Box Story: Semakau Landfill Project – The “Garbage of Eden”

Background

In 1992, Singapore faced a waste management challenge. Existing landfills (for example, at Lim Chu Kang and Lorong Halus) were nearing maximum capacity, while approved sites for future landfill projects had to be re-zoned for other uses. An urgent solution was required to address waste management needs while safeguarding land areas for future development in land-scarce Singapore.

The government leveraged Singapore’s expertise in land reclamation and conducted rigorous feasibility studies on the viability of an offshore landfill. This led to the genesis of the Semakau Landfill project—the first man-made offshore landfill in the region, created entirely out of sea-space.

However, members of the public and environmental advocacy groups were not in favour with the idea of an offshore landfill. As the conversion of Semakau Island into a landfill impacted natural space and marine habitats, opponents of the project were concerned that the ecological balance and biodiversity of the area may be disrupted, leading to long-term negative impacts on the surrounding coral reefs, marine life and water quality.

Questions were also raised about Singapore’s ability to comply with stringent international environmental regulations and standards, as well as the long-term sustainability of a landfill on an offshore island.

Collaborative Efforts

A multi-agency approach was undertaken to address various aspects of the project, with each agency taking the lead according to its expertise. The National Environment Agency (NEA) provided regulatory oversight of the project, ensuring that it complied with environmental regulations and standards for waste management systems; the JTC led the development of industrial infrastructure for the facility; and the PUB provided input on the water quality and environmental impact considerations.

Semakau Landfill in 2022 (National Environment Agency)

The agencies jointly conducted environmental impact assessments to evaluate the potential implications of the landfill project, and brainstormed for systemic solutions to minimise the impact of the project on marine ecosystems, water quality and surrounding environments. These assessments led to the eventual solution of developing Semakau Landfill by joining two smaller islands—Pulau Semakau and Pulau Sakeng—with a 7-km perimeter bund, enclosing part of the sea in between. The bund was linked with an impermeable membrane, marine clay and rock layers to keep leachate within the area and the surrounding waters free of pollution.

Apart from the joint planning and development of Semakau Landfill, the NEA and PUB worked together to conduct public engagement and education initiatives to raise awareness about waste management, environmental stewardship, and the role of the landfill in Singapore’s overall waste management strategy and sustainability goals. The landfill began operations in April 1999, enabling the last mainland landfill at Lorong Halus to close after it was filled.

Achieving Integrated Outcomes Through Close Inter-Agency Collaboration

The inter-agency approach undertaken to address the concerns at a systemic level led to the eventual development of the Semakau Landfill as an integrated solution in waste management and environmental conservation. Recent monitoring efforts have shown no indication of deterioration in Semakau Island’s surrounding seawater quality, and natural ecosystems are reportedly flourishing in the waters. Since 2005, Semakau has been open to the public for recreational activities such as guided nature walks, sport fishing tours and stargazing. It is also a testbed for new innovations, such as a floating wastewater treatment plant, and in the future, renewable energy solutions such as a micro-grid that integrates multiple energy sources. Dubbed the “Garbage of Eden”, the Semakau Landfill project has evolved beyond being a solution for Singapore’s waste management challenges. It exemplifies the synergistic impact when agencies with different strengths collaborate towards “win-win” outcomes that benefit the greater whole.

Semakau today offers habitat for biodiversity in its mangrove forests (top images), seagrass meadows (bottom left) and intertidal zone (bottom right) (National Environment Agency)