessels cannot travel through water at speeds possible for road vehicles or railway wagons. Because transport economics are based on the transport unit (x tons moved y miles in 1 man-hour), waterways must provide larger tonnage units than those possible on road or rail in order to be competitive. Modern waterway engineering, therefore, is directed toward providing channels suitable for larger vessels to travel faster by reducing delays at locks or from darkness and other natural hazards. While such channels and associated works are designed to minimize annual maintenance costs, the costs of operating vessels, locks, wharves, and other waterway works can be minimized by increased mechanization. Characteristics of basic types Fundamentally, waterways fall into three categories, each with its particular problems: natural rivers, canalized rivers, and artificial canals. On natural rivers navigation is subjected to seasonal stoppages from frost, drought, or floods, all of which lead to channel movements and to the formation of shoals. While minimizing natural hazards, attention is directed primarily to retaining the channel in a predetermined course by stabilization of banks and bed, by elimination of side channels, and by easing major bends to obtain a channel of uniform cross section that follows the natural valley. On canalized rivers navigation is facilitated by constructing locks that create a series of steps, the length of which depends on the natural gradient of the valley and on the rise at each lock. Associated with the locks for passing vessels, weirs and sluices are required for passing surplus water; and in modern canalizations, such as the Rhne and the Rhine, hydroelectric generation has introduced deep locks with longer artificial approach channels, which require bank protection against erosion and, in some strata, bed protection against seepage losses. On artificial canals navigation can depart from natural river valleys and pass through hills and watersheds, crossing over valleys and streams along an artificial channel, the banks and sometimes the bed of which need protection against erosion and seepage. The route of an artificial canal can be selected to provide faster travel on long level pounds (stretches between locks), with necessary locks grouped either as a staircase with one chamber leading directly to another or as a flight with short intervening pounds. Where substantial differences of level arise or can be introduced, vertical lifts or inclined planes can be constructed. Storage reservoirs must be provided to feed the summit pound with enough water to meet lockage and evaporation losses; other reservoirs can be introduced at lower levels to meet heavier traffic movements entailing more frequent lockage operation. If supplies are insufficient to offset the losses, pumps may be needed to return water from lower to upper levels. Waterway systems Administration Modern inland waterway development has been largely carried out by governments, in contrast to early canal construction, which was mainly undertaken by private enterprise. Most of the older canals were subsequently acquired by the state and are administered by them or their agencies and are subject to comprehensive regulation, frequently by independent commissions. International commissions representing the states concerned regulate navigation on the international waterways. In the United States the waterways are basically a federal responsibility, with their development undertaken by the U.S. Army Corps of Engineers, but state governments and local authorities also participate in the administration of many local waterways. The Interstate Commerce Commission has responsibility for the regulation of the common carriers and requires them to publish their rates. For some major multipurpose projects, public corporations were established to undertake and administer them. In Europe and the former Soviet Union the national networks, mainly based on navigable and canalized rivers linked by canal, were developed by the governments, which retained responsibility for finance and administration. In Britain most canals were brought under government ownership beginning Jan. 1, 1948, and are administered by the British Waterways Board. Europe's main waterways have long been accepted as international waterways with navigation free to all vessels and equality of treatment of all flags guaranteed. The chief regulatory commissions are the Central Commission for the Navigation of the Rhine, the Danube Commission, and the commission for the canalized Moselle. There are also a number of bilateral agreements between states. Wars and political considerations following them have from time to time interrupted the freedom of navigation. A provisional Rhine Commission was operating in the early 1970s; a new Danube Commission was established in 1953 after the signing of the Austrian state treaty, when freedom of navigation throughout the river's length was fully restored. With the creation of a number of international organizations in Europe, a high degree of cooperation between states for the development of the inland waterways and the regulation of navigation was achieved, particularly through the United Nations Economic Commission for Europe, the European Economic Community, the Organization for Economic Cooperation and Development, and the Council of Europe. In North America a U.S.