Dubai’s extreme reclamations

Rob de Jong1, Peter van Gelderen2, Mark Lindo3, Jack Fernandez4

Abstract: This paper will give an overview of the reclamations as executed and in execution during the last four years in Dubai. It will also place these reclamations in perspective to the large reclamations of the past with respect to fill volumes to show how extreme Dubai’s reclamations really are. Moreover, the intended land use and the design philosophy of the Palm Jumeirah, The Palm Jebel Ali and The World, three of Dubai’s large reclamations that are (or have been) executed, will be discussed including the execution strategies applied to create them. Water depth and protection of the reclamation during the construction phase will turn out to be key elements. Keywords: Reclamation, Dubai, Palm Jumeirah, Palm Jebel Ali, The World, history 1Project Engineer Van Oord, T +31104478444, F +31104478100, rjo@vanoord.com, www.vanoord.com 2Project Engineer Van Oord, T+31104478444, F +31104478100, pge@vanoord.com, www.vanoord.com 3Head Eng. Department Van Oord, T+31104478444, F +31104478100, mli@vanoord.com, www.vanoord.com4Director Marine Engineering Nakheel, T+97143903333, F+9713680506, jack.f@nakheel.ae, www.nakheel.ae

1 INTRODUCTION The last century the scale of the land reclamations has increased tremendously, especially the last decades with large reclamations in Hong-Kong (Chek Lap Kok, Penny’s Bay), Malaysia (Pelepas) and Singapore (Jurong Island, Tuas View, etc). These reclamations were mainly used for industrial and infrastructural activities or theme parks. Their shape was mostly rectangular and they were surrounded by rubble mound or concrete element slope protections. The last 4 years the most extreme reclamations are being constructed in Dubai, such as the Palm Jumeirah, The Palm Jebel Ali and The World, and there is more to come. These reclamations are not used to expand industrial and infrastructural activities, but for future housing and recreation. For this reason traditional slope protections and rectangular shaped reclamations are no longer desired. It is the intention to create as much beach front as possible. This results in other concepts of protection against waves such as offshore breakwaters surrounding the reclamations and it also gives the opportunity for innovative island shapes. This paper will place the current reclamations in Dubai in perspective to the large reclamations of the past with respect to fill volumes. Moreover, the intended land use and the design philosophy of the Palm Jumeirah, The Palm Jebel Ali and The World will be discussed including the execution strategies applied to create them. The available water depth and protection of the reclamation during the construction phase will turn out to be key elements.

2 HISTORIC REVIEW OF LARGE RECLAMATIONS

2.1 River reclamations In the past a lot of reclamation projects varying in size have been executed. The reclamation works in the prehistory were mainly executed in rivers. Already in 18,420 B.C. the Egyptian King Ptah became the first king of Egypt and was known as the “Creator God”. He undertook great works of land reclamation and dyking thus explaining Egypt's nickname, "The Raised Land". Another example of early land reclamations in river beddings was executed in the Chinese Yangtze River in the Three Kingdoms period (220-280). The newly reclaimed land was used for farming, especially rice fields.

2.2 Estuary reclamations Later, extensive land reclamations have been carried out in estuaries, for example in the Shannon estuary in western Ireland, possible beginning as far back as the tenth or eleventh century. Here the tidal range was used to drain the water from the reclaimed land. These land reclamation projects were mainly used for agriculture as well.

2.3 Polder reclamations The next step in land reclamation originates from the seventeenth century and was made in the Netherlands. In those days the western part of the Netherlands flooded regularly. Storm surges resulted in large swamp lakes that became bigger and bigger in what is currently called the province of “Noord Holland”. On top of this, a large lagoon with open connection to the sea, the “Zuiderzee”, penetrated deep into the center of the Netherlands causing regular floods around its perimeter. In the seventeenth century, land was mainly used for agriculture as the industrial revolution would take place only two centuries later. Protection of the people and creation of land for housing and agriculture became the incentive for the “poldering” of the first lakes starting at around 1600. The land was reclaimed by surrounding the area with a dyke, however this time followed by pumping (!) out the water form this enclosed area. After reclamation the water levels were controlled in a genius way by a whole system of small channels (“boezems”) and dykes which finally deposited their water in rivers and seas. The windmills and later the (steam driven) pumping engines were essential tools to pump the water out of the reclaimed area which currently result in dry land at levels down to approximately 6.75m under the mean sea level.

