World Changing HEY Said It Would Never Happen
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Flood the depressions Trans-Atlantic Unfeasibility aqueduct Benefits Downsides Unfeasibility Benefits Downsides 2 3 We’ve joined oceans and tunnelled under the sea. But some engineers have much grander plans, as Michael Marshall reports WORLD CHANGING HEY said it would never happen. Yet by engineered and designed,” says mega- the time you read this, work should have engineering expert Stanley Brunn of the T begun on a massive new canal to link University of Kentucky in Lexington. the Atlantic and Pacific oceans. Building the So it’s natural to dream even bigger, he says. 278-kilometre-long canal through Nicaragua That may be true. But some of the schemes will require moving billions of tonnes of earth sound like the plans of Bond villains, such as and cost at least $50 billion. If it is eventually flooding California’s Death Valley or nuking YEVINE E completed, it will be wider, deeper and three the isthmus of Panama. Others, like damming UZ/ L times as long as the Panama Canal. Its backers entire seas to generate hydroelectricity, are KOB/ A J claim it will be the biggest engineering project on a mind-boggling scale. Here are seven of A in history. But it is certainly not the biggest the world’s biggest schemes. Could we really ANGELIK ever suggested. “All of us live in places that are go ahead with any of them? And should we? 7 34 | NewScientist | 3 January 2015 150103_F_Megaprojects.indd 34 2014-12-19 12:13 Join Asia and North America Dam the Indian Ocean Unfeasibility Benefits Unfeasibility Downsides 4 Benefits 3 5 Downsides 1Damming the Atlantic Creating land Relink the Pacific Unfeasibility and Atlantic oceans Benefits Unfeasibility Downsides Benefits Unfeasibility Downsides Benefits 6 7 Downsides 3 January 2015 | NewScientist | 35 150103_F_Megaprojects.indd 35 2014-12-19 12:13 Damming Trans-Atlantic Flood the the Atlantic 2 Aqueduct depressions 1It doesn’t get much bigger than this. Northern Africa could do with some In 1905, irrigation engineers3 in California We could build a barrier across the more fresh water. The nearest potential accidentally flooded a depression that lay Strait of Gibraltar (below), effectively source is the world’s second largest river, below sea level. The result was the Salton Sea, turning the Atlantic into a huge dam the Congo, but it flows through a volatile, the largest lake in the state. There have been reservoir. This was first proposed dangerous region. So why not tap the many proposals over the decades for flooding in the 1920s by German architect world’s largest river, the Amazon, instead? other low-lying areas. Herman Sörgel. With the flow of All you’d need is a pipe. A very long pipe. The prime candidate is the Qattara water into the Mediterranean The idea of piping water all the way depression in north-west Egypt, which lies as reduced, the sea would begin to across the Atlantic has been around deep as 130 metres below sea level. It consists evaporate. Allowing it to fall by since at least 1993, when Heinrich of 19,000 square kilometres of sand dunes, 200 metres would create 600,000 Hemmer put it forward in a journal salt marshes and salt pans. The idea is to flood square kilometres of new land. devoted to flights of fancy (Speculations it with seawater from the Mediterranean, The environmental impacts of in Science and Technology, vol 16, p 65). just 50 kilometres to the north. Generating Atlantropa, as this plan is known, He envisaged a pipe 4300 kilometres electricity is the main motive: if water flows would of course be gargantuan. long, carrying 10,000 cubic metres of in at the same rate as it evaporates, generation Perhaps most, er, damning of all, water per second, enough to irrigate could continue indefinitely. The “Qattara Sea” lowering the Med by 200 metres 315,000 square kilometres. would become ever more saline, but would raise sea level in the rest There the matter rested until 2010, surrounding areas might benefit from cooler, of the world by 1.35 metres. “It’s when Viorel Badescu, a physicist at the wetter weather (Climatic Change, vol 5, p 73). impossible in terms of the politics,” Polytechnic University of Bucharest The idea has been around since at least 1912, says Richard Cathcart, a real-estate in Romania, revisited the idea with and the Egyptian government looked into it adviser in Burbank, California, and in the 1960s and 1970s. Few people live in the a mega-projects enthusiast who has “ Underground nuclear Qattara, so politically it is doable. The biggest written several articles and books. problem is the sheer scale of the construction, “Academics are actually afraid to explosions would do