Shipping Lanes

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Shipping Lanes

While any stretch of water which is regularly frequented by ships can be called a shipping lane, it is more meaningful to limit the use of the term to real fairways, in which shipping is limited by the depth of the water or by other navigational hazards and which normally—though not always—are marked by navigational aids. Thus the development of shipping lanes mainly involves navigation to and from ports and through shallow seas or bays, archipelagos, and narrow straits.

On the deep Mediterranean, navigable waters were never in short supply, not even in its connecting straits (the Straits of Gibraltar are over 200 meters deep, and even the Bosporus is 50 to 70 meters deep); yet the first known lighthouse, Pharos, was built at the Nile Delta circa 300 b.c.e., and it has been claimed that, even earlier, fires were burned to guide seafarers into the Hellespontos (Bosporus) or Piraeus. These examples illustrate another important feature connected with fairways: the necessity of being able to locate the entrance, in particular outside a low-lying and featureless coast, such as the Nile Delta, or during the night. They also suggest that such a locating mark often was all that was needed to make a stretch of navigable water a public shipping lane—or at least it was the most visible and permanent mark of the shipping lane's development.

Even a couple of important West European points, La Coruna in northwestern Spain and Boulogne, in France, had their first lighthouses built during Roman times. In the High Middle Ages they were also built in such places as the Danish Sound (in the thirteenth century), the Isle of Wight (after 1314), and Corduan (outside Bordeaux, before 1362). Before about 1500, over twenty lighthouses had been built on the British Isles. On the other hand, Köpu (Dagö), the first lighthouse in the northern Baltic, was commissioned only in about 1520.

Fairways were marked also by such other visual aids as beacons, cairns, and high poles; even prominent buildings, especially churches with their spires, were used for such purposes. In the tidal waters around the North Sea, the sides of navigable channels were marked by spars or branches in the Middle Ages, and even the use of buoys (barrels) seems to date back to the fourteenth century. The diffusion of these innovations to the Baltic periphery is indicated by the orders of the Swedish King Gustav Vasa (in the 1150s) that the main fairways had to be marked with cairns and spar-buoys ("brooms"). Nevertheless, before the end of the sixteenth century, even in Western Europe and the Mediterranean, navigational aids were few and far between, and seafarers depended heavily on local knowledge (and lead line) or the help of local pilots; charts and written route descriptions were rare.

THE DEVELOPMENT OF NEW SHIP TYPES

The transition from Viking long ships to deep and heavy cogs vastly increased the importance of man-made ports with proper quays or wharves. Nevertheless, most natural shipping lanes, even in the Baltic and North Seas, were deep enough for the biggest ships of the early modern period. Thus, for example, the Danish Sound, which now has a certified depth of safe navigation of 7.3 meters, or 24 feet, could easily be passed by the biggest sailing warships, such as Horatio Nelson's Victory, with a full draft of 22 feet, or even the early big steamers from the 1840s such as Brunel's Great Britain, with a draft of 18 feet. It says something of the requirements of global shipping that the Suez Canal, when it first opened in 1869, did not allow the passage of ships any more deeply loaded than those that sailed the Danish Sound. There also were not many important trading ports before the 1870s into which traffic would have been limited by shallow shipping lanes. The only exceptions worth mentioning were a few estuary ports such as Brugge, whose port and entrance were silted up already in the fifteenth century, and St. Petersburg, which for a long time had to load seagoing vessels at its outport, Kronstadt.

The transition to steamships and iron and steel shipbuilding led to a systematic increase in ship sizes. Brunel's supership the Great Eastern (launched in 1858, draft about 28 feet), was an early example. It was not until four decades later, in 1899, that a bigger Atlantic liner was launched. With ships like the Olympic/Titanic (1910–1911, draft 34 feet) and, finally, the Queen Mary (1934, draft 39 feet), the limits of Atlantic liners were pushed further but, even at the end of the 1930s, there were hardly any other ships (except big battleships) that required fairways deeper than about 10 meters. It is illustrative that the first big diesel-powered ocean liners, the Selandia and her sister ships (1912, over 7,000 deadweight tons), still were able to navigate through the Danish Sound. However, after World War I cargo ships of around 10,000 deadweight tons (dwt), drawing some 28 feet, became increasingly common. Just before the war, this tendency had been acknowledged with the dredging of the NordOstsee (Kiell) to a safe passage of 8.5 meters (about 28 feet). The fact that the Suez Canal was deepened to 10 meters (about 33 feet) by 1930 also indicates that bigger sizes were expected to become more common.