Fig. 1: Large polders reclaimed in the twentieth century

Fig. 2: The polder system

In the twentieth century another 150,000 hectares of land was reclaimed from the sea, by closing the “Zuiderzee” with a big dam, the “Afsluitdijk”, in combination with the creation of huge new polders: Wieringermeer (1930), Noordoostpolder (1942), East Flevoland (1957) and South Flevoland (1968).

2.4 The Netherlands - Maasvlakte The polder reclamations were followed by another type of reclamation, being port extensions. It started in the Netherlands with the extension of the port of Rotterdam. In the 1950’s the demand for storage space in harbours increased enormously, especially the requirements by the oil industry. Moreover, the size of the vessels increased rapidly including their draught requiring deeper access channels. To maintain their leading position relative to other West-European ports, Rotterdam had to extend its port and deepen its access channel. The first stage of this expansion, called “Europoort” (Port of Europe) started in 1958. A second stage extending into the sea is called “Maasvlakte” and was started of in 1964. This time the polder principle could not be applied because handling of the cargo required quay walls etc. above water level and with polders this is impossible without the use of big locks which would be too time consuming for the sea going vessels. To reclaim the 3,000 hectares of land up to well above high water level, a quantity of around 450 million m3 of fill was therefore required. This material was mainly reclaimed from the harbour basins that had to be deepened anyway by means of stationary equipment such as Cutter Suction Dredgers (CSD’s) and Suction Dredgers (SD’s). Trailing Suction Hopper Dredgers (TSHD’s) were only used to supply a small portion of the required material such as gravel for the revetments from the seabed of the North Sea and to move some material that was reclaimed from the deepened access channel extending into the sea. The hopper capacity of the largest hoppers used here was order 10,000 m3. The Maasvlakte was completed by 1974, but an additional expansion of 2,000 hectares equaling about 300 million m3 of fill will probably start soon.

Fig. 3: The Maasvlakte (The Netherlands)

2.5 Hong kong – Chek Lap Kok Airport The following big reclamation project has been the Chek Lap Kok Airport in Hong Kong. This was the first extreme reclamation (940 hectares) that was constructed by means of mainly TSHD’s. It took place between 1993 and 1997 and required approximately 180 million m3 of fill (approximately 75 million m3 of sand and 105 million m3 of rock fill). The rectangular shape of the reclamation was dictated by its function: hosting airport runways. The end use of this reclamation as an airport in combination with the soft subsoil resulted in a new challenge for the reclaimers: controlling settlements. For this reason 160million m3 of poor material had to be removed before starting the reclamation.

Fig. 4: Chek Lap Kok Airport (Hong Kong)

2.6 Hong kong – Penny’s Bay Up till than the large reclamations were made for agricultural and industrial (and logistical) purposes. The reclamation of Penny’s Bay was the first reclamation for leisure. It hosts Disneyland Hong Kong. Its shape is directed by the shape of the bay and further it is rather square as this gives the most efficient land use. The reclamation of this 200 hectare area required approximately 70 million m3 of fill and was started in 2000 and finished 2002. Again settlement control was a big challenge on this project. This is confirmed by the fact that first 43 million m3 of soft fill had to be removed before the reclamation could be started. The maximum hopper size had again increased, this time to approximately 21,500 m3.

