Explained: What Is Land Reclamation

Coastal regions, particularly in East Asia, the Middle East, and West Africa, are gaining economic importance resulting in a surge in land reclamation endeavours worldwide.

Although these projects bring about economic benefits, they also face significant environmental challenges and potential risks due to the escalating sea levels and the occurrence of storm surges.

A recent study analysed satellite imagery of coastal cities with populations of at least 1 million and discovered that land reclamation projects have created approximately 2,530 square kilometres (more than 900 square miles) of coastal land.

Unsplash/Representational image

The majority of this new land, nearly 90%, was developed in East Asia over the past 20 years, primarily to accommodate industrial and port facilities serving the global economy.

China accounted for about 350 square kilometres of the newly reclaimed land between 2000 and 2020, while Singapore and Incheon (South Korea) also undertook significant reclamation efforts.

What is Land reclamation?

Land reclamation involves modifying the natural features of bodies of water like seas, rivers, lakes, or marshes to create new land. It can occur along coastlines or inland by converting wetlands or other water bodies.

Unsplash/Representational image

It aims to expand coastal areas for various purposes, such as agriculture and industry. It has been practised for many years to create new usable land from existing bodies of water.

Old vs. modern land reclamation

Traditional land reclamation involved constructing dikes to enclose tidal marshes or shallow waters and then draining these areas to create dry land. This process often involved diverting streams to bring in sediment, which helped build up the land to a higher level. Additionally, soil and stone could be excavated from the mainland and deposited along the shore or existing islands, gradually expanding the land into the sea.

While modern land reclamation methods involve large-scale engineering projects that employ offshore concrete barrier walls. These walls are filled with significant amounts of sand, earth, clay, or rock, often transported from distant locations. Another approach is hydraulic reclamation, where the reclamation site is filled with dredged soil from the seafloor mixed with water.

What are the issues?

The issues associated with land reclamation include coastal flooding risks and the destruction of seabed ecosystems due to the extraction of materials like sand. These concerns highlight the environmental consequences and potential harm to both human and marine life.

Unsplash/Representational image

One major concern is coastal flooding, as a significant portion of reclaimed land is at high risk of flooding due to storm surges and the combined effects of global warming and land subsidence. This poses a threat to the newly reclaimed areas and the communities residing there.

Another issue is the distortion of seabed ecosystems. Land reclamation often involves obtaining materials like sand from marine and river environments. This extraction can lead to the destruction of habitats and spawning grounds for various organisms.

In response to this ecological impact, some countries have banned the export of sand for land reclamation. As a result, construction companies have resorted to extracting sand and clay from the ocean floor, further damaging the seabed ecosystem.