The steam age brought other challenges. With increasingly expensive vessels, safe and precise navigation was of growing importance. The late nineteenth century, indeed, became the classical era of lighthouse building. A totally new technology with Fresnel-lenses, steel and concrete construction, plus oil and gas replacing wood or coal as fuel improved the visibility of lights and made it possible to build them farther offshore than before. Many important lighthouses, such as (New) Eddystone, (New) Cape Hatteras or Roter Sand (the first "caisson" lighthouse), date from this era, and scores of older ones were modernized. In addition, large numbers of leading lights and other navigational aids were added around the shipping lanes. This building boom continued until the 1970s, when the increasing use of radar gradually began to make traditional lighthouses almost obsolete.

THE GROWTH OF SHIPS POST–WORLD WAR II

A new "revolution" in shipping lanes started with the rapid growth of ship sizes after World War II. Tina Onassis (1953, 45,000 dwt) has sometimes been called the first supertanker; however, it was only after the first closure of the Suez Canal in 1956 that the growth really started, and a plateau was achieved at the end of the 1970s, when the biggest ships exceeded 500,000 dwt. A parallel, albeit slightly later, development was also experienced in dry cargo shipping. In the mid-1950s, average grain and coal carriers were about 9,000 deadweight tons, slightly smaller than the Liberty ships of World War II. Around 1980, the corresponding averages were around 30,000 dwt (grain) and 50,000 (coal), and by the year 2000 they had increased to over 40,000 and 100,000 dwt. In container shipping, the size boom has been later, but the numbers of "Panamax" ships (around 60,000 dwt, able to carry more than 3,000 20-foot containers) has been rapidly increasing since the early 1980s.

A normal ship of 30,000 dwt draws about 11 meters, a ship of 100,000 dwt about 15 meters, a ship of 250,000 about 20 meters, and a ship of 500,000 dwt about 23 meters. None of these vessels could have passed the Suez Canal in the 1930s, and they exceed the depths of the Danish Sound and the Nord-Ostsee Kanal by even larger margins. Fortunately an alternative route through the Greater Belt, which was developed in the 1960s, lowered the threshold of the Baltic to about 15 meters. Thus this development clearly has created big pressures for those responsible for maintaining safe navigation. Compared with a "Liberty" ship, a 120,000-dwt bulk-carrier is twice as big in all dimensions, which means that it requires fair-ways not only twice as deep but also twice as wide to navigate with safe margins. Such requirements have resulted in increasingly artificial shipping lanes, with limiting shallows blown up or dredged away and with the sides of channels marked with permanent beacons and lights and much greater precision than before. On the busiest waterways, such as the English Channel, it has also led to different traffic control systems.

SEE ALSO Agriculture; Baltic Exchange;Black Sea; Board of Trade, British; Board of Trade, Spanish; Cargoes, Freight; Cargoes, Passenger; Containerization; Cunard, Samuel; Empire, Belgian; Empire, British; Empire, Dutch; Empire, French; Empire, Japanese; Empire, Ming; Empire, Ottoman; Empire, Portuguese; Empire, Qing;Empire, Spanish; EntrepÔt System; Free Ports;Hanseatic League (Hansa or Hanse); Harbors;Indian Ocean; Iran;Mediterranean;Melaka;Packet Boats;Panama Canal;Petroleum;Port Cities;Shipping, Aids to;Shipping, Coastal;Shipping, Inland Waterways, Europe;Shipping, Inland Waterways, North America;Shipping, Merchant;Shipping, Technological Change;Ships and Shipping;Ship Types;South China Sea;Suez Canal.

BIBLIOGRAPHY

Ericsson, Christoffer H., et. al. The Routes of the Sea: Sea Chart from the 16th Century to Present Times. Helsinki: John Nurminen, 1988.

Hutchinson, Gillian. Medieval Ships and Shipping. Exeter: Leicester University Press, 1997.

Kirby, David, and Hinkkanen, Merja-Liisa. The Baltic and the North Seas. London: Routledge, 2000.

Stevenson, David. The World's Lighthouses before 1820. London: Oxford University Press, 1959.

INTERNET RESOURCES

Walker, Jim. "The WWW Virtual Library: The World's Lighthouses, Lightships and Lifesaving Stations." Available from http://www.maine.com/lights/www_vl.htm.

Yrjö Kaukiainen