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Land reclamation

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This is an old revision of this page, as edited by 71.82.209.86 (talk) at 10:21, 14 March 2014 (→‎Methods of Reclamation: Dredging is NOT reclamation, it's for making waterways deeper, nothing to do with filling waterways to create land.). The present address (URL) is a permanent link to this revision, which may differ significantly from the current revision.

For the sense of restoration, see land restoration.
"Reclaimed" redirects here. For other uses, see Reclaim.
Reclaiming in Perth, Australia 1964

Land reclamation, usually known as reclamation, and also known as land fill (not to be confused with a landfill), is the process of creating new land from ocean, riverbeds, or lake. The land reclaimed is known as reclamation ground or land fill.

In a number of other 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.

Methods of Reclamation

Land reclamation can be achieved with a number of different methods. The most simple method involves simply filling the area with large amounts of heavy rock and/or cement, then filling with clay and dirt until the desired height is reached. Draining of submerged wetlands is often used to reclaim land for agricultural use. Deep cement mixing is used typically in situation in which the material displaced by either dredging or draining may be contaminated and hence needs to be contained.

Habitation

The entire East Coast Park in Singapore was built on reclaimed land with a man-made beach.
The Flevopolder in the Netherlands, reclaimed from the IJsselmeer, is the largest artificial island in the world.
Land Reclamation in the Beirut Central District
The whole district of Fontvieille, Monaco was reclaimed from the sea

The creation of new land was for the need of human activities.

Notable examples include:

One of the earliest large scale projects was the Beemster Polder in the Netherlands, realized in 1612 adding 70km2 of land. In Hong Kong the Praya Reclamation Scheme added 50 to 60 acres (20.2 to 24.3 ha) 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.

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.

Agriculture

Land reclamation in progress in Bingzhou (丙州) Peninsula (formerly, island) of the Dongzui Bay (东咀港). Tong'an District, Xiamen, China

Agriculture was a drive for land reclamation before industrialisation.[5] In South China, farmers reclaimed paddy fields by enclosing an area with a stone wall on the sea shore near river mouth or river delta. The species of rice that grow on these grounds are more salt tolerant. Another use of such enclosed land is creation of fish ponds. It is commonly seen on the Pearl River Delta and Hong Kong. These reclamation also attracts 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 Hachirogata (Japan's second largest lake at the time) starting in 1957. By 1977, the amount of land reclaimed totalled 172.03 square km.[6]

Beach restoration

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.

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.

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.[7]

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 will be used at a planned facility in St. Lucie County, Florida.[8]

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.

Environmental legislation

A map of reclaimed land in Hong Kong: Grey (built), red (proposed or under development). Most of the urban areas of Hong Kong are on reclaimed land.

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 in 1996 in an effort to safeguard the increasingly threatened Victoria Harbour against encroaching land development.[9]

Dangers

Reclaimed land is highly susceptible to soil liquefaction during earthquakes,[10] 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.

Land amounts added

  • Netherlands - about 1/6 of the entire country, or about 7,000 km2 in total, has been reclaimed from the sea, lakes, marshes and swamps.
  • South Korea - As of 2006, 38 percent or 1,550 km2 of coastal wetlands reclaimed, including 400  km2 at Saemangeum.
  • Singapore - 20% of the original size or 135 km2. As of 2003, plans for 99 km2 more are to go ahead,[11] despite the fact that disputes persist with Malaysia over Singapore's extensive land reclamation works.[12]
  • Hong Kong - (Main article: Land reclamation in Hong Kong)
Praya Reclamation Scheme began in the late 1860s and consisted of two stages totaling 50 to 60+ acres.[3] 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,[13] as well as the collusion of the Hong Kong Government with the real estate developers in the territory.[14][15]
In addition, as the city expands, new towns in different decades were mostly built on reclaimed land, such as Tuen Mun, Tai Po, Shatin-Ma On Shan, West Kowloon, Kwun Tong and Tseung Kwan O.
  • Macau - 170% of the original size or 17 km2[16]
  • Mumbai - An archipelago of originally 7 separate islands were joined together by land reclamation over a span of five centuries. This was done to develop Mumbai as a harbour city.
  • Monaco - (Main article: Land reclamation in Monaco) - 0.41 km2 out of 2.05 km2, or 1/5 of Monaco comes from land taken from the sea, mainly in the neighborhoods of Fontvieille, La Condamine, and Larvotto/Bas Moulins.
  • Tokyo Bay, Japan - 249 km2[17] including the entirety of Odaiba artificial island.
  • Kobe, Japan - 23 km2 (1995).
  • Bahrain - 76.3% of original size of 410 km2(1931–2007).
  • New Zealand - significant areas of land totalling several hundred hectares have been reclaimed along the harbourfront of Auckland, Wellington and Dunedin. In Dunedin - which in its early days was nicknamed "Mudedin" - around 2.5 km2, 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.

See also

External links

Notes

  1. ^ "American Society for Mining and Reclamation". Retrieved 2012-04-01.
  2. ^ Powter, Chris (2002). "Glossary of Reclamation and Remediation Terms used in Alberta" (PDF). Government of Alberta. ISBN 0-7785-2156-7. Retrieved 2012-04-01.
  3. ^ a b Bard, Solomon. [2002] (2002). Voices from the Past: Hong Kong 1842-1918. HK University press. ISBN 962-209-574-7
  4. ^ Petry, Anne K. (July 2003). "Geography of Japan" (PDF). Japan Digest, Indiana University. Retrieved 2009-07-30.
  5. ^ See for example Daniel R. Curtis, 'Into the frontier: medieval land reclamation and the creation of new societies. Comparing Holland and the Po Valley, 800-1500', http://academia.edu/1932594/Into_the_frontier_medieval_land_reclamation_and_the_creation_of_new_societies._Comparing_Holland_and_the_Po_Valley_800-1500
  6. ^ http://www.ogata.or.jp/english/history.html
  7. ^ 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
  8. ^ "Florida county plans to vaporize landfill trash". USA Today. 2006-09-09. Retrieved 2010-05-07.
  9. ^ Wallis, Keith (February 12, 1996). "Bill seeks to protect harbour". Hong Kong Standard. Retrieved 2007-03-23.
  10. ^ http://www.abag.ca.gov/bayarea/eqmaps/liquefac/Lq_rept.pdf
  11. ^ "Singapore Finds it Hard to Expand Without Sand". Planet Ark. Retrieved 2007-03-23.
  12. ^ "Singapore". The World Factbook. CIA. 1 September 2010. section Transnational issues. Retrieved 1 October 2010. disputes persist with Malaysia over […] extensive land reclamation works
  13. ^ "Courts protect our imperiled waterway - at least for the time being". Hong Kong Standard. August 14, 2006. Retrieved 2007-03-23.
  14. ^ DeGolyer, Michael (March 15, 2007). "Commentary: Just Looking for Answers". Hong Kong Standard. Retrieved 2007-03-23.
  15. ^ Ng, Michael (October 5, 2006). "Lawmaker warns of West Kowloon arts venue glut". Hong Kong Standard. Retrieved 2007-03-23.
  16. ^ http://www.gov.mo
  17. ^ "Japan Fact Sheet". Japan Reference. Retrieved 2007-03-23.

References

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