Land Reclamation for 'Pearl Necklace': 9 Islands in the Gulf of Thailand, Is It Worth?

"...‘Land Reclamation’ has become a popular method by many countries worldwide to expand urban areas, create new residential spaces, prepare for economic development, and tackle flooding issues caused by climate change..."

Land Reclamation for 'Pearl Necklace': 9 Islands in the Gulf of Thailand – A New City and Flood Protection for Bangkok, Is It Worth It?

While such projects open new doors for urban development, they also bring significant environmental challenges that cannot be overlooked.

Over the past two decades, Land Reclamation  for artificial islands or coastal expansion has grown substantially. Reclaimed land now totals over 2,500 square kilometers, an area roughly the size of Phra Nakhon Si Ayutthaya Province.

In Thailand, around the end of August, Mr. Thaksin Shinawatra mentioned the "Coastal Reclamation Project" for Bang Khun Thian and Pak Nam in the context of urban development and expansion in Bangkok. Speaking at the Vision for Thailand 2024 event on the 22nd of August 2024 about the objectives to increase land availability, reduce congestion, create a green, modern city exclusively for electric trains, and establish flood prevention measures.

"I’ve talked about this idea for a long time but haven’t been implemented yet—reclaiming land in Bang Khun Thian and Pak Nam to create more space, ease Bangkok’s congestion, and establish a green, modern city served only by electric trains with connected rail systems. This project would also contribute to flood prevention in Bangkok. We must start preparing flood defenses today. Coastal reclamation will help in sustainable urban development, aiming to build infrastructure that aligns with economic growth and improves the quality of life for the people," Thaksin stated.

Mr.Thaksin Shinawatra

The " Bang Khun Thian Coastal Reclamation Project" will be a mega-investment project involving the construction in the sea. Initially, there might be the creation of nine islands, each with seawalls and floodgates. The first island would be built along the Bang Khun Thian coastline, with other islands extending towards Chonburi, covering a total distance of approximately 100 to 150 kilometers across the gulf.

Each island, designed to serve as a connection point for the seawalls, span around 50 square kilometers and be located about one kilometer from the shore. A road network would link the islands to the mainland for convenient access. The project has been named the "Pearl Necklace of the Gulf of Thailand" due to the islands' appearance, resembling pearls strung together. To manage tidal flows, floodgates would be constructed between the islands. This concept is used in other countries, such as the Netherlands.

Mr. Plodprasop Suraswadi, former Deputy Prime Minister and Chairman of the Environment Policy Committee, Pheu Thai Party, discussed the concept of the Bang Khun Thian coastal reclamation project aimed at creating a new city and addressing flood issues. He emphasized the need to push forward with the project to prepare for future flooding problems and this plan has long been in the works and studied by Pheu Thai Party.

This is a response to the effects of global warming, which has led to increased polar ice melting. This issue has been discussed at the United Nations for years, with rising sea levels and many areas being submerged. The Gulf of Thailand is expected to be impacted.

Initial models predict that, in the worst-case scenario of global warming, rising sea levels in the Gulf of Thailand due to the melting of polar ice could increase by as much as 5 to 6 meters. This would result in flooding of 16,000 square kilometers of areas in central Thailand. Parts of the Gulf of Thailand would reach as far inland as Lopburi, Saraburi in the north, and Uthai Thani. Areas like Bangkok, Nonthaburi, Pathum Thani, Singburi, Ang Thong, Phra Nakhon Si Ayutthaya, Prachinburi, parts of Chonburi, Samut Sakhon, Samut Songkhram, and parts of Phetchaburi would also disappear.

“Given this issue, I fear it will escalate. We have to determine what we believe in. If Thailand chooses not to believe, that’s fine. But if we do believe, we must find ways to prevent it. There are many options for prevention that we need to consider," said Plodprasop.

Plodprasop discussed solutions for flood prevention from rising sea levels by 5 to 6 meters, which could flood 16,000 square kilometers of central Thailand which are Option 1: Constructing flood barriers. This way would serve as a short-term solution, lasting 2 to 5 years, by reinforcing flood barriers or building new ones along the Chao Phraya, Tha Chin, and Mae Klong rivers along with sealing any breaches to ensure full functionality of the barriers, which must be at the same level.