Fig. 5: Penny’s Bay Disneyland (Honk Kong)

2.7 Malaysia - Port of Tanjung Pelepas The first stage of the Pelabuhan Tanjung Pelepas project in Malaysia was executed in between Chek Lap Kok and Penny’s Bay from July 1997 to July 2000. The reclaimed area is utilized as container terminal to compete with the large container terminals in Singapore and involved the removal of order 21 million m3 soil (mostly to create a 9 kilometer long access channel) and supply of order 18 million m3 of suitable fill and the dredging of the access channel. The reclamation area was a swampy area with mangroves which had to be removed before commencement of the reclamation. For this project the big challenge again was control of the settlements and the stability of the subsoil and reclamation fill. Due to scaling-up of the container vessels and favorable economic growth, extension was already required after several years. In this phase 2 the present reclamation area was enlarged to total 560 hectares and the access channel was widened. The works in this phase 2 included the removal of more than 40 million m3 of mud and clay, the reclamation of some 35 million m3 of sand, the compaction of the reclaimed sand and subsoil consolidation. Pelepas phase 2 started in 2002 and finished in 2004. The maximum hopper size utilized on this project was further increased to over 33,000 m3.

Fig. 6: Port of Tanjung Pelepas (Malaysia)

2.8 Singapore In the late 1990’s the new center for the world’s dredging industry was Singapore. Large reclamations were conducted in several stages mainly to extend the capacity of Singapore’s ports. The big challenge in these projects was the quantity totaling two billion m3 of fill material as presented in table 1 which mainly has to be brought in from the neighboring countries Indonesia and Malaysia as this material is not available in Singapore’s own territorial waters. As from around 1993 the reclamation works in Singapore gradually started and were suspended in 2002 as obtaining licenses to borrow from Indonesia and Malaysia became a problem. For these projects the latest jumbo hoppers were developed with hopper capacities up to order 35,000 m3 which enabled an economically feasible price for reclamation fill despite the relatively large sailing distances between the borrow areas and the reclamation sites.

Fig. 7: Singapore’s reclamations

Table 1: Projected and installed fill quantities Singapore (status as of 1 Augustus 2005)

Sand fill quantities Location No. Sand/gravel fill Start date works Projected [m3] Installed

- Pasir Panjang Sept 1993 30,000,000 100% - Jurong Island July 1996 102,000,000 100% 1 Jurong 3B January 1999 220,000,000 90% 2 Jurong 4 and Tuas extension B July 2000 500,000,000 45% 3 Tuas extension A July 2000 250,000,000 65% 4 Pungol June 1999 2,000,000 100% 5 Changi September 1994 105,000,000 100% 6 Pulan Ubin / Tekong Ubin cancelled Included in 7 n/a 7 Pulau Tekong November 2000 235,000,000 40% 8 Changi Future 80,000,000 0% 9 East Coast Future 250,000,000 0% 10 South Islands Future 100,000,000 0% 11 Live firing range Future 200,000,000 0% Grand total - 2,074,000,000 44%

3 UNITED ARAB EMIRATES – DUBAI’S RECLAMATIONS With the construction of the Palm Jumeirah in 2001, the location of the world’s most extreme reclamations started to shifted to the Middle East. The last 4 years the most extreme reclamations are being constructed in Dubai for it’s prime developer Nakheel, such as the Palm Jumeirah, The Palm Jebel Ali, Deira Corniche and The World, and there is more to come like The Palm Deira and Dubai Waterfront. The total projected fill volume of these projects combined is unsurpassed and over a stoning 2.4 billion m3 as presented in Table 2. A second challenge is the supply of the enormous quantity of rock required for all the projects. As all projects are built fast track and mostly simultaneously. Weekly supply rates of up to 400,000 ton are therefore no exception. All the rock originates from the Siji and Ras Al Khaimah area in the United Arab Emirates and has to be quarried and transported either by truck or by barge to the various construction sites.

10. 11.

4. 2.

1. 5.

7. 12. 9. 6. 8. 3.

Fig. 8: Overview extreme reclamations Dubai

Table 2: Projected and installed fill and rock quantities Dubai (status as of 1 Augustus 2005)

