What's land reclamation?
Land reclamation is the process which creates new land from sea- or river-beds. It most commonly means converting wetlands or waterways into land for development.
The term can also mean the process of restoring damaged land to its natural state. The land reclaimed is known as reclamation ground or landfill.
Why land would be reclaimed
The main reason for land reclamation is simply to obtain more land in a specific location. The practice of filling in wetlands and waterways to obtain more useable land goes back a long time. Even in ancient times, humans tended to settle near lakes and rivers because water is essential for survival. Waterways also make transportation a lot easier. As human settlements continued to grow, however, the demand for land kept going up. So people started thinking about ways to expend their living space by converting more and more land into livable areas.
Reclaimed land is used for building houses, factories, roads, railways and many other forms of infrastructure. Reclaimed land can be very expensive, depending on its location. Seaside waterfronts in urban areas are especially prized by developers and well-off people alike.
Yet land reclamation is also used to repair environmental damage. For example, if a beach becomes severely eroded, beach nourishment may be used to restore it so as to preserve the existing environment. Heavily polluted land may also be put through a land reclamation scheme to remove pollutants and promote the re-establishment of native plant and animal species.
Land reclamation is also used to turn arid land into farmland in places that are experiencing desertification.
Forms of land reclamation
Landfills are waste disposal sites, but they can also be used to provide land for development. In many places with heavy urban development, more and more facilities are constructed on a completed landfill to make use of every square metre of available land. Some of the most common facilities built on landfills are parks and golf courses. In Hong Kong, where the demand for housing is extremely high, residential buildings are also constructed on landfills. For example, many residential buildings in the Tseung Kwan O area are built on completed landfills.
Artificial islands are also a form of land reclamation. They are created by expanding existing islets, constructing on reefs, or combining several natural islets into one bigger island. The Hong Kong International Airport is built on artificial islands. Two islands, Chek Lap Kok and Lam Chau, were joined together through land reclamation to form the piece of land where the airport now sits.
People have tended to eliminate wetlands around their settlements as part of the process of development. New York's Manhattan, one of the most prosperous areas on Earth, was once a swamp. The agricultural revolution in Europe saw a great decrease in wetlands as swamps, bogs, and fens were drained and turned into farmland. Natural wetlands play an important ecological role as they are home to many plants and animals. They are also a natural way to filter water. In an effort to protect the environment, man-made wetlands are constructed to restore natural habitats and ecosystems.
Land reclamation also occurs naturally. Mangrove swamps (below right) are coastal wetlands found in tropical and subtropical regions. They are home to salt-loving trees, shrubs and other plants that grow in brackish and saline tidal waters. These plants are often found in areas where fresh water meets salt water. The dense network of mangrove roots holds the soil together and allows coastal deposition to take place. That's nature way of land reclamation. Mangrove plants also filter waste matter from the land to the sea, and vice versa. Plant roots trap silt flowing out from rivers to the sea and help stabilise the coast.
In Hong Kong
Land reclamation in Hong Kong dates back to ancient times. In the early Western Han Dynasty (206 BC to 220 AD) beaches were reclaimed into fields for salt production.
The north shore of Hong Kong Island was one of the first places to undergo reclamation to create more land for urban development. Major land reclamation projects have been conducted since the mid-19th century. In 1859, reclamation along the coast of Sheung Wan was completed to create Queen's Road Central and Bonham Strand. From 1864 to 1866, reclamation was carried out along Causeway Bay waterfront and the Bowrington district in Wan Chai.
In 1989, the government completed a feasibility study and launched the Central and Wan Chai Reclamation project. There has since been increasing concern from the public that the balance might be lost between urban development and the beautiful natural scenery of Victoria harbour.
Hong Kong legislators passed the Protection of the Harbour Ordinance in 1996 to limit reclamation in Victoria harbour.
In 1995, a society for the protection of the harbour was founded by Winston Chu ka-sin to protect Victoria harbour from excessive reclamation and improper development. Since its establishment, the society has successfully torpedoed planned reclamation projects at Tamar Site, the North Point waterfront and the Wan Chai waterfront.
Impact on the environment
Land reclamation can be damaging to corals and marine life. Marine animals, such as fish, might not have enough food after underwater ecosystems are destroyed in the process of land reclamation. Soil used to reclaim land may also spoil water, making it unsuitable for corals and myriad forms of marine life.