dimanche 21 juillet 2013

The Great Sahara Sea That Almost Was




In 1874, Captain Francois-Elie Roudaire, a geographer in the French army proposed a daring idea. No doubt inspired by the successful completion of the Suez canal a few years earlier, he suggested the creation of a 120-mile-long canal that would connect the Mediterranean Sea to a part of the Sahara Desert in Algeria that lies below sea level. The result would be the flooding of more than 3000 square miles of territory. Roudaire hoped that such a huge body of water would not only allow ships to navigate into the interior of North Africa, it would also significantly change the local climate. All at a cost of a mere 25 million francs.

Waterfront property in Timbuctoo.

The engineer behind the construction of the Suez Canal, Ferdinand de Lesseps, gave Roudaire's scheme his blessing, which was all the French public needed to hear, what with de Lesseps being a national hero and all. The French Academy of Sciences pitched in with a special commission and the French government pledged 35,000 francs to get the ball rolling. Most of this was earmarked to send an expedition, led by Roudaire, to North Africa to study the feasibility of the plan.

The London Times said that the plan "dazzles the imagination, yet it has a sufficiently substantial basis to satisfy several shrewd traders in African commerce and some distinguished engineers." The Daily News called the project "the most remarkable that has ever been devised."

This new sea "is sure to be frequented by trading vessels," reported the British magazine All the Year Round, "to carry off the produce of its banks, which will eventually be dotted with groves of date and coconut palms...Hotels, perhaps towns, will spring up on picturesque and eligible sites; luxurious house-boats will float in its most sheltered and shady creeks..."

Roudaire worked tirelessly for the next eight years, but as scientists and engineers gradually turned against the scheme — the former citing bad geography and geology and the latter an expense that had ballooned to over a billion francs — the idea slowly grew out of favor. Not the least problem was the discovery that the chott (a dry salt lake) nearest the Mediterranean was actually above sea level. Roudaire tried to save his scheme by lengthening his canal from about ten miles long to more than a hundred miles while also decreasing the area that would be flooded.

But in spite of all his efforts, the plan was eventually abandoned. Roudaire died not long afterward, at the age of 48 in 1885, of a fever picked up during his final expedition.



Although the Sahara Sea fell out of favor with engineers, politicians and the public, the sheer grandness and audacity of the idea appealed to a best-selling science fiction author. Jules Verne had already alluded to the scheme in his 1877 novel "Off on a Comet!" (a.k.a. "Hector Servadac"), in which he refers the sea as a going concern. But even 30 years later, the idea still attracted him. He describes the construction of the canal in his 1905 novel, "The Invasion of the Sea," as well as the catastrophic creation of the inland sea when an ill-timed earthquake unexpectedly moves the engineer's schedule up.



The idea has never been entirely abandoned, however, and is periodically unearthed. Even the CIA has explored the consequences of flooding the Qattara Depression in Libya. One advantage that intrigues modern engineers is the possibility of generating massive quantities of hydroelectric power. It would require a canal (or a pair of tunnels ,according to one proposal) only 40 miles long to connect the depression with the sea. The drop of 440 feet would be more than sufficient for the generation of power. Concerns over things such as the impact on indigenous peoples and wildlife are among the many major obstacles to these plans.

[Via Archive.org and The Basement Geographer]

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