Swallowing the sea

Singapore’s land mass has increased 25 per cent since the 1800s. Video: Google Earth.

“With land reclamation, they’re basically dumping loads of sand onto areas where there’s probably a whole ecosystem with diverse species. When you take away the habitat from all these species, I suppose most of them would end up either dead or … if there is time, the bigger ones would probably be displaced.”

Marine biologist Tiffany Goh is talking about the process of land reclamation and how it will adversely affect marine biodiversity at Changi Bay.

Geographically located in the east region of Singapore, Changi Bay is home to an array of marine life. According to the Housing and Development Board of Singapore (HDB), land reclamation at Changi Bay will commence at the end of this year. Around 900 hectares of land will be reclaimed, but the specific use of the land is still being determined.

Property experts predict the land will be used for military, infrastructure, or industrial purposes due to its proximity to the airport and military operations.

Less apparent than Singapore’s vertical shift, the country’s horizontal growth in land mass isn’t because of tectonic changes – but man-made engineering – known as land reclamation. The last two centuries has seen Singapore’s land mass expand from 540 km2 in the 1800s to the current 728 km2, to accommodate the rapid expansion of commerce, industry, transport infrastructure, and housing.

Nanyang Technological University assistant professor Xungchang Fei says land reclamation is the process of creating new land from the sea, wetlands, or other water bodies by filling the area with large amounts of heavy rock or cement, then filling the area with clay and soil until the height desired is reached.

How does land reclamation impact marine biodiversity?

The development of new land was a key component to the country’s rise from third world to first world, but the success of remaking its coastline created ecological and social costs. Most of the original shore, mangrove forests, natural beaches, and coral reefs were lost.

Tiffany Goh says the process of land reclamation could have long-term impacts on marine life and its ecosystem.

According to the Environmental Impact Assessment (EIA), the direct impacts can mean the complete loss of the ocean floor habitat, turtle nesting sites, dugong feeding site, loss of seagrass, intertidal zones, corals, and mangrove habitats located within the development site at Changi Bay. For indirect impacts, EIA reports sedimentation in the water will affect the surrounding seagrass and coral habitats, underwater noises and artificial lights will disturb other animals like whales, otters, dolphins, turtles, and fishes, risks of water discharge, and complete clearance of terrestrial area that affects flora and fauna.

Environmental consultant Willem John says to mitigate negative impacts, environmental monitoring is essential while reclamation work is being conducted.

“During the reclamation process, monitoring the water currents is important because there’s quite a bit of machinery moving around in the water …  if it impacts the direction of the currency, it could impact marine biodiversity. If the water direction changes, this could have a knock-on effect on plankton and other species, which then in turn, could impact the larger mammals like the dugongs … it could impact their breeding cycles,” he says.

Lee Kiang Ng is the founder of Young Nautilus, a science and nature education group. She says a significant amount of biodiversity will be lost during land reclamation.

“It’s inevitable that we will lose the biodiversity at that location, I think that nature has been proven to be quite strong. So, for a short period of time we will lose the ecosystem wildlife, but over the years, who knows it might be able to bounce back.”

Lee Kiang Ng

Changi Bay is one of the only nesting grounds suitable for turtles in Singapore, and according to the EIA, the loss of habitat will negatively impact the reptiles if the reclamation goes ahead.

Ng says the female turtles will try to instinctively travel to the beach they hatched from to lay their own eggs.

“What we know is that they [turtles] will usually try to go back to the same place, but it depends, they will probably be able to find other locations nearby to lay the eggs,” she says.

Green turtle’s call Singapore’s waters home. Video: Supplied.

Ng says intertidal seagrass and mangrove habitat play an important ecological function in our marine ecosystem.

“Seagrass has a lot of important functions; it is a habitat within itself. A lot of organisms that we probably don’t see … live among the seagrasses. It is a very important home for these animals, and for other animals, it is an important source of food. In Singapore, we have dugongs … but most of the time we don’t really see them. We have a very nice seagrass meadow at car park seven in Changi Bay and we do see the dugong feeding trail every now and then,” she says.

The flora problem

The Singapore Reef Survey and Conservation Project was launched in 1988 to preserve coral health in Singaporean waters and save what remained.

Between 1991 and 1997 the Nature Society Marine Conservation Group commenced the Reef Rescue Project and divers relocated coral from reclamation sites, but later surveys found only 10 per cent of relocated corals survived. Located between Changi Beach Park and Tanah Merah Ferry Terminal, the EIA reports the reclamation site spans across more than 7 hectares of secondary coastal vegetation, corals, mangroves, and seagrass. Most reef-building corals have photosynthetic cells, called zooxanthellae, found within their tissues. Zooxanthellae produces oxygen and aids the coral to remove waste, and supplies the coral with glycerol, glucose, and amino acids – the formula for photosynthesis.

Tiffany Goh says water column is another factor affecting the growth of flora.

“You also have the long-term effects of having resuspended particles in the water column, and this would affect corals, seagrass, or any kind of marine life that requires sun for photosynthesis. With all these particles in the water column, the amount of light received is reduced … this would impact the growth of corals, algae, and seagrass,” she says.

Urban planner Cameron Liebgott says the rapid growing population and lack of land availability is a reason why countries reclaim land.

“I would say that land reclamation isn’t sustainable as I feel as it is similar to cutting down trees to make way for development. Removing water for new development doesn’t add up … with rapid water levels it will be under water in coming years. The government and planning bodies are trying to accommodate for the increase in population to add more development. We got told that it is around 15 to 20 years until that land can be used after it’s been filled, which is heavy planning for the future when it can all change rapidly,” he says.

Head of Marine and Coastal Solutions KL Dr Juan Savioli says land reclamation is neither good nor bad, it all depends on how it is implemented.

“In many cases, when properly carried out, it can produce very positive results. Conversely, when badly managed the results can be very negative. There is no right or wrong, the question lies on if it is necessary and how we implement it,” he says.

Alternatives to land reclamation

Polder development reduces sand usage for land reclamation. Video: Housing & Development Board.

With a global sand shortage, Singapore is the world’s largest importer – importing 13 per cent of the world’s sand.  The iconic Changi Airport commenced construction in 1975 and was built with more than 40 million cubic metres of sand reclaimed from the seabed. Other countries conducting coastal land reclamation include the Netherlands, Hong Kong, and China.

Like the other countries, Singapore is adopting the Dutch polder method of land reclamation. Unlike the conventional method, the polder method creates a tract of reclaimed land from the sea by constructing a dyke and network of drains, water pumping systems, and canals.

This method could reduce the amount of sand needed for land reclamation, and advocates say it is more cost efficient. Deltares experts conducted an environmental study and found the environmental impact on surrounding marine receptors would be minimal.

Video: Andrew Du

The 2022 Curtin Journalism Singapore Study Tour was funded under the federal government’s New Colombo Plan scheme.