n.

1. 1. The energy produced by running or falling water that is used for driving machinery, especially for generating electricity.
   2. A source of such energy, as a waterfall.
2. A water right owned by a mill.

For more information on waterpower, visit Britannica.com.

Waterpower is the product of falling water acting by impact, weight, or reaction on a wheel. For many centuries the simpler forms of waterwheels were made of wood and varied in diameter and breadth of rim, with flat or concave paddles or hollow troughs, known as buckets, attached around the circumference. Power came directly from water flow past a streamside (or boat-affixed) paddlewheel with paddles that dipped into the stream current. The noria, probably the most ancient of waterwheels and still widely used throughout the world, was of this type; it raised water from the powering stream by means of small vessels attached around the circumference.

A far more common and useful method of generating waterpower was to locate the wheel near an abrupt descent in the streambed (that is, a waterfall). By raising a simple dam of earth, rocks, or timber across the stream above the waterfall, the amount of descent was increased. The water was diverted into a ditch called a race and conveyed to the waterwheel, located beside or beneath the mill at a convenient site downstream. With a descent of several feet, a modest wheel in a small brook might deliver as much as two to three horsepower, sufficient to drive a small gristmill, sawmill, or fulling mill.

The watermills that served the frontier settlers of eighteenth-and nineteenth-century America greatly eased the more arduous tasks. The most common watermill on the American frontier was the gristmill, by which grain was reduced between millstones to the meal that was the basis of the settlers' diet. Later, the sawmill made it possible to replace log cabins with wood-frame dwellings.

Before the development of steam-driven machinery early in the nineteenth century, the alternative to the water-powered mill was the windmill. But the numerous and extensive river systems of the United States, particularly along the Atlantic coast, provided a wealth of waterpower. Waterpower fueled the early industrialization of the eastern seaboard. By 1840 there were well over fifty thousand gristmills and sawmills in use, half of them in the Middle Atlantic states and New England.

Waterpower complexes, of which the largest were found on the Merrimack and Connecticut Rivers in New England, provided the power base of some of the country's largest industrial centers, with the mills at Lowell, Massachusetts, driven by the powerful Pawtucket Falls, as the prototype and exemplar. These great waterpower complexes, dating from the 1820s, used great wooden wheels fifteen or more feet in diameter and of equal or greater width. These so-called breast-wheels were quite similar to the paddlewheels of river steamboats, except for the wooden troughs that replaced the flat paddles. The invention of the turbine marked an advance in efficiency, economy, and rotating speeds. Developed in Europe, particularly by the French engineer Benoit Fourneyron (1827), the turbine was improved in the United States, notably at Lowell, where Uriah A. Boyden, in 1844, and James B. Francis, in 1851, developed the most common type of modem water turbine. The other significant type of water turbine, the "impulse" turbine, for use in small streams that fall very steeply, was also developed in the United States.

After 1860 the rapid extension of the railway network doomed the widely distributed industries located along streams in small towns. As the advantages of large urban centers became apparent—increased labor supply; financial, commercial, and supply services; and transportation facilities—the centralization of manufacturing industries in large cities gathered momentum. Since few large cities possessed appreciable waterpower, their growth depended on steam power and access to coal, which was widely available through rail and water transport. Marked advances in the efficiency of steam engines and boilers in the late nineteenth century negated the cost advantage long enjoyed by waterpower. By 1870 steam power passed waterpower capacity in manufacturing nationwide, and in succeeding decades it left waterpower far behind.

The success of the Niagara hydroelectric power project of the early 1890s signaled the beginning of a new age in the history of waterpower. Based on the electrical transmission of energy, hydroelectric power bore little significant relation to the traditional, direct-drive waterpower in which each establishment, small or large, had its own power plant, with most establishments leasing the use of the water by which its wheels were driven. After 1900 hydroelectric power was produced in plants of enormous capacity and distributed over long distances by high-tension power lines.

Bibliography

Hunter, Louis C. A History of Industrial Power in the United States, 1780–1930. Charlottesville: University Press of Virginia, 1979.

McKelvey, Blake. Rochester, the Water-Power City, 1812–1854. Cambridge, Mass.: Harvard University Press, 1945.

Pisani, Donald J. To Reclaim a Divided West: Water, Law, and Public Policy, 1848–1902. Albuquerque: University of New Mexico Press, 1992.

Pugh, Brinley. The Hydraulic Age: Public Power Supplies Before Electricity. London: Mechanical Engineering Publications, 1980.

Note: click on a word meaning below to see its connections and related words.

The noun has one meaning:

Meaning #1: the power to do work that is latent in a head of water

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Dansk (Danish)
n. - vandkraft

Nederlands (Dutch)
waterkracht, witte elektriciteit

Français (French)
n. - énergie hydraulique

Deutsch (German)
n. - Wasserkraft

Ελληνική (Greek)
n. - υδραυλική ενέργεια

Italiano (Italian)
energia idroelettrica

Português (Portuguese)
n. - energia hidráulica (f)

Русский (Russian)
гидроэнергия

Español (Spanish)
n. - energía hidráulica, energía hidroeléctrica, salto de agua

Svenska (Swedish)
n. - vattenkraft

中文（简体） (Chinese (Simplified))
水力, 水力发电

中文（繁體） (Chinese (Traditional))
n. - 水力, 水力發電

한국어 (Korean)
n. - 수력

日本語 (Japanese)
n. - 水力

العربيه (Arabic)
‏(الاسم) القوة المائيه أي قوة الماء المستعمله لتحريك آلات, شلال لائق لتحريك آلات‏

עברית (Hebrew)
n. - ‮כוח מים (בטורבינה), כוח המים הנובע מהזרימה או ממפל-מים‬

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