Option 2: Raising roads. Since 16,000 square kilometers would be submerged such as Phetkasem and Sukhumvit. Floodgates would be installed in key canals that connect to the sea. Large floodgates would need to be built along the four major rivers: the Chao Phraya, Tha Chin, Mae Klong, and Bang Pakong. This would require a massive financial investment.

"Raising roads is not an easy task, for example, Rama 2 Road, which has been under construction for decades, is still not finished. If we were to raise two major roads from Phetchaburi to Chonburi to combat flooding, it would create even more chaos. And we still lose the land along the coastline from the road to the sea." Plodprasop remarked.

Option 3: constructing sea barriers. While technically feasible, this would require enormous financial resources. An interesting idea is creating islands in the current bay area by reclaiming land.

Plodprasop further explained that once the sea is reclaimed to create islands, each island would need careful planning for its use and purpose. There are varying factors: some islands might be designated as new ports to replace existing ones in Bangkok, Samut Sakhon, and Samut Songkhram. Other islands could host fishery industries or be developed into yacht harbors. An island near Chonburi could even be used to build a new airport.

"Currently, we have many technologies for island construction, and many countries have already succeeded it, such as Japan, China and the Middle East. Many countries are experienced. As for the islands built by private investors, they may receive concessions. To think about it, this project will be the largest and most challenging investment initiative, but it is necessary because if we don’t act quickly, we will be submerged." said Plodprasop.

Plodprasop continued that if the government adopts this idea, the next step will likely involve serious study to prepare for the project, ensuring that the concepts are both appropriate and feasible. Knowledge of engineering, marine engineering, and ocean engineering would be used to develop the project. This project would take decades to complete, as it is not only an economic and environmental issue but also a matter of national security.

Regarding investment, Plodprasop said that the private sector would be responsible. Investors could receive long-term land concessions, potentially for 99 years, during which they could develop the islands for various purposes. These could include developing new tourist destinations as landmarks or building a smart city powered by clean energy, with features like wind turbines or solar panels. Once the concession period ends, the land would revert to the government.

The concept would have benefit including the government for flood protection infrastructure for economic and low-lying areas in Bangkok and its surrounding provinces, as well as the central region that could be affected by rising sea levels in the future.

Mr. Plodprasop Suraswadi, former Deputy Prime Minister and Chairman of the Environment Policy Committee, Pheu Thai Party

Conservation groups express concerns about effectiveness

However, following the announcement of the 'land reclamation' or 'Pearl Necklace of the Gulf of Thailand' project, several environmental groups have raised concerns regarding the suitability and effectiveness of the proposal.

The Beachlover group, a coastal conservation organization, has raised several points for consideration regarding the project from both an engineering and environmental perspective, as follows:

1. Sand Volume: Sand will be the primary material for land reclamation as the area to be reclaimed is a muddy seabed, and it is estimated that around 4 billion cubic meters of sand will be needed to fill approximately 282,000 rai (50 square kilometers x 9 islands), an area roughly equivalent in size to Samut Songkram Province.

2. Source of Sand: Typically, construction sand is sourced from riverbeds. However, over-extraction could lead to riverbank erosion and damage. Sand could also come from land or sea sources, but there are concerns about whether these will be sufficient. Therefore thorough study is needed for the potential sand sources in Thailand. Furthermore, if materials such as waste or debris, like those used for Kansai Airport in Japan, were considered, there are still doubts about the quantity and quality of such materials and whether they would be suitable for land reclamation.

3. Engineering Design: Proper design is necessary to support the weight and prevent future subsidence. Soil conditions and the potential for coastal erosion must be considered. The area near the shoreline consists of muddy silt, which has a high likelihood of subsiding, while there is a mix of sand farther out.

4. Construction Technology: While modern construction technologies and machinery are already used in Thailand such as for coastal protection and large port construction, previous reclamation projects have typically been close to shore and carried out on sandy seabeds. While the proposed project would involve filling an area approximately 1 kilometer offshore, where the seabed is predominantly mud, which has much higher sediment dispersion compared to sand. The group questions what technologies will be used to manage this project effectively, given the difference in conditions from past reclamation projects.

