Biggest challenges in artificial island construction (IQPC)

An interactive white paper drafted for IQPC, Middle East.

Biggest Challenges in Artificial Island Construction

The Arabs have forever been fascinated with the idea expanding territory over land and sea.

Recently, builders have come up with the most creative designs noted all over the world.

Megastructures which came up in the region recently have certainly helped to place GCC on the map.

Developers, however, are bound to face challenges in a relatively new territory like island and

coastline construction. But overcoming these challenges in such style also means that the GCC is at the forefront of building innovation. Here, we take a look at some of the challenges developers face while building artificial islands and seawalls.

1. Availability of sand

When you decide to build an island or develop a coastline, first ask yourself if you have enough sand, and if the sand is suitable? Dredged sand from the seabed is used, as calcareous sand is preferable for such construction. Usually, islands are composed of sand dredged from shallow coastal waters. In some cases, sand is very expensive and the challenge lies in getting good prices from dredging companies. You must also ensure that the sand dredged from the barren sea bed is well graded.

2. Environmental Damage

Artificial islands come with a high environmental cost. As a result of dredging and re-depositing sand, the sea gets clouded with silt. This damages the marine habitat, buries coral reefs, oyster beds and subterranean fields of seagrass. It also threatens marine species, while beaches erode with disruption of natural currents. With such drastic consequences, it is necessary to collaborate with environmental agencies and follow their prescribed procedures to safeguard the ecosystem and avoid erosion.

3. Coastal maintenance

Palm Jumeirah is a good example of post engineering challenges. As there was no continuous flow of water into the islands, unhealthy beaches due to water stagnation was a big issue. Besides, the island’s fractal shape didn’t help, leading to stagnant water, algae and mosquitoes. The issue was solved when they made two breaks in the sea wall so that the tides entre twice a day. After this, environmentalists made it a point to test the water every day to ensure the water quality.

4. Risk of Liquefaction

If sand has low cohesiveness, and there is an earthquake, a process known as liquefaction can develop. In other words, as an earthquake shakes the earth's surface, sand particles will move, pushing the water between the particles up. This liquefies the ground causes the island to sink in the sea. When this problem was foreseen at Palm Jumeirah, constructors used vibro compaction technology which made loose sand denser by saturating it with high-pressured water an air, and vibrating it with probes. Once the sand was secured in place, additional sand was dumped to fill the remaining space, removing all risks of liquefaction.

5. Logistics

When you build a seawall or an island, you’re transporting construction materials like sand and rocks into the sea. This requires special suppliers who provide barges, tugboats, heavy land-based machines, floating cranes etc. Some marine projects also require rented vessels. Evaluate your requirements thoroughly before you choose your solutions.

6. Ground improvement

Ground improvement is a very expensive process for the builder. One must find the best way to optimise it. Project holders must rely on expert consultants and designers as this step is critical to provide a foundation which can bear capacity. It also takes care of settlement reduction in case of an earthquake by mitigating liquefaction. Besides, ground improvement also takes care of lateral stiffness around pile foundations.

7. Planning Finances

One of the main challenges in artificial island and seawall construction is attracting sponsors for investment. Factors like how developers arrange investments and how they acquire investors are key. For instance, the developers started construction of World Islands but the work was suspended in 2009 owing to the global financial crisis. Besides, the price of your infrastructure is affected by the location of your island. If you chose the wrong location, dredging and reclamation will be expensive.

As a result of the increased focus on tourism, we continue to see more innovative and impressive designs coming up in the construction of the urban islands and coastline development. Such reclamation projects would allow for construction of hotels and housing facilities. This will involve many foreign investors, and hence, improve the region’s international recognition.

It's a great time for contractors, developers and consultants to come on board and help overcome construction challenges and build land on water.

4-6 December 2017 - Dubai, UAE

Come and find out how leading developers are addressing their challenges while constructing land on sea. Join government officials, developers, transport and infrastructure authorities and marine geotechnical consultants at the region’s leading event Island Development MENA Conference 2017 to discuss the upcoming opportunities in island development. The conference will address some the biggest challenges, requirements and best practices in design and construction of urban islands and coastline.