Evaluating Dubai's island-reclamation project

How green is The World?
Economist.com 17 Mar 08;

ITS DEVELOPERS call the three hundred islands laid out in the shape of the world map just off Dubai’s coast the “most innovative real-estate development on Earth”. These new artificial islands, known as “The World”, are just part of a plan to create hundreds of kilometres of new waterfront for Dubai, attracting visitors and wealthy home-owners from around the (real) world.

The World’s developer, Nakheel, built its first artificial-island chain in Dubai in 2001 in the shape of a palm. By 2007, Palm Jumeirah, as it was called, claimed to be the world’s largest man-made island. Construction of two more giant islands, as well as other projects along the coast, are well underway. In January of this year, the last rock was put into The World's breakwater, which stretches for 27km and uses 34m tonnes of rock. Buyers have already started to move in.

All of Nakheel’s artificial islands are built the same way. Masses of sand are gathered from the seafloor of the Arabian Gulf. The sand is then brought to Dubai and sprayed in a giant arc onto the shallow (10.5 meter) seabed off the coast. The sand piles up until it breaks through the surface of the water and forms an island about 4.5m high. Then a massive breakwater is built around the islands to protect them from the stiff local sea currents. It is expensive work: each development typically costs billions of dollars.

The short-term environmental consequences of this reclamation are clear: the intensive construction of Palm Jumeirah created vast plumes of sediment that turned blue seawater milky and temporarily damaged marine life. It also destroyed turtle nesting sites and the only known coral reef along Dubai’s coast.

But Nakheel contends that the new rocky breakwaters of all these projects are creating vast artificial reefs, habitats for reef fish and meadows of sea grass in between the “fronds” of the Palm Jumeirah. They promise to build new turtle nesting sites. Furthermore, they say that the sandy, seafloor habitat held little marine life—and this habitat is common in the region. On balance, they contend that the environmental impact of the project is positive.

Already, the older reef around the Palm Jumeirah is starting to thrive, it says. Nakheel's website says of Palm Jumeirah's breakwater: “As the island was reclaimed, the fine sediments that were created by the reclamation eventually paved the way for a biologically and organically fertile soil on the sea bed, on which turtles and a variety of fish are living. This will lead to a highly oxygenated water, with excellent visibility for divers and snorkelers.”

But Milton Love, an expert on artificial reefs at the Marine Science Institute at the University of California, poses an interesting question: “Clearly, if you were a worm living in the soft sediment and someone dug your home up and replaced it with rock to form an island, you would be out of luck. On the other hand, if you were a butterfly fish and only lived around reefs, and someone changed the sand bottom to a reef, you might like that. But which view is the ‘right’ one? Strictly speaking, neither one is; it just depends on what a person’s philosophy is”.

If one's philosophy, for example is that the ocean should be largely left alone, then whether reclamation provides homes for more fish will not matter. Others, though, may take a more pragmatic view, thinking that the development has essentially created something from nothing. Indeed, many artificial reefs—scuttled ships and aircraft, sunken tyres and shopping trolleys—house marine life in otherwise empty waters.

That conclusion, however, risks oversimplification. While there may be more substrate for coral to grow, the question of whether there is actually more marine life is complicated. Do artificial structures in the ocean actually promote more life, or do they simply attract it? Dr Love reckons some reefs do one, some do the other and some do both. So while the artificial reefs have certainly created new habitats, it isn’t clear whether this is as a net benefit for the region.

That doesn’t give The World and the other islands a clean green bill of health. And focusing on what goes on under the water risks ignores a bigger question: where is all the fresh water for this paradise coming from? Dubai is famous for a number of things; not among them is a plentiful supply of water. So where do they get water for the swimming pools, spas, gardens, dishwashers and hotel laundries? Most of it comes from desalination plants, which expend a lot of energy and release plenty of carbon dioxide.

Anyone in the market for one of the Dubai islands might want to consider the contradictions inherent in their investment. As our climate continues to change, thanks at least in part to the addition of carbon dioxide in the atmosphere, sea levels will probably keep rising, turning low-lying islands into something less than a paradise.