land reclamation

 

practice of converting land deemed unproductive into arable land by such methods as irrigation, drainage, flood control, altering the texture and mineral and organic content of soil (see fertilizer), and checking erosion. In the United States, all these methods have been used, but the chief effort has been through irrigation. Under the Reclamation Act of 1902, the Bureau of Reclamation supplies water, subsidized by taxpayers, to farmers on arid lands in 17 western states (see Reclamation, United States Bureau of). The irrigation water has increased production, but at some cost: selenium and salinity poisoning have damaged land once reclaimed, competition has grown between agriculture and municipal interests, and wildlife habitat has been jeopardized. Additional aims of the reclamation program include hydroelectric power generation, recreation, and flood control.

History of Reclamation in the United States

While irrigation schemes were built in the Southwest before the coming of the Spanish, by the Catholic missions in California, and by Mormons in Utah by 1847, moves to gain government help for reclamation schemes began with the Carey Land Act (1894). Focusing on the conservation of natural resources during the presidency of Theodore Roosevelt, reclamation was advocated for lands ruined by injudicious farming, grazing, and deforestation as well as for lands with little rainfall.

The Reclamation Act of 1902 provided that the federal government should plan and construct irrigation projects using the proceeds of public land sales, and that the water users (usually organized in some type of cooperative) should liquidate the cost and purchase the irrigation works over a period of 10 years. The program was vigorously pushed by Secretary of the Interior Ethan Allen Hitchcock. Among the many projects started then were the Truckee-Carson project (see Newlands project) and the Salt River project (see Salt River valley). The 1902 act had an acreage-limitation provision, but it did not halt the process of speculation in lands to be irrigated, which made costs to the actual farmers prohibitive. In 1914 the period of time for the water users to pay for the project was lengthened to 20 years (later raised to 40 years).

Interest in reclamation quickened after terrible droughts in the late 1920s and early 30s, and in the public works program of the New Deal under Franklin D. Roosevelt the reclamation program was linked with projects for flood control and for the development of power. The Bureau of Reclamation began to work alongside the U.S. Army Engineers Corps in building dams and forwarding multipurpose projects. The Flood Control Act of 1944 broadened the powers of the federal government in these matters.

Reclamation has created much new wealth in the United States by turning areas that had formerly been arid into thriving agricultural and industrial communities. However, environmentalists have questioned and even stopped more recent projects, such as the Bureau's 1991 water project on the Colorado River, due to the damage to the environment such dam building has caused. The Columbia River complex has had to limit the amount of water diverted to safeguard spawning salmon, and the Omnibus Water Bill of 1992 limited the bureau to environmentally sound projects. Further, criticism that the bureau's programs have disproportionately aided large, rich farms led, in the 1992 bill, to the restriction of water subsidies to family farms.

Bibliography

See F. Powledge, Water (1982); M. P. Reisner, Cadillac Desert (1986).

Land reclamation is either of two distinct practices. One involves creating new land from sea- or riverbeds, the other refers to restoring an area to a more natural state (such as after pollution or salination have made it unusable).

Creating new land

For habitation or agriculture

Land reclamation is the creation of new land where there was once water. Notable examples include parts of New Orleans; Washington, D.C. (which is partially built on land that was once swamp); Mexico City (which is situated at the former site of Lake Texcoco); Helsinki (of which the major part of the city center is built on reclaimed land); the Cape Town foreshore; the Chicago shoreline, the Manila Bay shoreline, Back Bay, Boston, Massachusetts; Battery Park City, Manhattan; the port of Zeebrugge Belgium and the polders of the Netherlands.

Japan, the southern Chinese cities of Hong Kong and Macau and the city-state of Singapore, where land is in short supply, are also famous for their efforts on land reclamation. One of the earliest and famous project was the Praya Reclamation Scheme, which added 50 to 60 acres of land in 1890 during the second phase of construction. It was one of the most ambitious project ever taken during the Colonial Hong Kong era.^[1] Some 20% of land in the Tokyo Bay area has been reclaimed^[2]. Monaco and the British territory of Gibraltar are also expanding due to land reclamation. The city of Rio de Janeiro was largely built on reclaimed land.

Artificial islands are an example of land reclamation. Creating an artificial island is an expensive and risky undertaking. It is often considered in places that are densely populated and flat land is scarce. 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.

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 productive use of land that would otherwise be restricted to wildlife habitat. It is also an important method of mosquito control.

For 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.

Repairing damaged land

Land reclamation or Land rehabilitation is also the process of cleaning up a site that has sustained environmental degradation, such as strip mining. This can be done to allow for some form of human use (such as a housing development) or to restore that area back to its natural state as a wildlife habitat home.

Environmental impact

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

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^[3].

Land amounts added

• Netherlands -about 1/5 land from land reclamation
• Singapore - 20% of the original size or 135 km² as of 2003, plans for 99 km² more^[4].
• Hong Kong - Praya Reclamation Scheme began in the late 1860s that consisted of two stage totaling 50 to 60+ acres^[1][5]. This figure understates the importance of the sites reclaimed: 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^[6], as well as the collusion of the Hong Kong Government with the real estate developers in the territory^[7][8].
• Macau - 170% of the original size or 17 km² ^[1]
• Tokyo Bay, Japan - 249 km²^[9].
• Kobe, Japan - 23 km² (1995).

References

See also

• Land rehabilitation
• United States Bureau of Reclamation
• Land improvement
• Hong Kong Society for Protection of the Harbour

External links

• Reclamation of waterlogged and saline soils, provides free downloads of software and articles on land drainage.
• Trek Construction & Environmental Services Ltd., provides reclamation services to the upstream Oil & Gas Industry.
• Youcanchangetheplanet.org - A non-profit organization dedicated to sustainable conservation and the rehabilitation of damaged ecosystems.

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