-Canadian International Joint Commission has functioned since 1909 with general authority over the boundary waters. The St. Lawrence Seaway is a joint project, administered by the St. Lawrence Seaway Authority in Canada and the St. Lawrence Seaway Development Corporation in the United States. The Panama Canal was originally administered under the Panama Canal Convention of 1903 by the United States, under the supervision of the army. Panama-U.S. relations were frequently strained, and in 1964 the United States agreed to negotiate new treaties concerning the existing canal and construction of a new canal at sea level. Later both countries agreed to a new treaty recognizing Panama's sovereignty over the Canal Zone. The international status of the Suez Canal, constructed and administered by the Suez Canal Company, has frequently been a matter for dispute, peaceful and otherwise. Only in 1904, under an Anglo-French agreement, was the Constantinople Convention of 1888, establishing the Suez Canal as an international waterway open to all in war and peace, finally implemented. In 1956 British presence in the area ended, and troops were withdrawn from the canal zone; the Egyptian government nationalized the assets of the canal company and the administration was assumed by Egypt, but the 1967 war closed the canal until 1975. Major inland waterways of Europe After the end of World War II, the growth of transport by inland waterway in Europe, coordinated by the various international authorities, resulted in an enlarged and integrated network brought up to a minimum common standard for craft of 1,350 tons. With the Rhine, the Moselle, and their tributaries dominating the German system and providing outlets for the Dutch and Belgian systems and connecting with the French network, main improvements were concentrated on the international Main-Danube Canal and on improving the north-south route of the Nord-Sud Canal (or Elbe-Seitenkanal). The latter canal (completed in 1976) leaves the Elbe about 20 miles above Hamburg and, running south, joins the Mittelland Canal near Wolfsburg, Ger., reaching a total of 711/2 miles and shortening the route between Hamburg and the Ruhr by 134 miles. The Main-Danube waterway connecting the Rhine with the Black Sea was completed in 1992 and provides a route for traffic between eastern and western Europe through Germany, accommodating craft of 1,350 tons throughout its length. Following the Main River to Bamberg in Germany, the route proceeds by artificial waterway, including a section of the Regnitz Canal to Dietfurt, thence by the Altmhl River to a point below Kelheim, where it joins with the Danube, crossing the Austrian border at Jochenstein. The 44-mile Bamberg-to-Nrnberg canal section, completed in 1972, includes seven locks with a combined lift of 268 feet. All locks are 623 feet long and able to accommodate vessels of 1,500 tons. Improvements of the channel of the German Danube, begun in 1965, include a pair of locks at Kachlet, just above Passau. In Austria four pairs of locks to take 1,350-ton craft have been built. The damming of the Danube at erdap (197072), the Iron Gate rapids, on the border between Serbia and Romania, was undertaken in conjunction with the improvement of navigation through these dangerous waters; it incorporates vast hydroelectric power plants. Two locks, 1,017 feet long and 112 feet wide, with two chambers each, are being built to facilitate passage through the Iron Gate. Journey time for ships traveling from Black Sea ports upstream to Belgrade, Vienna, and central Europe will be reduced from approximately 100 to 15 hours by this project, and traffic is expected to rise from the present 12 million tons annually to 50 million tons. France's waterway network of nearly 5,000 miles is based primarily on its rivers, but many of the low-capacity canals are being raised to the 1,350-ton standard. A major development planned in the 1970s in cooperation with West Germany was the construction to this standard of the North SeaMediterranean waterway via the canalized Rhne and Rhine rivers. With four existing locks built for the Grand Canal d'Alsace, a projected lateral canal between Huningue and Strasbourg, the project was modified in 1956, and the four remaining dams were to be built on the Rhine itself and bypassed with short canals including four locks, three with two chambers each. Canalization