Session: 05-01-01 VLFS and New Concepts for Ocean Space Utilization

Paper Number: 132869

132869 - The Proposed Long Island Project in Singapore, Is There a More Sustainable Way? 

The Singapore Government recently announced plans for an 800-hectare reclamation on Long Island, south of East Coast Park.  The news set ablaze views across a wide spectrum of professionals. Although Singapore has reclaimed some 125 sq.km in the Straits of Singapore in past decades, the announcement came under the scrutiny from city planners, and the academia as well environmental scientists, and NGOs. The government is seeking inputs from those who have interests. The multi-year in-depth feasibility study will commence in 2024.

Several alternatives are possible. The government’s proposal is essentially an 800-hectare polder. Between the existing shoreline and the landward side of the reclaimed land a large strip serves as a catchment for freshwater fed by monsoon rain.

This paper proffers a solution using a series of gravity-based caisson (GBC) modules to form a lagoon separating the freshwater from the seawater. The GBCs are made using marine grade reinforced concrete with additives to prolong its durability . They can be manufactured offsite, launched and towed to its final position where it is aligned and ballasted with seawater. Some of the GBCs are designed to accommodate floating gates which when partially raised by deballasting allows excess water in the lagoon to be discharged into the sea. The top deck of the GBC is designed as a roadway for light vehicles.

Within the lagoon, floating platforms serve as foundations for residential and commercial buildings and for recreation parks or as dormitories for students in nearby institutions of higher learning. Transportation may be by ferries, flying taxis (such as the EH216-S) or buses similar to Vaporetto in Venice. Floating electric bicycles would be a personal mobility  option. There will not be any roads or drains to build or maintain. Floating bridges link key points to the mainland or the caisson roadways. Small barges  ply the lagoon to collect garbage and floating debris which are mechanically transferred to a larger barge outside the lagoon for transport to incinerators. There will not be any roads or drains to build or maintain. 

Modern ferries can clock up speeds in excess of 80 km/hr.  People living in the lagoon can travel to other parts of Singapore with such ferries. A floating terminal can be constructed alongside the barrage.

Why would a government consider this proposal when a major source of its income is leasing land? First, it is a greener option. Second, the capital outlay will be a fraction of the cost of land reclamation (estimated at SGD 6.4 billion). Third, the seaspace can also generate a source of revenue . At the end of the lease  the plot can be freed up in a short time frame (by the owner), freeing up the plot for another investor to lease. 

Maintenance of reclaim land is costly as challenges at the Kansai Airport and at Jumeirah Island have shown. Foundations for land based buildings take  more  money and time to complete. Buoyancy is a principle of physics independent of the soil properties below. The superstructure does not necessarily have to wait for the floating platform to complete. It can be prefabricated as the construction of the platform is in progress. 

Presenting Author: Soon Heng Lim The Society of Floating Solutions (Singapore)

Presenting Author Biography: Lim Soon Heng is a Fellow of the UK based Institute of Marine Engineering Science and Technology and served as a Board Member of the Professional Engineer Board in Singapore for multiple terms. Among other responsibilities as a board member he assessed, interviewed young engineers for accreditation and participated in hearings of alleged professional misconduct.

He has served in a number of technical and managerial positions over a span of 30 years in some of the leading shipyards in Singapore including the then Keppel Offshore and Marine (now a part of Seatrium Tuas Boulevard Yard.) He has considerable experience in the design, planning and construction of marine structures both in steel and concrete.

Lim founded The Society of Floating Solutions in Singapore. Since 2019, The Society has hosted a series of World Conference on Floating Solutions. The last one was held in Tokyo at the Nihon University and the next one WCFS 2024 will be held in Hong Kong at the Hong Kong University. The series focuses on space creation at sea to meet challenges on land scarcity, biodiversity and sustainability. The theme for the conference in Tokyo was “Floating Solutions for the Next SDGs (Sustainable Development Goals).”

In the face of rising sea levels coastal land and its ability to support livelihood is under threat. Lim sees the need to raise a higher level of awareness to policy makers, and urban planners, many of whom have limited knowledge of large floating structures, to think beyond land reclamation. He is also actively engaging post grad researchers exploring the impact of land reclamation in coastal areas of Indonesia, Philippines and Vietnam.

Lim participated in the OMAE 2023 event in Melbourne where he presented a thought-provoking concept on how to keep floating nuclear power plants safe in the context of global geopolitical tensions. It drew a lively discussion during the Q&A.

Authors:

Soon Heng Lim The Society of Floating Solutions (Singapore)