A ship canal is a canal especially constructed to carry ocean-going ships, as opposed to barges. Ship canals can be enlarged barge canals, canalized or channelized rivers, or canals especially constructed from the start to accommodate ships.

For a canal to qualify as a ship canal, it must have a minimum depth of at least 5 metres (16.4 feet)^{[clarification needed]}, although many are much deeper. The purpose of a ship canal is:

1. To create a shortcut and avoid lengthy detours.
2. To create a navigable shipping link between two land-locked seas or lakes.
3. To provide inland cities with a direct shipping link to the sea.
4. To provide an economical alternative to other options.

[edit] Important ship canals (by length)

List of important ship canals by length

canal	dimensions	location	notes
White Sea-Baltic Canal	141 miles (227 km) long 3.5 metres deep	Russia	Opened in 1933, is partly a canalised river, partly an artificial canal, and partly some natural lakes. Shallow depth limits modern vessels from using the canal.
Rhine-Main-Danube Canal	106 miles (171 km) long lock dimensions: 190m x 11.45m x 4m	Germany	Opened in 1992, links the large rivers Rhine and Danube, and thus also the North Sea and the Black Sea.
Suez Canal	100 miles (160 km) long 300 metres wide	Egypt	Opened in 1869, links the Mediterranean Sea to the Red Sea.
Volga-Don Canal	62 miles (100 km) long lock dimensions: 140m x 16.6m x 3.5m	Russia	Opened in 1952, connects the Black, Azov, and Caspian Seas.
Kiel Canal	60 miles (98 km) long lock dimensions: 310m x 42m x 14m	Germany	Opened in 1895. Shortens the passage between the North Sea and the Baltic Sea.
Houston Ship Channel	56 miles (91 km) long 161 m wide 14m deep	USA	Connects Houston, Texas to the Gulf of Mexico.
Alphonse XIII Canal	53 miles (85 km) long	Spain	Opened in 1926, mostly canalised river. Links Seville to the Gulf of Cadiz.
Panama Canal	51 miles (82 km) long lock dimensions: 320m x 33.53m x 25.9 m	Panama	Opened in 1914. Links the Caribbean Sea to the Pacific Ocean, creating a shortcut.
Danube-Black Sea Canal	40 miles (64 km) long lock dimensions: 138m x 16.8m x 5.5m	Romania	Opened in 1984. Links the Danube to the Black Sea.
Manchester Ship Canal	35 miles (57 km) long lock dimensions: 170.68m x 21.94m x 8.78m	England	Opened in 1894. Links Manchester to Irish Sea.
Welland Canal	28 miles (45 km) long lock dimensions: 225.5m x 2.3m x 8.2 m	Canada	Opened in 1931. Links Lake Erie to Lake Ontario and is part of the Saint Lawrence Seaway.
Saint Lawrence Seaway	lock dimensions: 225.5m x 2.3m x 8.2 m	Canada, USA	Links Montreal with Lake Superior.

[edit] Navigability

The standard used in the European Union for classifying the navigability of inland waterways is the European Agreement on Main Inland Waterways of International Importance (AGN) of 1996, adopted by The Inland Transport Committee of the United Nations Economic Commission for Europe (ECE), which defines the following classes:^[1] (This table is incomplete.)

Class	Tonnage (t)	Draught (m)	Length (m)	Width (m)	Air Draught (m)	Description
Class III	1,000
Class IV	1,000–1,500	2.5	80–85	9.5	5.2–7.0	Johann Welker[1]
Class Va	1,500–3,000	2.5–2.8	95–110	11.4	5.2–7.0–9.1	Large Rhine[1]
Class VIb	6,400–12,000	3.9	140	15	9.1	[1]
Class VII	14,500–27,000	2.5–4.5	275–285	33.0–34.2	9.1	[1]

[edit] References

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