Land reclamation, often known as reclamation, and also known as land fill (not to be confused with a waste landfill), is the process of creating new land from oceans, seas, riverbeds or lake beds. The land reclaimed is known as reclamation ground, reclaimed land, or land fill.
In some jurisdictions, including parts of the United States,[1] the term "reclamation" can refer to returning disturbed lands to an improved state. In Alberta, Canada, for example, reclamation is defined by the provincial government as "The process of reconverting disturbed land to its former or other productive uses."[2] In Oceania, it is frequently referred to as land rehabilitation.
In Ancient Egypt, the rulers of the Twelfth Dynasty (c. 2000–1800 BC) undertook a far-sighted land reclamation scheme to increase agricultural output. They constructed levees and canals to connect the Faiyum with the Bahr Yussef waterway, diverting water that would have flowed into Lake Moeris and causing gradual evaporation around the lake's edges, creating new farmland from the reclaimed land. A similar land reclamation system using dams and drainage canals was used in the Greek Copaic Basin during the Middle Helladic Period (c. 1900–1600 BC).[3] One of the earliest large-scale projects was the Beemster Polder in the Netherlands, realized in 1612 adding of land. In Hong Kong the Praya Reclamation Scheme added NaNacres of land in 1890 during the second phase of construction. It was one of the most ambitious projects ever taken during the Colonial Hong Kong era.[4] Some 20% of land in the Tokyo Bay area has been reclaimed,[5] most notably Odaiba artificial island. The city of Rio de Janeiro was largely built on reclaimed land, as was Wellington, New Zealand.
Land reclamation can be achieved by a number of different methods. The simplest method involves filling the area with large amounts of heavy rock and/or cement, then filling with clay and dirt until the desired height is reached. The process is called "infilling"[6] and the material used to fill the space is generally called "infill".[7] [8] Draining of submerged wetlands is often used to reclaim land for agricultural use. Deep cement mixing is used typically in situations in which the material displaced by either dredging or draining may be contaminated and hence needs to be contained. Land dredging is also another method of land reclamation. It is the removal of sediments and debris from the bottom of a body of water. It is commonly used for maintaining reclaimed land masses as sedimentation, a natural process, fills channels and harbors.[9]
Agriculture was a driver of land reclamation before industrialisation.[28] In South China, farmers reclaimed paddy fields by enclosing an area with a stone wall on the sea shore near a river mouth or river delta. The species of rice that are grown on these grounds are more salt tolerant. Another use of such enclosed land is the creation of fish ponds. It is commonly seen on the Pearl River Delta and Hong Kong. These reclaimed areas also attract species of migrating birds.
A related practice is the draining of swampy or seasonally submerged wetlands to convert them to farmland. While this does not create new land exactly, it allows commercially productive use of land that would otherwise be restricted to wildlife habitat. It is also an important method of mosquito control.
Even in the post-industrial age, there have been land reclamation projects intended for increasing available agricultural land. For example, the village of Ogata in Akita, Japan, was established on land reclaimed from Lake Hachirōgata (Japan's second largest lake at the time) starting in 1957. By 1977, the amount of land reclaimed totalled .[29]
Artificial islands are an example of land reclamation. Creating an artificial island is an expensive and risky undertaking. It is often considered in places with high population density and a scarcity of flat land. Kansai International Airport (in Osaka) and Hong Kong International Airport are examples where this process was deemed necessary. The Palm Islands, The World and hotel Burj al-Arab off Dubai in the United Arab Emirates are other examples of artificial islands (although there is yet no real "scarcity of land" in Dubai), as well as the Flevopolder in the Netherlands which is the largest artificial island in the world.
See main article: Beach nourishment. Beach rebuilding is the process of repairing beaches using materials such as sand or mud from inland. This can be used to build up beaches suffering from beach starvation or erosion from longshore drift. It stops the movement of the original beach material through longshore drift and retains a natural look to the beach. Although it is not a long-lasting solution, it is cheap compared to other types of coastal defences. An example of this is the city of Mumbai.[12]
As human overcrowding of developed areas intensified during the 20th century, it has become important to develop land re-use strategies for completed landfills. Some of the most common usages are for parks, golf courses and other sports fields. Increasingly, however, office buildings and industrial uses are made on a completed landfill. In these latter uses, methane capture is customarily carried out to minimize explosive hazard within the building.