which would require tunnels to go under talk about big ideas,” Cathcart says. the trick” a range of hills between the Mediterranean With sea level set to rise tens of and the depression. One construction plan metres over the coming centuries Cathcart. They proposed to submerge a involved nuclear bombs. You may not be because of global warming, Cathcart pipeline 100 metres below the surface, surprised that Egypt abandoned the idea. thinks the idea of a dam across the and anchor it to the seabed at regular Interest in the idea has revived recently Strait of Gibraltar is worth revisiting. intervals (Water Resources thanks to Desertec – a plan to build a vast solar Instead of lowering the Med, a dam Management, vol 24, p 1645). The pipe power plant in North Africa. Magdi Ragheb, could maintain it at its current level, would have to be at least 30 metres a nuclear engineer at the University of Illinois saving low-lying farmland from the wide, and have up to 20 pumping at Urbana-Champaign, has proposed storing sea as well as cities such as Venice stations to keep the water flowing. energy from Desertec by pumping seawater and Alexandria. Egypt in particular It would start offshore in the plume of through a pipeline to storage facilities on top would benefit. As things stand, fresh water from the Amazon – “water of the hills. When more electricity is needed, rising waters will swamp large that has been discarded by the continent this water would be allowed to run down into parts of the Nile delta and displace of South America”, as Cathcart puts it. the depression, turning turbines as it went. millions of people by 2100. All in all, he estimates that the pipeline There would be no need for tunnels. would cost about $20 trillion. Residents Flooding areas like California’s Death Valley of the Sahara, start saving now. would also help offset sea level rise caused by It might be wise to start a bit climate change. But it is not worth doing for smaller – perhaps by piping fresh water this reason alone: even if we flooded all of the 2000 kilometres from lush Papua world’s major depressions, it would barely New Guinea to Queensland in Australia. make a difference. In 2010, businessman Fred Ariel The Salton Sea, meanwhile, is not a great announced plans for a feasibility study advert. It did thrive for decades, but it is now into a $30 billion pipeline. This year, the drying out and dying. Most fish can no longer Y PNG government approved the idea in survive in the ever-saltier water, and frequent ett principle, but Queensland has said the foul smells and toxic dust are driving human LTCE/G plan is not under “active consideration”. residents away. 36 | NewScientist | 3 January 2015 150103_F_Megaprojects.indd 36 2014-12-19 12:14 Join Asia and Dam the North America Indian Ocean 6 Creating land 4 Wherever there’s a narrow5 bit of sea, someone Building artificial islands or peninsulas has suggested installing concrete. The idea has become routine, with some is usually to build a dam in a place where astounding ones being made in Dubai, the water level on one side will drop because for example. But existing methods of evaporation. The resulting difference in require deep quarries and deep pockets. height could be used to generate electricity. Schuiling thinks there is a cheaper There have been various proposals over way to create land. He has shown that ASA GSFC N the years but two stand out. In 2005, mega- injecting sulphuric acid into limestone , , engineering enthusiast Roelof Schuiling, a turns it into gypsum, causing it to swell Riggs GE retired geochemist at Utrecht University in the to up to twice its original size. So where R eo G Netherlands, suggested damming the Gulf in there is limestone close to the surface the Middle East where it opens into the Indian of the sea, new land could be created. The obvious place to link Asia and Ocean. At one point, the Strait of Hormuz, it One such place is Adam’s bridge, North America is at the Bering narrows to just 39 kilometres across. a narrow and shallow strip of shoals Strait (above), in between Russia’s The idea is not to do this anytime soon, stretching for 35 kilometres between north-east corner and Alaska. At its because it is an important shipping route India and Sri Lanka. Schuiling thinks a narrowest point, the strait is just for oil tankers. But when this trade declines, land bridge could be created using his 82 kilometres across, and never Schuiling says, damming the Indian Ocean method for far less than the cost of a more than 50 metres deep. and allowing the level of the Gulf to fall up conventional bridge (Current Science, The idea of a bridge has been to 35 metres could generate 2500 megawatts vol 86, p 1351).