A summit-level canal, sometimes called a "watershed canal" or just "summit Canal", is an artificial waterway connecting two separate river valleys. The term refers to a canal that rises to cross a summit then falls down the other side. Typically, summit-level canals include a summit pound, a level stretch of water at the highest part of the canal, usually contained by locks that prevent the water from flowing downstream in either direction. Since water flows out when locks open to admit boats, the summit pound must have a water supply. By contrast, a ''lateral canal'' has a continuous fall only.

History

The first canal to connect rivers across a watershed was the

Lingqu Canal The Lingqu () is a canal in Xing'an County, near Guilin, in the northwestern corner of Guangxi, China. It connects the Xiang River (which flows north into the Yangtze) with the Li River (Guangxi), Li River (which flows south into the Gui ...

("Magic Canal") in China which connected the Xiang and Li rivers for military transport. Construction began in 223 BCE and the canal was in use by 214 BCE. [Needham, Joseph and Wang Ling ''Science and Civilisation in China'', Part 3 “Civil Engineering and Nautics” of Volume IV “Physics and Physical Technology” (Cambridge University Press, Cambridge, 1971) Library of Congress Card Number 54-4723 pp 299 & ff ] The Lingqu carried boats and barges over a 30-meter high summit at an elevation of 210 meters, connecting the Yangtze River watershed with the Pearl River watershed. The Lingqu facilitated the unification and creation of China under its first emperor Qin Shi Huangdi. A second Chinese summit-level canal was the

Grand Canal of China The Grand Canal () is a system of interconnected canals linking various major rivers and lakes in North and East China, serving as an important waterborne transport infrastructure between the north and the south during Medieval and premodern ...

.The International Canals Monuments List
This was started in the 4th century BCE with major extensions in 329 CE, But it was the rerouting of the canal in the 1280s to shorten the connection to the new capital

Beijing Beijing, Chinese postal romanization, previously romanized as Peking, is the capital city of China. With more than 22 million residents, it is the world's List of national capitals by population, most populous national capital city as well as ...

at the start of the

Yuan dynasty The Yuan dynasty ( ; zh, c=元朝, p=Yuáncháo), officially the Great Yuan (; Mongolian language, Mongolian: , , literally 'Great Yuan State'), was a Mongol-led imperial dynasty of China and a successor state to the Mongol Empire after Div ...

, crossing the

Yangtze The Yangtze or Yangzi ( or ) is the longest river in Eurasia and the third-longest in the world. It rises at Jari Hill in the Tanggula Mountains of the Tibetan Plateau and flows including Dam Qu River the longest source of the Yangtze, i ...

and

Yellow River The Yellow River, also known as Huanghe, is the second-longest river in China and the List of rivers by length, sixth-longest river system on Earth, with an estimated length of and a Drainage basin, watershed of . Beginning in the Bayan H ...

s, that established it as a summit-level canal. It remained into the modern era as the longest canal in the world at . In Europe, the first summit-level canal was the Stecknitz Canal (1390–1398) in Germany which connected the Stecknitz river to the Delvenau, a tributary of the

Elbe The Elbe ( ; ; or ''Elv''; Upper Sorbian, Upper and , ) is one of the major rivers of Central Europe. It rises in the Giant Mountains of the northern Czech Republic before traversing much of Bohemia (western half of the Czech Republic), then Ge ...

, as part of the Old Salt Route. It used fifteen staunches and had a summit level; the millers only opened the

flash lock A flash lock is a type of lock (water transport), lock for river or canal transport. Early locks were designed with a single gate, known as a flash lock or staunch lock. The earliest European references to what were clearly flash locks were in ...

s on alternate days. The first summit canal to use pound locks was the Briare Canal in France which was completed in 1642. This canal connected the

Loire The Loire ( , , ; ; ; ; ) is the longest river in France and the 171st longest in the world. With a length of , it drains , more than a fifth of France's land, while its average discharge is only half that of the Rhône. It rises in the so ...