An example of a Class A office building constructed over a landfill is the Dakin Building at Sierra Point, Brisbane, California. The underlying fill was deposited from 1965 to 1985, mostly consisting of construction debris from San Francisco and some municipal wastes. Aerial photographs prior to 1965 show this area to be tidelands of the San Francisco Bay. A clay cap was constructed over the debris prior to building approval.[30]
A notable example is Sydney Olympic Park, the primary venue for the 2000 Summer Olympic Games, which was built atop an industrial wasteland that included landfills.
Another strategy for landfill is the incineration of landfill trash at high temperature via the plasma-arc gasification process, which is currently used at two facilities in Japan, and was proposed to be used at a facility in St. Lucie County, Florida.[31] The planned facility in Florida was later canceled.[32]
Draining wetlands for ploughing, for example, is a form of habitat destruction. In some parts of the world, new reclamation projects are restricted or no longer allowed, due to environmental protection laws. Reclamation projects have strong negative impacts on coastal populations, although some species can take advantage of the newly created area.[33] A 2022 global analysis estimated that 39% of losses (approximately 5300disp=orNaNdisp=or) and 14% of gains (approximately 1300disp=orNaNdisp=or) of tidal wetlands (mangroves, tidal flats, and tidal marshes) between 1999-2019 were due to direct human activities, including conversion to aquaculture, agriculture, plantations, coastal developments and other physical structures.[34]
The State of California created a state commission, the San Francisco Bay Conservation and Development Commission, in 1965 to protect San Francisco Bay and regulate development near its shores. The commission was created in response to growing concern over the shrinking size of the bay.
Hong Kong legislators passed the Protection of the Harbour Ordinance, proposed by the Society for Protection of the Harbour, in 1997 in an effort to safeguard the increasingly threatened Victoria Harbour against encroaching land development.[35] Several large reclamation schemes at Green Island, West Kowloon, and Kowloon Bay were subsequently shelved, and others reduced in size.
Reclaimed land is highly susceptible to soil liquefaction during earthquakes,[36] which can amplify the amount of damage that occurs to buildings and infrastructure. Subsidence is another issue, both from soil compaction on filled land, and also when wetlands are enclosed by levees and drained to create polders. Drained marshes will eventually sink below the surrounding water level, increasing the danger from flooding.
| Country or territory | Notes | |
|---|---|---|
 Bahrain | 76.3% of original size of 410km2 (1931–2007). [37] | |
 Bangladesh | About 110km2 in total and has potential (8% of total area) up to depth in the territorial sea area.[38] | |
 Hong Kong | See main article: article and Land reclamation in Hong Kong. 67km2 of land was reclaimed up to 2013. Praya Reclamation Scheme began in the late 1860s and consisted of two stages totaling 50to. Hong Kong Disneyland, Hong Kong International Airport, and its predecessor, Kai Tak Airport, were all built on reclaimed land. In addition, much reclamation has taken place in prime locations on the waterfront on both sides of Victoria Harbour. This has raised environmental issues of the protection of the harbour which was once the source of prosperity of Hong Kong, traffic congestion in the Central District,[39] as well as the collusion of the Hong Kong Government with the real estate developers in the territory.[40] [41] In addition, as the city expanded, new towns in different decades were mostly built on reclaimed land, such as Kwun Tong, Sha Tin-Ma On Shan, Tai Po, Tseung Kwan O, Tuen Mun, and West Kowloon. | |
 India | Mumbai – An archipelago of originally seven separate islands were joined by land reclamation over a span of five centuries. This was done to develop Mumbai as a harbour city. | |
 Indonesia | Jakarta – Giant Sea Wall Jakarta is part of a massive coastal development project at Jakarta Bay. | |
 Japan | ||
 Macao | 170% of the original size or 17km2[43] | |
| In the 1980s, North Korea commenced a "find new land" program to reclaim 300,000 hectares of land (3,000 km2 or 1,160 mi2) in order to expand the country's supply of arable land. The project was unsuccessful and only reclaimed 20,000 hectares (200 km2 or 70 mi2) by the time it was cancelled after the death of Kim Il-sung in 1994. It also contributed to the collapse of the North Korean economy and the subsequent famine in the 1990s. Land reclamation efforts resumed in the 2010s under Kim Jong-un with more success. North Korea constructed artificial islands in the Yellow Sea containing Korean People's Army bases, possibly inspired by Chinese artificial islands in the South China Sea and possibly as bases for long-range ballistic missiles.[44] [45] [46] | ||
 Philippines |
See main article: article and Land reclamation in Metro Manila. Additional 626 hectares along the eastern coast of Manila Bay created in the 1990s[47] to the 88-hectare Cultural Center of the Philippines Complex. The shore road of Manila (Roxas Boulevard) is actually reclaimed land, as well as its extension road to Cavite (Manila-Cavite Expressway / Aguinaldo Boulevard).
