Palm Island in Dubai

Environmental Impacts

The construction of the Palm Islands and The World, for all Nakheel’s attempts to do otherwise, have had a clear and significant impact on the surrounding environment. It would be impossible to introduce a change of such magnitude to an established ecosystem and not anticipate any negative changes or reactions in the area’s wildlife and natural processes. The construction of the various islands off the coast of Dubai has resulted in changes in area wildlife, coastal erosion and alongshore sediment transport, and wave patterns. Sediment stirred up by construction has suffocated and injured local marine fauna and reduced the amount of sunlight filtered down to seashore vegetation. Variations in alongshore sediment transport have resulted in changes in erosion patterns along the UAE coast, which has also been exacerbated by altered wave patterns as the waters of the Gulf attempt to move around the new obstruction of the islands. Not surprisingly, Dubai’s megaprojects have become a favourite cause of environmentalists. Greenpeace has criticized the Palm Islands’ complete and utter lack of sustainability, and Mongabay.com, a site dedicated to rain forest conservation, has attacked Dubai’s artificial islands aggressively, stating that:

“significant changes in the maritime environment [of Dubai] are leaving a visual scar [. . .] As a result of the dredging and re depositing of sand for the construction of the islands, the typically crystalline waters of the gulf of Dubai have become severely clouded with silt. Construction activity is damaging the marine habitat, burying coral reefs, oyster beds and subterranean fields of sea grass, threatening local marine species as well as other species dependent on them for food. Oyster beds have been covered in as much as two inches of sediment, while above the water, beaches are eroding with the disruption of natural currents” (“Dubai’s artificial islands have high environmental cost”).

Despite other criticisms of Dubai, there is a significant amount of truth in Mongabay.com’s statements. The World Wildlife Fund made a similar announcement in 2006, declaring “UAE’s human pressure on global ecosystems (its ecological footprint) to be the highest in the world. The country is currently five times [in 2007] more unsustainable than any other country” (. It would be impossible to say that the effects of the islands have not been felt by the surrounding environment since the start of their construction, and will not continue to be felt into the future.

So in order to properly manage their shorelines and effects, Dubai relies on its very comprehensive coastal monitoring programme. Established in 1997, the Dubai coastal monitoring programme began studying the baseline bathymetric and topographic survey of the Jumeirah coastline. However, since then better technology and more additional data was able to be collected, including remote video monitoring of Dubai beaches, sediment sampling and analysis, near shore directional wave and current recordings and intensive measurement exercises at selected locations using Acoustic Doppler Current Profiler (ADCP) equipment. Below is a breakdown of those methodologies of monitoring and what they survey and measure.

Bathymetric and Topographic Surveys

First, the Dubai coastal zone has been divided into different regions for more organized monitoring. The frequency of the surveys in a region is determined by the environmental risks that the particular region poses. For instance, areas more affected by coastal erosion or inundation are monitored more than those that are less likely to not be affected. The bathymetric survey covers a 500m wide band along the entire coastline with survey lines that run perpendicular to the coast, 25 m apart from each other. A dual frequency echo sounder and differential GPS are used to collect data along these lines. Some of the data obtained deal with sediment budget and transport systems. Topographic surveys are carried out using a pre-defined set of profiles that run perpendicular to the shoreline down to mean water level +1.13m DMD (Dubai Municipality Datum). Scatter point surveys are also completed at 10 locations along the coast to produce a contour map of the beach. Data is also collected by Real-Time Kinematic Geographical Positioning Systems (RTK GPS).
Near shore Wave Measurements

1,200 kHz ADCPs with pressure sensor have been stationed at a near shore position north of Jebel Ali Port in 6 m water depth and off the Jumeirah Public Beaches, providing directional wave information in the region of the most immediate interest to the Municipality. “The instrument measures currents throughout the water column using the return echo of an acoustic signal transmitted by the instrument. The instrument not only provides valuable information to the Municipality, but also to the general public via internet. A pressure sensor was also installed behind the northern arm of the T breakwater to provide information on water levels within the sheltered embayment. Variations in water depth (pressure head) induce corresponding resistivity readings in a piezo-electric device in the instrument. The value of resistance measured is proportional to the depth of water. The data reveals a lot about coastal hydrodynamic processes occurring along the coast, to calibrate or verify hydrodynamic models as well as to assess bather safety concerns.”

Video Monitoring

On the thirty-fourth floor of the Burj Al Arab hotel, which is located offshore on the Dubai coastline are two installed video cameras that take time-lapse snapshots of beaches using GPS corrected control points. Once the images are processed, and control points are established, a representative water line is determined. So far data from the video cameras have just been used for verification purposes to measure the accuracy of extracted water levels from images to real survey data. However, now these images will be used in designing profile dynamics and exploring bar dynamics and the extraction of near shore current patterns using cross-image correlation.

Meteorological Data

There is a a meteorological station at Jumeirah Open Beach that helps provide information on wind speed and direction, barometric pressure and air temperature. The station is run by EmuDome Dubai Environmental Monitoring System (EDEMS), a custom built software package. EDEMS allows easy access to transfer of this useful information between a client and project team via internet.

Sediment Sampling

Sediment Samples are collected along all of Dubai’s beaches and near shore zone and are analyzed according to grain size, fall velocity, allowing scientists to make many conclusions about the coastline evolution, sediment transport and morphological models set up for the region.

Coastal Monitoring of the Palm Island Area

The construction of the artificial islands have altered the Dubai coastline. For instance, the construction of Palm Jumeirah has caused the coastline in the southwest shadow of the island to grow very quickly. Wave models reveal that the northerly waves are removed from the near shore wave regime at Mina Al Seyahi through the existence of the Palm island. With this removal, north-eastward transport rate is greater and as a result, there is a build-up of the coastline. However, on the other side of Palm island, the reverse occurred. The coastline here had been retreating because the harbour  blocked movements of sediments travelling from the southwest and the north easterly transport had gradually eroded the beach. With the removal of waves from the north-west by the construction of Palm Island, Northerly waves “become” relatively stronger. Thus, the reverse effect is obtained here, resulting in lots of erosion (an illustration and more basic analysis of this phenomenon can be found on the Construction of Palm Islands page).