Sand fill quantities Rock quantities Contractor Sand fill

Start date

works Projected

[m3] Installed Projected

[mton] Installed

1 Palm Jumeirah Van Oord Nov. 2001

105,000,000 100% 9,000,000 100%

2 Palm Jebel Ali Jan de Nul May 2002

125,000,000 80% 10,000,000 80%

3 Logo Islands Van Oord Jun. 2003

4,500,000 100% 1,000,000 100%

4 The World Van Oord Oct. 2003

300,000,000 75% 32,000,000 30%

5 Dubai Maritime City / Port Rashid Expansion

Van Oord Nov. 2003

40,000,000 25% 5,000,000 50%

6 Dubai Beach Development

Van Oord Dec. 2003

3,500,000 90% 500,000 100%

7 Deira Corniche Van Oord Dec. 2003

230,000,000 20% 7,000,000 0%

8 Mina Seyahi Marina Van Oord Apr. 2004

500,000 90% 1,100,000 95%

9 Glass Palace Island Van Oord Oct. 2004

2,500,000 100% 800,000 95%

10 Palm Deira -

- 1,200,000,000 0% 80,000,000 0%

11 Dubai Waterfront -

- 400,000,000 0% 16,000,000 0%

12 Expansion of Port Jebel Ali

- - 24,000,000 0% 5,000,000 0%

Grand total - 2,435,000,000 20% 167,400,000 19% These reclamations are not used to expand industrial and infrastructural activities, but for future housing and recreation such as hotels. For this reason traditional slope protections and rectangular shaped reclamations are no longer desired. It is the intention to create as much beach front as possible. This results in other concepts of protection against waves such as breakwaters and submerged berms surrounding the reclamations and also gives the opportunity for innovative island shapes. On top of the sourcing and supply of these enormous quantities of sand fill and rock, the big challenge in these projects is the combination of slender shaped sand cross sections and relatively short execution periods. As a result of the tight schedules the sand reclamation works can not wait till the construction of the protective rock breakwaters are finished. Therefore, the relative slender reclamations are exposed to offshore waves during the construction which is a considerable risk in the Arabian Gulf where on average one extreme storm (Hs offshore >3.5m) per year takes place. Special construction strategies have to be applied to minimize damage during these events in the construction period as will be explained in Section 4.

4 OVERVIEW EXTREME RECLAMATIONS DUBAI

4.1 Palm Jumeirah It all started off with the construction of the Palm Jumeirah in 2001. The palm tree shaped island itself consists of sand only and was build by a Van Oord ACZ - Ballast Ham Dredging joint venture, the two companies which are nowadays merged into Van Oord. The crescent shaped breakwater around it, designed by Royal Haskoning and constructed by Archirodon Overseas, is armoured by rock at the outside which protects the palm from offshore waves and has beaches at the inside. This innovative island design can not only be clearly identified as a palm tree from out of space, but also doubles Dubai’s coastline by adding 65 kilometer of beachfront which creates an attractive habitat. The dimensions of this Palm Island are impressive. Dimensions of the palm itself: 4 km by 4km. The crescent breakwater extends 5 km offshore and is 5.5 km wide with a total length of 11km. The reclaimed surface area is about 650ha and the installed sand volume is about 105 million m3. In addition to this 9 million ton of rock was installed to protect the island. The fronds of the palm are designated for villas, whereas the trunk of the palm will host restaurants, boutique shops, marinas and shoreline apartments. The land at the inside of the crescent breakwater will be occupied by hotels.

Fig. 9: Sandfilling for the Palm Jumeirah

The area under consideration has water depths ranging between 8-10m below Jebel Ali Chart Datum (tidal range is approximately CD+0.5m to CD+1.5m) and the area has an almost horizontal to very mild foreshore. This draught limitation enforced the use of relatively small hopper dredgers with typical hopper capacities of 3,500-8,000 m3 of which up to 8 were working on the palm at the same time. In addition cutter dredgers were used mainly for the fill underneath the rock protection. The reclamation and rock works commenced in the summer of 2001 and had to be finished by the end of 2003. Because of this tight time schedule the sand supply for the palm itself could not wait for the protecting crescent breakwater to be finished. Therefore, the relative slender palm fronds (approximately 90 m wide) would be exposed to offshore waves during the construction which is a considerable risk in the Arabian Gulf with its Shamal storms. Therefore an optimal execution schedule in terms of maximum speed of construction and minimal risks (of damage) was developed cleverly scheduling the works taking into account and combining the increasing sheltering effect of the crescent under construction, the relevant sediment transport processes and the vessel characteristics and movements. During the first winter Van Oord only dumped sand up to a level of approximately CD-4m. Although hardly protected by the breakwater of which the construction had just started, the waves had little effect on the installed sand because it was placed far enough under the water surface. In this way a considerable quantity of sand could already be installed with minimum risk on sand losses. By keeping access channels open through the spine of the palm tree, all sections were kept accessible for rainbowing such that more expensive pumping ashore could be avoided. At the same time sailing distances were kept minimal this way as the hopper dredgers did not have to go all the way around the Palm. The hoppers were supplied with daily survey updates to guaranty safe navigation through the reclamation area. In the second winter the construction of the breakwater had progressed to such an extent that protection was available. The sand was brought above water in the protected areas only, carefully following the progress of the breakwater. The Palm grew quickly as the bulk of the underwater body was already in place. The works were therefore finished in time and the approach has turned out to be very successful.