| |
 Singapore | See main article: article and Land reclamation in Singapore. 20 percent of the original size or 135km2., plans for 99km2 more are to go ahead,[48] even though disputes persist with Malaysia over Singapore's extensive land reclamation works.[49] Parts of Changi Airport are also on reclaimed land. | |
| As of 2006, 38 percent or 1550km2 of coastal wetlands reclaimed, including 400km2 at Saemangeum. Songdo International Business district, the largest private development in history, is a large-scale reclamation project built entirely on tidal mudflats. | ||
 United Arab Emirates | See main article: Land reclamation in the United Arab Emirates. Dubai has a total of four reclaimed islands (the Palm Jumeirah, Jebal Ali, The Burj al Arab Island, and The World Islands), with a fifth under construction (the Palm Deira). There are several human-made islands in Abu Dhabi, such as Yas Island and Al Lulu Island. |
| Country | Notes | |
|---|---|---|
 Monaco | See main article: Land reclamation in Monaco. 0.41km2 out of 2.05km2, or one fifth of Monaco comes from land taken from the sea, mainly in the neighborhoods of Fontvieille, La Condamine, and Larvotto/Bas Moulins. | |
 Netherlands | See main article: article and Land reclamation in the Netherlands. About 1/6 (almost 17%) of the entire country, or about 7000km2 in total, has been reclaimed from the sea, lakes, marshes and swamps. The province of Flevoland has almost completely been reclaimed from the Zuiderzee. |
| Country | Notes | |
|---|---|---|
| Significant areas of land totalling several hundred hectares have been reclaimed along the harbourfronts of Auckland, Dunedin, and Wellington. In Dunedin – which in its early days was nicknamed "Mudedin" – around 2.5km2, including much of the inner city and suburbs of Dunedin North, South Dunedin, and Andersons Bay is reclaimed from the Otago Harbour, and a similar area in the suburbs of St Clair and St Kilda is reclaimed swampland. The international airports serving Auckland and Wellington have had significant reclamation for runway use.[50] [51] | ||
| Eko Atlantic,[52] Lagos – 25 square kilometers |
| 13,500+ km2 | Land reclamation in China | ||
| 7,000 km2 | Flevoland, de Beemster, Afsluitdijk Land reclamation in the Netherlands | ||
| 1,550 km2 | |||
| 1,000+ km2 | Artificial islands of the United States | ||
| 500+ km2 | |||
| 470 km2 | Land reclamation in the United Arab Emirates | ||
| 410 km2 | |||
| 135 km2 | Land reclamation in Singapore | ||
| 110 km2 | |||
| 67 km2 | Land reclamation in Hong Kong | ||
| 35 km2 | |||
| 17 km2 | |||
| 9.26 km2 | Cebu South Road Properties Central Business District and Land reclamation in Metro Manila | ||
| 3.3 km2 | Reclamation of Wellington Harbour[53] | ||
| 2.33 km2 | Colombo International Financial City[54] | ||
| 1.94 km2 | Cape Town Foreshore[55] | ||
| 0.62 km2 | Velana International Airport[56] | ||
| 0.41 km2 | Land reclamation in Monaco |