Origins in early antiquity

As early as in the 3rd century BC, the people of Mesopotamia knew how to take advantage of the Euphrates and Tigris rivers to build canals for irrigating their fields. Presumably, the first man-made navigable waterways were created much later. Egyptian pharaoh Necho II, in the 6th century BC, planned a connection between the Red Sea and the Mediterranean – practically a precursor to today’s Suez Canal. The Canal of the Pharaohs was intended to connect a branch in the eastern Nile Delta with Lake Timsah and via another canal with the Red Sea. It was arguably completed only 350 years later, under Ptolemy II, but then already had locks at the junction with the Gulf of Suez.

Dating back to the 6th century BC as well is the Hong-Gou Canal in China. It linked the Yellow River and the Huai River. Other canal projects followed in the subsequent centuries, particularly for the purpose of linking Beijing and the granaries in the fertile south. Since antiquity, the near-1,800-kilometer (1,118-mile) artificial waterway – still the longest one of all today – has extended from Beijing all the way to the estuary of the Yangtze with the metropolis of Hangzhou (pictured above ). The southern part of this Grand Canal – a UNESCO World Heritage Site – is still used as a regional shipping route nowadays.

Monumental structures

Artificial waterways have been built according to the same principle for thousands of years: Whereas thousands of workers using pickaxes and shovels used to excavate a channel that was subsequently flooded (gallery below), excavators have been doing this job in recent decades – and making progress a lot faster. In addition, the base of the canal today is typically sealed to prevent the water from seeping away.

Arguably, one of the narrowest canals for ships is a unique example of canal construction: The six kilometers (3.7 miles) long and only 25 meters (82 feet) wide Corinth Canal (gallery) separates the Greek mainland from the Peloponnese peninsula. Between 1881 and 1893, it was not dug in the classic sense but rather carved out of the rock. The rock walls of this unique waterway extend up to 76 meters (249 feet) above the water level.

More than in terms of excavation work, engineering knowledge changed with regard to constructing locks and lift locks to overcome the greatest possible differences in elevation with a canal. So for instance, barges traveling the Main-Danube Canal are lifted in 16 locks for an elevation gain of 175 meters (574 feet). In the Belgian Canal du Centre, a vertical lift lock that was the highest up until 2002 lifts the ships by 73.15 meters (240 feet) (gallery) still marking a world record for a canal. Only the lift lock at the Three Gorges Dam of the Yangtze River in China is higher: 113 meters (371 feet).

Canals instead of Cape circling

The canals of the greatest importance to the world economy with strategic significance no doubt include the Panama Canal in Panama and the Suez Canal in Egypt. Since 1914, the Panama Canal with a length of 82 kilometers (51 miles) has shortened a sea voyage from New York City to San Francisco by 15,000 kilometers (9,300 miles): Ever since then, ships have no longer had to navigate the dangerous waters at Cape Horn at the tip of South America. The nearly 170 kilometers (106 miles) long Suez Canal between the Red Sea and the Mediterranean has resulted in a travel distance shortened by more than 10,000 kilometers (6,200 miles) since 1969, obviating the need to navigate the long route from Asia to Europe around the Cape of Good Hope.

Even at the time they were built, both canals were regarded as masterful achievements in waterways engineering. They are continually deepened and widened using state-of-the-art construction technology in order to accommodate the growing number of container ship giants navigating the world’s oceans. More than 17,000 ships pass through the Suez Canal every year and since the most recent expansion in 2016 to the tune of eight billion dollars, about 14,000 ships loaded with up to 14,000 standard containers have been navigating the Panama Canal annually. However, the record of being the world’s most frequently traveled canal with some 32,000 ship passages per year is held by the nearly 100 kilometers (62 miles) long Kiel Canal between Brunsbüttel on the Elbe River and Kiel in Germany that makes it possible for ships to avoid the route through the Scandinavian Skagerrak strait.

Industrialization causes canals to boom

In the interior of countries, entire networks of artificial waterways accelerated trade as well and boosted an economic upswing. For instance, in the early days of industrialization, a canal system with a length of 7,500 kilometers (4,660 miles) was created in the United Kingdom.

In this era referred to as the period of “Canal Fever,” the costs incurred for shipping goods on barges instead of by horse-drawn carriages were cut by more than half. In the course of the 19th century, rail transportation increasingly gained importance. Many of the canals were not upgraded and, as a result, are now too small for commercial ships. Today, they’re primarily used for recreational boating and tourism purposes.

However, around the globe there are still canals that provide important routes for inland shipping, par­ticularly in interaction with rivers or, for instance in North America, lakes as well. In the European part of Russia, a river and canal system with a length of 6,500 kilometers (4,038  miles) (guaranteed draft of 3.6 m / 11.8 ft. for vessels with load carrying capacity of 5,000 metric / 5,511 short tons) links the Baltic Sea, the Barents Sea and the Arctic Ocean in the north and the Black Sea and the Caspian Sea in the south.

Mega projects going forward

Planning of the Nicaragua Canal (see gallery) under China’s leadership has been in progress for more than ten years. The struggle to make this project reality has been going on for at least as long. The link between the Caribbean and the Pacific as an alternative to the Panama Canal – construction costs are estimated to amount to 50 billion dollars – is intended to accommodate even the largest container ships across a distance of 287 kilometers (178 miles) with a water depth of nearly 30 meters (98 feet). However, numerous protests due to environmental concerns, the risks to Nicaragua’s drinking water supply and the displacement of the indigenous population have produced some effects. Whether the canal – particularly after the enlargement of the Panama Canal – will ever be built is anyone’s guess.

The situation won’t be a lot easier for a number of other ambitious canal projects either. The Kra Canal, for instance, is planned to be dug through the south of Thailand in the next decade. The waterway is intended to ease the burden on the heavily frequented Strait of Malacca between Malaysia and Indonesia. Again, China is regarded as the driver of the project being planned as part of the “Maritime Silk Road” initative. Slightly more probable is the construction of Canal Istanbul (gallery) that, alongside the Bosporus, is intended to link the Mediterranean (Sea of Marmara) and the Black Sea. Even before the ground has been broken, the Turkish government officially expects the project – estimated to cost 14 billion euros – to be completed in 2023.

Bearings for the world’s costliest shortcut

The size of the cargo ships navigating the world’s oceans has been steadily increasing over the past decades – so it was logical that the Panama Canal had to grow at some point in time as well. In mid-2016, following a nine-year construction period, the new, third lane of traffic was opened on the waterway that – in terms of the volume of goods shipped – is the second most important one in the world after the Suez Canal. Whereas before only ships with a length of 294 meters (965 feet) and a width of 32 meters (105 feet) were able to navigate the passage, now freighters with a length of up to 366 meters (1,201 feet) and a width of 50 meters (164 feet) fit through the canal. Some 40,000 workers moved 110 million cubic meters (3.9 billion cubic feet) of earth for this purse – 42 times the content of the Great Pyramid of Giza. Estimated costs: 5.25 billion U.S. dollars; included in the price: more than 3,400 rolling bearings from Schaeffler.

The pendulum rolling bearings in the drums of humongous steel cable winches for instance ensure the motion of the lock gates. Due to the high torques, transmissions are additionally required here which in turn are equipped with Schaeffler’s bearing solutions: in this case consisting of tapered and cylinder rolling bearings besides the pendulum types. To prevent wear, a large number of these bearings have been coated with Schaeffler’s Triondur C – this technology enables bearing life of 35 years, with only five-year maintenance intervals: that’s good for global trade requiring 24/7 operation.