A world-first coral rescue for Nakheel

Nic Ridley, Business 24/7 5 Jun 09;

Even for a builder of Palm islands, the task of moving Dubai's biggest coral reef away from the effects of future development would raise more than a few problems for Nakheel.

The reef had been discovered at Dubai Dry Docks' breakwater, a site that had been chosen as a land-base for firms building on The World archipelago.

Experts quickly dismissed traditional methods of moving coral as too damaging to the fragile marine creatures

So scientists and engineers hatched a plan, believed to be a world-first, which involved moving more than 1,100 coral-encrusted rocks, each weighing about five tonnes.

But they had to be removed, lifted, and transported by barge without them ever leaving the water.

Now, Nakheel said the painstaking process, which took five weeks, has been a success and the coral was thriving at its new home, coincidentally on The World's breakwater.

"Traditionally, when coral is moved it is chiselled or drilled from rocks, placed in baskets and shipped to a new location," said Brendan Jack, Head of Sustainability and Environment for Nakheel Northern Projects.

"That wasn't open to us because each of the rocks was encased in coral, so we went back to the drawing board to find an engineering solution. This operation took considerable time and effort and, importantly, money and illustrates the extent to which Nakheel takes seriously its environmental management responsibilities.

"Nothing like this has ever been attempted before and we are very pleased with the outcome."

Typically, up to 30 per cent of coral dies when traditional relocation techniques are used. Seven per cent of coral died during Nakheel's operation.

Details of the relocation were kept under wraps for more than a year to ensure its success. It has been announced now to coincide with World Environment Day today.

Independent scientific study of the coral is continuing. A scientific peer-reviewed research paper will be published once the study is complete in the coming months.

The reef was discovered when an environmental assessment was carried out by Nakheel, consultants GHD and scientists on the 25-year-old breakwater.

Marine biologist John Burt, Assistant Professor at Zayed University, was brought on board as an independent expert and regularly visits the site to check on the progress of the coral.

He said: "What we found [in the initial assessment] was the biggest coral reef in Dubai and an area of extreme importance. Because of the conditions in the Gulf – where the water temperature can reach 35C and drop to 15C – coral has difficulty establishing itself.

"However, it has learned to adapt and we believed it was important to do everything we could to protect this reef.

"We could not take all of the coral. In some places the water was too shallow for the crane so the rocks had to be left. I believe once development around the Dry Docks breakwater begins the remaining coral has no chance of survival."

The operation involved engineers and divers drilling an iron bolt into each of the rocks and attaching a sling to hoist them from their resting place.

The rocks were not raised out of the water to ensure the delicate coral did not suffer from further, potentially fatal, stress. Instead each rock was attached by its sling to mountings welded to the deck of a 90-metre barge and left hanging in the water.

Once 20 were attached, the barge motored at no more than two knots (3.7kph) for more than 15km to the breakwater of The World where the rocks were carefully lowered into place.

The process was repeated for 49 days until 1,129 rocks were relocated. The total area now covered by coral at The World is 6,560sq m. Nakheel has asked the precise location of the new reef is not disclosed to avoid commercial and recreational fishing.

However, once the new coral colony is firmly established it could become a recognised dive site.

A Nakheel spokesman said:?"Initial observations show the project has been extremely successful with damage kept to a minimum, as indicated by a lack of breakage and stress.

"As the coral continues to thrive the waters around The World will see an increase in coral cover and diversity in the long term and will also attract reef-associated fish.

"A number of the dominant corals, now at The World, are 'broadcast spawners' and their reproductive activities could result in the development of coral on nearby rocks."