Shoring Up Sustainability - Reshaping the Coastline of Pulau Tekong

Find out how Goh Pei Ling, Acting Deputy Director (Land Reclamation Section 1) in Infrastructure and Reclamation Department at the Housing and Development Board, is literally changing the shape of Singapore and making sustainability more than just a buzzword.

As a land-scarce country, Singapore has been reclaiming land since the 19th century, typically through infill, the traditional method of land reclamation. Infill relies heavily on sand procurement, which leaves Singapore susceptible to price fluctuations of sand imports. In a bid to substantially reduce our dependence on sand, the government continues to explore alternative land reclamation practices like polders. Pei Ling spearheads the polder initiative at Pulau Tekong.

“Polder development is a breakthrough in how Singapore could reclaim land in the future,” Pei Ling says. “Not only will creating new land through empoldering provide a sustainable alternative for Singapore to meet long-term land needs, but it also offers the flexibility to adapt to the evolving coastal environment and sea level.”

Aerial view of the pilot polder project taking place at Pulau Tekong. This first-of-its-kind land reclamation project is meant to reduce Singapore’s dependency on sand imports. (Photo credit: HDB)

Essentially, a polder is a reclaimed tract of land that is below surrounding sea level. It is typically protected by a dike. “The polder is then managed by a system of drainage canals and pumps which control the water levels within it,” Pei Ling explains. Rainwater is channelled by drains to a stormwater collection pond, while a central pumping station circulates the water to ensure good water quality. Meanwhile, a drainage pumping system pumps excess water out to the sea. This network of drains and water pumping systems prevent the polder from becoming waterlogged.

Creating Spaces for Growth

Singapore’s population is expected to increase to 6.9 million by 2030, so the need to create more homes, working and recreational environments inevitably puts pressure on finding more space. With the completion of this pilot project, the 8,100,000 square metres of Polder will add approximately the size of two Toa Payoh towns to Singapore’s overall land mass at Pulau Tekong. With more land freed up for military exercises, the government can begin shifting old bases to make space for residential and commercial developments.

Having been with HDB for 13 years now, Pei Ling is no stranger to sustainability projects. She was involved in the creation of My WaterWay@Punggol, Singapore’s longest man-made waterway. An environmentally sustainable project to intensify the surrounding greenery, it has brought waterfront recreational facilities and transformed Punggol into a vibrant waterfront town, boosting biodiversity in the area by about 20% since its launch.

Land reclamation methods, even ones designed to leave as small a biological footprint as polders, could bring about negative environmental impact in the form of biodiversity loss. “Understanding the possible implications, we work closely with non-governmental organisations and the National Parks Board (NParks) to study how best we could avoid or minimise the impact,” says Pei Ling.

One example is Pulau Unum, a small isle on the northern coast of Pulau Tekong. “We have avoided reclaiming over Pulau Unum to preserve its biodiversity,” she says. “Instead, a water channel is created between the polder and Pulau Unum to allow water exchange around the island for mangrove growth.” The team has also worked with NParks to identify important species of mangroves and terrestrial plants to conserve or replant.

Sustainability in the Present and Beyond

The success of this pilot project at Pulau Tekong could spell endless possibilities for Singapore’s coastal management in the future. “Polders allow for flexibility to adapt to the rising sea level,” Pei Ling explains. “For normal reclaimed land, it will be difficult to raise the land level once there is intense development on the land. However, for a polder, the dike crest can be elevated progressively whenever necessary if sea level is projected to rise further.”

From the drawing board to actualisation, land reclamation is challenging, back-breaking work. Despite the difficulties, seeing how the project takes shape and comes to life gives Pei Ling a strong sense of fulfilment. This ability to transform ideas into reality is what drew her to engineering in the first place.

“To be able to apply engineering knowledge to solve real-world problems and to know that your solutions are making a difference to people — to me, this is the best part of engineering.”

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