valley to that of the

Seine The Seine ( , ) is a river in northern France. Its drainage basin is in the Paris Basin (a geological relative lowland) covering most of northern France. It rises at Source-Seine, northwest of Dijon in northeastern France in the Langres plat ...

to carry the agricultural produce of the Loire to Paris. In many ways it is the ancestor of all modern summit-level canals being fed from its reservoir, Étang de la Gazonne. One of the greatest engineering feat of the 17th century was the

Canal du Midi The Canal du Midi (; ) is a long canal in Southern France (). Originally named the ''Canal Royal en Languedoc'' (Royal Canal in Languedoc) and renamed by French revolutionaries to ''Canal du Midi'' in 1789, the canal is considered one of the g ...

in Southern France opened in 1684, joining the

Garonne The Garonne ( , ; Catalan language, Catalan, Basque language, Basque and , ; or ) is a river that flows in southwest France and northern Spain. It flows from the central Spanish Pyrenees to the Gironde estuary at the French port of Bordeaux � ...

, which drains into the

Atlantic Ocean The Atlantic Ocean is the second largest of the world's five borders of the oceans, oceanic divisions, with an area of about . It covers approximately 17% of Earth#Surface, Earth's surface and about 24% of its water surface area. During the ...

to the

Étang de Thau The Étang de Thau (; ) or Bassin de Thau is the largest of a string of lagoons (''étangs'') that stretch along the France, French coast from the Rhône river to the foothills of the Pyrenees and the border to Spain in the Languedoc-Roussillon. ...

which leads to the

Mediterranean The Mediterranean Sea ( ) is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean basin and almost completely enclosed by land: on the east by the Levant in West Asia, on the north by Anatolia in West Asia and Southern ...

. Its length rises at the western end and falls to the east via 103 locks, one tunnel and three major aqueducts. To solve the water supply problem, the engineer

Pierre-Paul Riquet Pierre-Paul Riquet, Baron de Bonrepos (; 29 June 1609 (some sources say 1604) – 4 October 1680) was the engineer and canal-builder responsible for the construction of the Canal du Midi. Early life Born as Paul Riquet in Béziers, Hérault, Fran ...

constructed a major dam in the Black Mountains and constructed a feeder canal approximately long. A large network of 18th- and 19th-cantury summit-level canals in England, France, and other European countries facilitated the Industrial revolution.

List of major summit-level canals by continent

Asia

;China * Grand Canal *

Europe

France * Canal de Briare *

* Canal du Rhône au Rhin * Canal du Centre * Canal de l'Oise à l'Aisne Germany * Rhine-Main-Danube Canal *

Kiel Canal The Kiel Canal (, until 1948 called in German the ) is a fresh water canal that links the North Sea () to the Baltic Sea (). It runs through the Germany, German states of Germany, state of Schleswig-Holstein, from Brunsbüttel to the Holtenau di ...

England *

Trent and Mersey Canal The Trent and Mersey Canal is a canal in Derbyshire, Staffordshire and Cheshire in north-central England. It is a "narrow canal" for the vast majority of its length, but at the extremities to the east of Burton upon Trent and north of Middl ...

Leeds and Liverpool Canal The Leeds and Liverpool Canal is a canal in Northern England, linking the cities of Leeds and Liverpool. Over a distance of , crossing the Pennines, and including 91 locks on the main line. The Leeds and Liverpool Canal has several small branc ...

Grand Union Canal The Grand Union Canal in England is part of the Canals of the United Kingdom, British canal system. It is the principal navigable waterway between London and the Midlands. Starting in London, one arm runs to Leicester and another to Birmi ...

Kennet and Avon Canal The Kennet and Avon Canal is a waterway in southern England with an overall length of , made up of two lengths of Navigability, navigable river linked by a canal. The name is used to refer to the entire length of the navigation rather than sol ...

Rochdale Canal The Rochdale Canal is in Northern England, between Manchester and Sowerby Bridge, part of the connected system of the canals of Great Britain. Its name refers to the town of Rochdale through which it passes. The Rochdale is a broad canal be ...