Fig. 10: The construction sequence of the Palm Jumeirah

4.2 Palm Jebel Ali The construction of the second Palm Tree shaped island was announced in 2001. The construction started May 2002. The crescent shaped breakwater design originates once again from Royal Haskoning. The physical execution of all works is presently undertaken by Jan De Nul of Belgium and finished for about 80%. This project again means an impressive increase in Dubai’s beachfront with 75 km. The dimensions of this second Palm Island are even bigger. The Palm tree itself is only slightly bigger: 5 by 4 km. The offset of the crescent from the tips of the frond is however increased in this design to make room for some 2,000 water homes constructed on piles. This means the crescent breakwater extends 7 km offshore and is 7 km wide with a total length of 16 km. The total reclaimed surface area is some 650 ha with a deposited sand quantity of 125 million m3. In addition to this some 10 million ton of rock was placed to protect the island against the elements of nature.

Fig. 11: Artist impression of Palm Jumeirah (left) and Palm Jebel Ali (right)

The land use of Palm Jebel Ali will focus on housing, shoreline developments, hotel & resorts (4 and 5 star), golf courses and marinas. The crown, with 17 fronds in total, will feature series of shoreline villas, where as at the top end of the crown very luxurious properties are to be developed. It is expected that some 130,000 people will live on Palm Jebel Ali in due course. The water depth in this location is ranging between 3 to 4 meter at the shore to 10m at the bulge (all below Jebel Ali Chart Datum). The importation of sand would therefore be restricted to barges and small to medium capacity trailer suction hopper dredgers. To avoid this, an access channel was dredged connecting the existing Jebel Ali Port Access Channel with the Palm Jebel Ali. The dredged material was loaded in barges and deposited on the seabed in the future Palm land area. Since Jan De Nul at the same time also secured a project to deepen the Jebel Ali Port and Access Channel, part of the material originating from that project (the suitable soils) was also used to construct the future Palm. Within the Crescent arched access channels were dredged to make the Crest

accessible to large trailer suction hopper dredgers. In this way these could supply the sand from the inside of the Crest, always having shelter from the reclamation and the breakwater, all year around. In brief one can summarize the following stages: 1. Dredging Palm access channels, Jebel Ali Port access channel and basin with a Cutter dredger, load and

transport the dredged material in barges and subsequently dumping the material in the future Palm to a level of CD-3m to CD-4m.

2. Dredging access channels within the Palm and pumping the dredged material through a pipeline and spray it onto the earlier dumped sand deposits.

3. Import sand with Trailer Suction Hopper Dredger from offshore and rainbow or discharge the material through pipelines and form the final reclamation area.

Fig. 12: Sandfilling for the Palm Jebel Ali

To protect the Palm Tree from the elements of nature the idea was that the breakwater Contractor would, concurrent with the progress of the sand fill, construct the breakwater and protect the reclamation from wave attack. Due to various reasons the first two Contractors assigned to this task did not manage to construct the breakwater on program. End 2003 the Client asked Jan De Nul to take over the construction of the Breakwater, which at that stage had seen only some underwater dumping and attempts to place armour rock against it. The contract to take over the breakwater was awarded in March 2004 and works started immediately to remedy already placed rock. By the winter of 2004 the North West side of the Palm was protected. Because of the construction method, working from the inside of the breakwater and always having shelter from placed rock, it was possible to continue working in the winter period and by the end of 2005 the breakwater construction is in its final stage.