5. Water Circulation: Since the project involves creating islands offshore in the inner Gulf of Thailand, where waves from the south directly impact the area, these islands will block the main direction of the waves. This will inevitably alter the direction and speed of the currents, disrupting water circulation from behind the islands to the coastline. This can cause problems if the gates are opened or closed to manage water flow during critical times, as it would further disturb the circulation. This could lead to sediment accumulation behind the islands, extending to the coastline, which may negatively affect the coastal ecosystem, including mangrove forests. It could also disrupt fishing activities that rely on watercourse and potentially lead to water quality issues due to the reduced ability for wastewater to flow out to sea as it once did.

6. Ecological Impacts: The closure of two major river mouths, the Chao Phraya and Bang Pakong, especially mangrove forests, mudflats, and marine life that serve as human food sources is a significant concern. The area near the Bang Pakong River is home to dolphins, which can cause the risk to biodiversity. There is strong concern about the potential disruption of this ecosystem both during construction and in the long term once the project starts.

7. The project may not achieve its objectives: The project sets multiple objectives, primarily related to water management, such as preventing flooding in the inner city, protecting the city from the impact of rising sea levels, and preventing coastal erosion.

   • Flood Prevention: The use of sluice gates, which connect the islands, has been successful in several countries. However, when considering Thailand’s context—where even the management of sluice gates in rivers, reservoirs, and dams for irrigation and flood control has faced difficulties with efficiency due to various limitations, as frequently reported in the news—it becomes evident that the management of such large-scale sluice gates in a Mega project raises concerns about its effectiveness in truly achieving the project’s intended benefits.

   • Protecting the city from flooding due to rising sea levels: This objective could be achieved if implemented alongside other projects, such as raising the roads and creating an additional Green Belt within the city. Since the sluice gates connecting the islands will open and close to manage flooding, while sea level rise will not decline, it is likely that this project will not be able to fully protect or block the impacts of rising sea levels on the area behind the project.

   • Preventing coastal erosion: If the islands are built 1 kilometer away from the coastline, as reported, it is likely that the wind blowing over the surface of the sea will cause additional waves behind the islands, which will continue to hit the coast as before. Since the islands are not positioned far enough from the coast to prevent the development of waves, like the typical offshore seawall structures, the waves will still lose some height and energy compared to no islands. However, whether this reduction will decrease erosion depends on whether the primary cause of erosion.

Nevertheless, this project is still only a concept, with no detailed studies conducted.

The Netherlands: A Country of Land Reclamation

The Netherlands, a country known for its success in land reclamation, can be a model for Thailand’s concept of the "Gulf of Thailand Pearl Necklace" project.

The Netherlands is famous for its expertise in land reclamation, fighting sea waters for centuries. With 26% of its land below sea level, the country has faced the challenge of protecting its land from flooding. This unique situation has pushed the development of advanced water management technologies to create new land and protect the country from flooding.

Famous land reclamation projects in the Netherlands, such as the Zuiderzee Works and Delta Works are successful examples of creating new land from the sea for agriculture and urban development. The Zuiderzee Works is a massive project that transformed the shallow bay Zuiderzee into a freshwater lake by using land reclamation to create agricultural land and new urban areas. This project also helped prevent seawater from flooding low-lying areas.

Delta Works is a flood protection system consisting of dams and structures to control water currents, designed to protect against flooding from the sea during the rainy season. It is considered one of the world’s engineering wonders, this project plays an important role in protecting flooding in the Netherlands.

Although the Netherlands has been successful in land reclamation to manage flooding, the threat of rising sea levels due to climate change presents a new challenge. The existing dam systems may not be sufficient to handle future risks, prompting the Netherlands to continuously develop new water management technologies.

The Netherlands case study shows that land reclamation projects still face maintenance challenges as it requires ongoing care, such as managing water flow, preventing coastal erosion, and addressing other issues that may arise from the physical changes of the reclaimed areas.

The long-term sustainability of land reclamation is still in question due to the enormous budget required for ongoing maintenance. For instance, the land reclamation project in Dubai requires billions of dollars to keep the artificial islands in good condition and protect them from natural disasters.

Building cities on reclaimed land may seem like a good short-term solution, but in the long run, the risks from rising sea levels and extreme weather caused by climate change raise doubts about whether land reclamation is truly a sustainable solution. While many countries continue to use land reclamation to expand into urban areas to meet economic and housing needs, experts emphasize the importance of finding a balance between development and environmental conservation, taking into account the long-term impacts that land reclamation may have.

Delta Works, Netherlands