Today, Singapore is 721.5 km². Our land area has grown over 25% thanks to land reclamation projects. Over the most active reclamation period in 1965 to 2015, we have reclaimed 138km² (13,800 hectares).
(photo credits: Biblioasia)
The first reclamations started in 1822 shortly after Stamford Raffles landed in 1819. A hillock near today's Battery Road was used to fill the lowlying march at the south bank of Singapore River. This will become today's Boat Quay. Subsequent reclamations were carried out largely around the Central Business District, such as at Telok Ayer's Reclamation Scheme between 1879-1903. This expanded the constitution's coastline seawards. It required levelling parts of Mount Wallich and Mount Palmer to both improve transportation and provide landfill materials. It produced the New Harbour (renamed Keppel Harbour) for growing merchant ships in the region.
East Coast was our first major reclamation. It was a $613 million project that spanned 30 years over seven phases. It stretched from Tanjong Rhu, Telok Ayer Basin, the Marina, to Marine Parade, Katong, Bedok towards Changi. Fill materials were obtained from many places, including Siglap Plain and the hills in Bedok and Tampines. The Earth was cut by bucket-wheel excavators and transported by conveyor belt to a jetty off Bedok.
This is a similar technique used for most reclamations like the Pasir Ris, Punggol and Seletar areas, Coney Island, and West Coast - undertaken by the Housing Development Board (HDB). Jurong Town Corporation (JTC) covered reclamations on Singapore's west, mostly for industrial use. While the Maritime and Port Authority of Singapore (MPA), covered reclamation at the Port of Singapore, and Changi Airport, as early as 1960s. Notice the reduction in land elevation in the immediate vicinities of reclamation sites below.
(photo credits: Wang et al., 2015)
Land reclamation works typically starts with investigations on seabed condition, availability of fill materials, planned circumferences, and environmental impact (water and marine life mainly). Containment dykes made of sand and rock are built around the planned perimeter. Then, fill materials such as cut-hill soil, sand, clay etc are brought in to fill the area. Extra time is needed for the newly reclaimed land to settle before they can take the weight of large buildings.
Landfills are not reclamation per se, similarly expand land area. The old Lim Chu Kong dumping ground filled up a mangrove swamp. It closed in 1992. Our current landfills in Semakau and Pulau Sakeng are sea areas sectioned off by rock bunds. The waste generated by citizens and industries are treated at various plants and ultimately emptied here. The incinerated and non-incinerable waste are compacted into these spaces. After filling up, these areas will take 30 years to ‘settle’ before being used for permanent developments.
(photo credits: Straits Times)
With limited resources, our inland hills and sand dredged from surrounding seabeds started running out in the mid 1980s. The cost of foreign sand also skyrocketed from under $20/m2 in 1970s to $200/m2 in 1990s. Malaysia and Indonesia ultimately banned the export of sand to Singapore in 1997 and 2007 respectively. Therefore, we have to look into innovative ways to expand our land resources for our burgeoning needs.
Pulau Tekong's northwest project utilises Dutch empoldering technology. Dikes will stretch 10km around the island and stand at 7 metres above the polder. There after, the water in the basin will be drained to expose spaces that were previously low-lying seabeds. Estimates report this will be completed in 2022, and will contribute to 810 hectares, roughly 1% of Singapore's size.
This is a Young Geologist Project with Singapore Science Centre - 30 May 2020.
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