Fig. 13: Rock installation for the Palm Jebel Ali

Fig. 14: The construction sequence of the Palm Jebel Ali

4.3 The World After Palm Jumeirah and Palm Jebel Ali Dubai was ready for the next step in large sized reclamation projects: The World. The World is located in the coastal waters of Dubai 4 km of the original coastline. Initially The World comprised the construction of order 10 islands, together forming the shape of the continents of the globe. To protect these islands from waves, a series of breakwaters around the islands was designed by Royal Haskoning. In this original scope the dimensions of The World were 4 km by 6 km and comprised a total reclaimed volume of 117 million m3 sand. Right before commencing the reclamation works on 10 October 2003 the scope of The World project was increased. The 10 islands were divided into smaller islands totaling up to a number of 300 islands. Also the dimensions increased significantly to 7 km by 9 km. With this increase in scale the total volume of sand to be reclaimed became 300 million m3. The scope of work also includes the construction of various types of breakwaters with a total length of 25 km, including the longest continues breakwater (13 km) ever built, incorporating a total of 32 million ton of rock. Both the rock works and the sand fill are conducted by Van Oord. On completion of the World, scheduled for May 2007, the Dubai land area will be increased with 940 hectares and the Dubai coastline will be lengthened by 235 km. As the project developer of The World, Nakheel, says: “The Palm puts Dubai on the map, The World puts the map on Dubai”.

Fig. 15: Artist impression of The World and first island ready to be inhabited

The World is a collection of private islands which gives individuals and investors the opportunity to build anything they desire, from the perfect island home to exotic resorts, golf courses or corporate retreats. No connection to the main land will be present. An overall infrastructure like marinas, water taxis, safe navigation systems and communication connections will be taken care of by the project developer Nakheel.

Fig. 16: Sandfilling for The World

The area under consideration has water depths ranging from CD-12m to CD-18m. The foreshore, as for the Palms, has a very mild slope. Since the water depth is somewhat larger than for Palms it was economically attractive to use large jumbo hopper dredgers for the reclamation of the islands. To bring the sand to the final level of CD+3m, a so called train of hoppers was planned. The hopper sequence would be: 1) large jumbo hopper dredgers would dump the sand to a level of around CD-10.5m; 2) medium sized hopper dredgers would further dump the sand to a level of around CD-7.5m; 3) small sized hopper dredgers dump the sand up to a level of CD-5.0m; 4) large jumbo hopper dredgers would rainbow the islands to a level of CD+3.0m. In this sequence large jumbo hopper dredgers have typical capacities of 14,000 – 30,000 m3, medium sized hopper dredgers 6,500 – 14,000 m3 and small sized hopper dredgers 2,500 – 6,500 m3. To date a maximum of 13 hopper dredgers have been working on The World at the same time. To limit the execution time to a reasonable period and in view of the increased reclamation quantities the Palm Jumeirah scenario (first protection by the breakwater, after that building the sand up to the final level) could not be followed. Another execution strategy had to be found. Initially the execution strategy was to create strings of sand across the continents up to a level of CD+3m. This is called phase 1. The size of the strings was calculated according to a volume balance in such a way that in phase 2 of the project the islands could be created from these strings by Cutter Suction Dredgers. Due to delayed rock supply more sand filling in unprotected water had to be carried out than originally anticipated. By first constructing East-West-orientated strings in the north of North America and the north of Europe and Asia, the reclamation progress became independent of the progress in the rock breakwater works. To reduce the quantity of cuttered sand in phase 2, it was also decided to change the execution strategy in phase 1 from creating strings into directly creating the individual islands as good as possible with Hopper Dredgers in phase 1. Due to the protective sand bunds in the north this became possible. These islands have a simple shape and no high accuracy (in contour lines) can be achieved. In phase 2 these islands will still have to be shaped to their final layout. This is visualized in Figure 17.

