Creating new land from oceans, seas, riverbeds or lakes
This article is about land reclaimed from ocean, riverbeds, or lake beds. For land reclaimed from the desert, see
Dedesertification. For the disposal of waste material, see
landfill.
"Reclaimed" redirects here. For other uses, see
Reclaim.
Land reclamation, usually 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 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.
History
One of the earliest large-scale projects was the
Beemster Polder in the Netherlands, realized in 1612 adding 70 square kilometres (27 sq mi) of land. In Hong Kong the
Praya Reclamation Scheme added 20 to 24 hectares (50 to 60 acres) 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.[3] Some 20% of land in the
Tokyo Bay area has been reclaimed,[4] most notably
Odaiba artificial island. Le Portier, Monaco and
Gibraltar are also expanding due to land reclamation. The city of
Rio de Janeiro was largely built on reclaimed land, as was
Wellington,
New Zealand.
Methods
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"[5] and the material used to fill the space is generally called "infill".[6][7] 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.[8]
The shore of
Jakarta Bay. Land is usually reclaimed to create new housing areas and real estate properties, for the rapidly expanding city of
Jakarta. So far, the largest reclamation project in the city is the creation of Golf Island, north of
Pantai Indah Kapuk.[13]
Considerable areas of
Dunedin, New Zealand, including the "
Southern Endowment", stretching from the central city to the southeastern suburbs along the shore of
Otago Harbour.
Prior to the
Napier earthquake of 1931, significant reclamation of the
then-lagoon was undertaken in areas of Napier South and Ahuriri. There were also minor reclamation works undertaken after 1931 on the new low-lying lands brought up by the earthquake.
Areas around
Wellington and
Auckland's harbours have also been reclaimed.
South America
Parts of
Panama City urban and street development are based on reclaimed land, using material extracted from
Panama Canal excavations.
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
wildlifehabitat. 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 172.03 square kilometres (66.42 sq mi).[23]
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.[10]
Landfill
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.
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 will be used at a planned facility in
St. Lucie County,
Florida.[25]
Environmental impact
Parts (highlighted in brown) of the
San Francisco Bay were reclaimed from wetlands for urban use.
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.[26] A 2022 global analysis estimated that 39% of losses (approximately 5,300 km2 or 2,000 sq mi) and 14% of gains (approximately 1,300 km2 or 500 sq mi) 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. [27]
Environmental legislation
A map of reclaimed land (grey area) in Hong Kong. Many of the urban areas of Hong Kong are on reclaimed land.
Reclaimed land is highly susceptible to
soil liquefaction during earthquakes,[29] 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.
About 110 km2 (42 sq mi) in total and has 12,000 square kilometres (4,600 sq mi) potential (8% of total area) up to 12 metres (39 ft) depth in the territorial sea area.[31]
170% of the original size or 17 km2 (6.6 sq mi)[35]
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.
Cebu South Road Properties,
Cebu City, Philippines - Artificial island which is 300 hectares was built along the sea between Mainland Cebu and Kawit Island. This was done to address the increasing need of urban and residential development in
Cebu City due to its very progressive economy.
20 percent of the original size or 135 km2 (52 sq mi). As of 2003[update], plans for 99 km2 (38 sq mi) more are to go ahead,[38] even though disputes persist with Malaysia over Singapore's extensive land reclamation works.[39] Parts of
Changi Airport are also on reclaimed land.
South Korea
As of 2006, 38 percent or 1,550 km2 (600 sq mi) of coastal wetlands reclaimed, including 400 km2 (150 sq mi) at
Saemangeum.
Songdo International Business district, the largest private development in history, is a large-scale reclamation project built entirely on tidal mudflats.
North Korea
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.[40][41][42]
about 1/6 (almost 17%) of the entire country, or about 7,000 km2 (2,700 sq mi) in total, has been reclaimed from the sea, lakes, marshes and swamps. The province of
Flevoland has almost completely been reclaimed from the
Zuiderzee.
– 0.41 km2 (0.16 sq mi) out of 2.05 km2 (0.79 sq mi), or one fifth of Monaco comes from land taken from the sea, mainly in the neighborhoods of Fontvieille,
La Condamine, and
Larvotto/Bas Moulins.
New Zealand – significant areas of land totalling several hundred hectares have been reclaimed along the harbourfronts of
Auckland,
Wellington and
Dunedin. In Dunedin – which in its early days was nicknamed "Mudedin" – around 2.5 km2 (0.97 sq mi), 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.[44][45]
^Murray N. J., Clemens R. S., Phinn S. R., Possingham H. P. & Fuller R. A. (2014) Tracking the rapid loss of tidal wetlands in the Yellow Sea. Frontiers in Ecology and the Environment 12, 267–72.
doi:
10.1890/130260
^Brian Lander. State Management of River Dikes in Early China: New Sources on the Environmental History of the Central Yangzi Region . T'oung Pao 100.4-5 (2014): 325–362; Mira Mihelich, “Polders and Politics of Land Reclamation in Southeast China during the Northern Sung” (Ph.D. dissertation, Cornell Univ., 1979); Peter Perdue, Exhausting the Earth: State and Peasant in Hunan 1500–1850 (Cambridge, Massachusetts: Harvard University Council on East Asian Studies, 1987); Mei Li 梅莉, Zhang Guoxiong 張國雄, and Yan Changgui 晏昌貴, Lianghu pingyuan kaifa tanyuan 兩湖平原開發探源 (Nanchang: Jiangxi jiaoyu chubanshe, 1995); Shiba Yoshinobu, “Environment versus Water Control: The Case of the Southern Hangzhou Bay Area from the Mid-Tang Through the Qing,” in Sediments of Time: Environment and Society in Chinese History, ed. Mark Elvin and
Ts'ui-jung Liu (Cambridge: Cambridge University Press, 1998), 135–64
^Paul B. Awosika and Marc Papineau, Phase One
Environmental Site Assessment, 7000 Marina Boulevard, Brisbane, California, prepared for
Argentum International by Certified. Engineering & Testing Company, Boston, Massachusetts, July 15, 1993
^"Singapore". The World Factbook.
CIA. 1 September 2010. section Transnational issues. Retrieved 1 October 2010. disputes persist with Malaysia over […] extensive land reclamation works
^Omotosho, Jimmy (2013). "New Cities and Real Estate Markets- A focus on the Eko Atlantic City Project". Proceedings of the 13th African Real Estate Society Conference. African Real Estate Society.
doi:
10.15396/afres2013_109.