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Definition: canal from Dictionary of Energy

Transportation. 1. an artificial waterway that is dug to connect two adjacent bodies of water to allow for the passage of shipping between them. 2. a similar waterway dug to conduct water across an extent of land for irrigation or drainage.

Summary Article: canal
From The Hutchinson Unabridged Encyclopedia with Atlas and Weather Guide

Artificial waterway constructed for drainage, irrigation, or navigation. Irrigation canals carry water for irrigation from rivers, reservoirs, or wells, and are designed to maintain an even flow of water over the whole length. Navigation and ship canals are constructed at one level between locks, and frequently link with rivers or sea inlets to form a waterway system. The Suez Canal in 1869 and the Panama Canal in 1914 eliminated long trips around continents and dramatically shortened shipping routes.

Irrigation canals The River Nile has fed canals to maintain life in Egypt since the earliest times. The division of the waters of the Upper Indus and its tributaries, which form an extensive system in Pakistan and Punjab, India, was, for more than ten years, a major cause of dispute between India and Pakistan, settled by a treaty in 1960. The Murray basin, Victoria, Australia, and the Imperial and Central Valley projects in California, USA, are examples of 19th- and 20th-century irrigation-canal development. Excessive extraction of water for irrigation from rivers and lakes can cause environmental damage.

Ship canals Probably the oldest ship canal to be still in use, as well as the longest, is the Grand Canal in China, which links Tianjin and Hangzhou and connects the Huang He (Yellow River) and Chang Jiang. It was originally built in three stages: the first was finished around 486 BC, the second (linking the Chang Jiang and Huang He) was constructed from 605 to 610, and the third between 1282 and 1292. It reaches a total length of approximately 1,600 km/1,000 mi. Large sections silted up in later years, but the entire system was dredged, widened, and rebuilt between 1958 and 1964 in conjunction with work on flood protection, irrigation, and hydroelectric schemes. It carries millions of tonnes of freight every year.

Where speed is not a prime factor, the cost-effectiveness of transporting goods by canal has encouraged a revival; Belgium, France, Germany, and the states of the former USSR are among countries that have extended and streamlined their canals. The Baltic–Volga waterway links the Lithuanian port of Klaipeda with Kahovka, at the mouth of the Dnieper on the Black Sea, a distance of 2,430 km/1,510 mi. A further canal cuts across northern Crimea, thus shortening the voyage of ships from the Dnieper through the Black Sea to the Sea of Azov. In Central America, the Panama Canal (1904–14) links the Atlantic and Pacific oceans (64 km/40 mi). In North America, the Erie Canal (1825) links the Great Lakes with the Hudson River and opened up the northeast and Midwest to commerce; the St Lawrence Seaway (1954–59) extends from Montréal to Lake Ontario (290 km/180 mi) and, with the deepening of the Welland Ship Canal and some of the river channels, provides a waterway that enables ocean-going vessels to travel (during the ice-free months) between the Atlantic and Duluth, Minnesota, USA, at the western end of Lake Superior, some 3,770 km/2,342 mi.

UK canals As the pace of trade increased in the UK in the 17th and 18th centuries, it was necessary to find a better way of transporting goods than by road, which was slow and subject to accidents, delays, and highway robbery. Water-borne barges could carry 50 times as much as a wagon and as much as 250 packhorses. Before the canals of the 18th century, Parliamentary legislation allowed stretches of river to be made navigable: by 1700, about 1,600 km/1,000 mi of river had been improved.

Although the first British canal was built in 1566, the first major British canal was the Bridgewater Canal 1759–61, constructed for the 3rd Duke of Bridgewater to carry coal from his collieries to Manchester. The engineer, James Brindley, overcame great difficulties in the route. Thomas Telford constructed the Ellesmere Canal, linking Birmingham to North Wales and Liverpool 1793–1803. By the 1790s, ‘canal mania’ had gripped the country. Between 1791 and 1794, 42 canals were financed, at a total cost of £6 million. By 1830 some 6,500 km/4,000 mi of canals had been built. The canal boom was one of the causes of the Industrial Revolution. Building the canals created thousands of jobs, and increased demand in the wood, brick, and clay industries. It also helped to develop civil engineering skills. The canals brought cheap coal and fresh food to the growing towns, and helped businesses by reducing transport costs. Thousands of navvies were employed in their construction, and thousands more were needed to run them. The large amounts of money raised to build the canals led to the foundation of stock exchanges, which could then be used to raise money for industry.

However, canals were slow, unsuitable for carrying passengers, and expensive to build, especially in the hill country of the north of England and Scotland, where most industrial development was taking place. After 1850 the canals were replaced by the railways as the main form of transport. Today many of Britain's canals form part of an interconnecting system of waterways some 4,000 km/2,500 mi long. Many that have become disused commercially have been restored for recreation and the use of pleasure craft.


Development of railways

The Transport Revolution, 1750–1900

Effects of transport revolution

Development of canals


British Waterways

Canals: Panoramic Photographs, 1851–1991


Amsterdam canal

Bangkok canal

Dublin canal

Paddington Canal

Panama Canal

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