Fig. 17: Phase 1 rainbowed island (left) and phase 2 shaped island with CSD (right)

In Figure 18 the protective sand bunds and the individual islands created by hopper dredgers are clearly visible.

)

Jul 2005, Shamal Breakwater (front), Protective string of North-

America (top right) and Asia (top left) tion sequence of The World

Tthasw Ttod FPthlom

Fig. 18: The construc

Jan 2005, Protective string of North-America (front) and Asia(b k)

he protective strings in e northern hemisphere well construction of pest direction in Antarct

he behavior of the prot the protective strings

ependent on the progres

or the breakwater consontoons. With a total coe works. The rock is daded on the SSDV’s aeans of wheel loaders a

Nov 2004, Protective string of North-America (right) and Asia (left) (back

North-America / Greenland and Europe / Asia will only provide sheltered conditions in of The World. To enable rainbowing of islands in phase 1 on the southern hemisphere rotective strings also started in a north-south direction in South-America and in an east-ica.

ective strings is closely monitored for obvious reasons. Whether or not sand suppletion is required in due time to guarantee that they will continue to fulfill their function is s in the construction of the breakwaters.

truction Van Oord makes use of Side Stone Dumping Vessels (SSDV) and Mooring nstruction time of 3 years, an average of 200,000 ton rock per week has to be placed in elivered to site on 10,000 ton rock barges. From these rock barges the rock is either nd from there dumped in the breakwaters or dumped directly into the breakwater by nd excavators.

Fig. 19: Rock installation for The World

5 CONCLUSION

From the historic overview presented in this paper and summarized in Table 3, various trends in the land reclamations can be discovered.

1. Reclamations are more and more executed in locations with exposure to waves. This influences not only the permanent protection required, but also means that the execution sequence should be determined with great care in order to prevent excessive damage during construction. The methods applied for the Palm Jumeirah, Palm Jebel Ali and The World show that either the reclamation should carefully follow the construction of the protective rock breakwater (Palm Jumeirah, Palm Jebel Ali) or sand bunds should be created which can handle the reshaping which occurs during the construction period (The World).

2. The land use of the extreme reclamations has changed from agriculture to ports and from ports to tourism. The intended land use has a great impact on the type of reclamations and the protection of these reclamations. The polder type reclamation with very favorable “surface area / reclamation volume”-ratios were no longer possible for port construction as ports required their quays to be accessible without locks. The islands constructed for tourism introduced innovative shapes and rock revetments being replaced by offshore breakwaters in order to create as much beach front as possible.

3. During the last decades the size of the largest hopper dredgers has increased a factor 3.5, making the ever increasing reclamations possible in feasible time frames and for feasible cost.

4. The projected sand volumes for all the reclamation projects in Dubai surpass all reclamations in the world so far.

Table 3: Survey extreme reclamations

Period Location Land use Type of reclamation &

protection

Surface area [ha]

Volume of fill

[million m3]

Max. TSHD

size [hopper

m3] River

reclamations From

18,420 B.C. River

beddings Agriculture Dykes & river

level variation - - -

Estuary reclamations

From 10th century

Estuaries Agriculture Dykes & tidal range

-

- -

Dutch Polders From 17th century

Lakes Agriculture, Housing

Dykes & mechanical pumping

150,000 - -

Rotterdam Port (Europoort & Maasvlakte 1)

1958-1974 Ports at sea fronts

Port Square sand fill &

revetments

3,000 450 10,000

Hong Kong (Chek Lap Kok

& Penny’s Bay)

1993-1997 &

2000-2002

Semi-open & open sea

Airport & Theme Park

Square sand fill &

revetments + soil

improvement

1050 250 (+removal

43)

21,500

Malasya (Tanjung

Pelepas Phase 1 & 2)

1997-2000 &

2002-2004

Semi-open sea

Port Square sand fill &

revetments + soil

improvement

560 53 (+removal

61)

33,500

Singapore 1997-ongoing

(suspended)

Open sea Port Square sand fill &

revetments

10,000 1,907 33,500

Dubai 2001-ongoing

Open sea Tourism Slender shaped Sand

fill & Separate

breakwaters

20,000 2,435 33,500