Huddersfield Narrow Canal The Huddersfield Narrow Canal is an Navigability, inland waterway in northern England. It runs just under from Lock 1E at the rear of the University of Huddersfield campus, near Aspley, West Yorkshire, Aspley Basin in Huddersfield, to the ju ...

Oxford Canal The Oxford Canal is a narrowboat canal in southern central England linking the City of Oxford with the Coventry Canal at Hawkesbury (just north of Coventry and south of Bedworth) via Banbury and Rugby. Completed in 1790, it connects to th ...

Northern Ireland *

Newry Canal The Newry Canal is an abandoned canal in Northern Ireland. Opened in 1742, it was built to link the Tyrone coalfields to the Irish Sea. The navigable route ran from Lough Neagh via the Upper Bann river to Portadown (approximated 9 miles), then ...

Scotland *

Caledonian Canal The Caledonian Canal connects the Scottish east coast at Inverness with the west coast at Corpach near Fort William in Scotland. The canal was constructed in the early nineteenth century by Scottish engineer Thomas Telford. Route The can ...

Crinan Canal The Crinan Canal is a Canals of the United Kingdom, navigable canal in Argyll and Bute, west of Scotland. It opened in 1801 and connects the village of Ardrishaig on Loch Gilp with Crinan, Argyll, Crinan on the Sound of Jura, providing a navi ...

Forth and Clyde Canal The Forth and Clyde Canal is a canal opened in 1790, crossing central Scotland; it provided a route for the seagoing vessels of the day between the Firth of Forth and the Firth of Clyde at the narrowest part of the Scottish Lowlands. This allow ...

Poland *

Augustów Canal The Augustów Canal (, , ) is a cross-border canal built by the Congress Kingdom of Poland in 19th century in the Augustów Voivodeship (present-day Podlaskie Voivodeship of northeastern Poland and Grodno Region, Grodno Oblast of western Belarus ...

Russia *

White Sea – Baltic Canal White is the lightest color and is achromatic (having no chroma). It is the color of objects such as snow, chalk, and milk, and is the opposite of black. White objects fully (or almost fully) reflect and scatter all the visible wavelen ...

Volga–Baltic Waterway The Volga–Baltic Waterway (), formerly known as the Mariinsk Canal System (), is a series of canals and rivers in Russia which link the Volga with the Baltic Sea via the Neva. Like the Volga–Don Canal, it is part of the Unified Deep Water ...

Sweden *

Göta Canal The Göta Canal () is a Swedish canal constructed in the early 19th century. The canal is long, of which were dug or blasted, with a width varying between and a maximum depth of about .Uno Svedin, Britt Hägerhäll Aniansson, ''Sustainab ...

North America

United States *

Chesapeake and Delaware Canal The Chesapeake & Delaware Canal (C&D Canal) is a -long, -wide and -deep ship canal that connects the Delaware River with the Chesapeake Bay in the states of Delaware and Maryland in the United States. In the mid-17th century, mapmaker Augus ...

Erie Canal The Erie Canal is a historic canal in upstate New York that runs east–west between the Hudson River and Lake Erie. Completed in 1825, the canal was the first navigability, navigable waterway connecting the Atlantic Ocean to the Great Lakes, ...

Morris Canal The Morris Canal (1829–1924) was a toll road, common carrier Anthracite, anthracite coal canal across North Jersey, northern New Jersey that connected the two industrial canals in Easton, Pennsylvania across the Delaware River from its weste ...

Canada *

Rideau Canal The Rideau Canal is a 202-kilometre long canal that links the Ottawa River at Ottawa with the Cataraqui River and Lake Ontario at Kingston, Ontario, Canada. Its 46 Lock (water navigation), locks raise boats from the Ottawa River 83 metres (272 ...

Panama *

Panama Canal The Panama Canal () is an artificial waterway in Panama that connects the Caribbean Sea with the Pacific Ocean. It cuts across the narrowest point of the Isthmus of Panama, and is a Channel (geography), conduit for maritime trade between th ...

References