of the Rhne started with the building of the Port of Edouard-Herriot downstream from Lyon, and work proceeded on 12 locks and dams. Two new ports, serving Valence and Montlimar, were being constructed. Improvements were also made on the Marne-Rhine waterway, which provides an important internal trade route connecting the Paris Basin with the industrial regions of Alsace-Lorraine. The improvements included major works on either side of the Vosges summit level, replacing 23 old locks. At Rchicourt a new lock with a lift of 321/2 feet bypasses six locks and a winding section of the old canal; on the other side of the summit a new canal section bypasses 17 locks, which formerly required 8 to 12 hours to navigate. On this section the inclined plane of Saint-Louis-Arzviller deals with a difference in level of 146 feet with a horizontal length of 422 feet. Two tanks each carry a 350-ton barge. Their 32 wheels run on four rails, and two sets of 14 cables connect the tanks to the two concrete counterweights. Improvements have been made to routes connecting the Seine with the north and east. The Canal du Nord was completed in 1965, and a bottleneck was removed on the Oise Lateral Canal with the building of two locks to accommodate through convoys to Paris. In The Netherlands the extensive canal system based on large natural rivers and serving the ports of Rotterdam and Amsterdam has required comparatively little modernization; but to avoid the Maas (Meuse) River, between Roermond and Maastricht, the Juliana Canal was built in 1935 and improved after World War II. The Twente Canal, opened in 1936, improved communication with the industrial east. Most important of the postwar projects was the building of the Amsterdam-Rhine Canal to enhance the capital's value as a transshipment port. The Noord-Hollandsch Canal from Amsterdam to Den Helder was constructed, and the IJsselmeer was linked with the Ems estuary across the north of Holland. To shorten the distance between Rotterdam and Antwerp by 25 miles, the Schelde-Rhine Canal has been built. Italy's waterway system, based on the Po Valley, is cut off from the European network by the Alps, but it is also being brought up to higher standards. In Scandinavia there are two major commercial artificial waterways: the first, the Trollhtte Canal, connects the Gtalv (river) upward from Gteborg with Lake Vnern and with the Finnish lakes and connecting canals; the second, the Saimaa Canal, in southeast Finland, connecting the vast Saimaa Lake system to the sea, was being reconstructed at the time of World War II. After the Soviet-Finnish War, part was ceded to the Soviet Union; but in 1963 it was leased back to Finland, modernization continued, and the canal, with eight large locks replacing the previous 28, was reopened in 1968. In the Soviet Union, water navigation played a major role in the country's economy; and after World War I its great riversthe Dnepr, Dvina, Don, Vistula, and Volgawere linked to form an extensive network, making through navigation possible from the Baltic to both the Black Sea and the Caspian. The Black Sea and the Baltic are connected by three different systems, of which the most important is the link between the Dnepr and the Bug, a tributary of the Vistula, by way of the Pripyat and Pina rivers, a 127-mile canal connecting with the Mukhavets River, a tributary of the western Bug. This system is the sole wholly inland waterway connection between western Europe and the Soviet systems, giving through access to the Caspian and Black seas. When the Rhine-Danube and Oder-Danube canals are completed, a second route will be provided, via the Berezina River, a tributary of the Dnepr, the Viliya, a tributary of the Niemen, and a 13-mile canal through Latvia to Riga. The last link reaches the Baltic through Lithuania and Poland from the Dnepr by way of the Szara, a tributary of the Niemen; the Jasiolda, a tributary of the Pripyat; and a 34-mile canal. Other important links are the Volga-Don Canal, 63 miles long and completed in 1952, and the Moscow-Volga Canal, built between 1932 and 1937, which flows 80 miles from the Volga to the Moskva River at Moscow. The White SeaBaltic Canal, built in 193133, runs from Belomorsk on the White Sea through the canalized Vyg River across Lake Vyg and through a short canal to Povenets at the northern end of Lake Onega, through which it passes to the canalized Svir River, Lake Ladoga, and the Neva River to the southern terminal at Leningrad. The total length of the system is 140 miles, reducing sea passage between Leningrad and Arkhangelsk by 2,400 miles; through its 19 locks it rises to 335 feet above sea level. In the Soviet Union the Ob and Yenisey in Siberia are connected by canal, and the Karakumsky Kanal has been built from Kerki on the Amu Darya and is being continued westward to the Caspian.

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