Editing Irrigation (section)

===Modern history===
The scale of global irrigation increased dramatically over the 20th century. In 1800, 8 million hectares were irrigated; in 1950, 94 million hectares, and in 1990, 235 million hectares. By 1990, 30% of the global food production came from irrigated land.<ref name="ReferenceD"/> Irrigation techniques across the globe included canals redirecting surface water,<ref name="ReferenceE"/><ref name="Peterson 2016"/> groundwater pumping, and diverting water from dams. National governments led most irrigation schemes within their borders, but private investors<ref name="ReferenceF"/> and other nations,<ref name="Peterson 2016"/> especially the [[United States]],<ref name="ReferenceG"/> [[China]],<ref name="ReferenceH"/> and European countries like the [[United Kingdom]],<ref name="ReferenceA"/> funded and organized some schemes within other nations. Irrigation enabled the production of more crops, especially [[cash crop|commodity crops]] in areas that otherwise could not support them. Countries frequently invested in irrigation to increase [[wheat]], [[rice]], or [[cotton]] production, often with the overarching goal of increasing self-sufficiency.<ref name="ReferenceA"/> In the 20th century, global anxiety, specifically about the American cotton monopoly, fueled many empirical irrigation projects: Britain began developing irrigation in [[India]], the [[Ottoman Empire|Ottomans]] in [[Egypt]], the [[France|French]] in [[Algeria]], the [[Portugal|Portuguese]] in [[Angola]], the [[Germany|Germans]] in [[Togo]], and [[Soviet Union|Soviets]] in [[Central Asia]].<ref name="Peterson 2016"/>

Negative impacts frequently accompany extensive irrigation. Some projects that diverted surface water for irrigation dried up the water sources, which led to a more extreme regional climate.<ref name="ReferenceB"/> Projects that relied on groundwater and pumped too much from underground aquifers created [[groundwater-related subsidence|subsidence]] and [[freshwater salinization|salinization]]. Salinization of irrigation water damaged the crops and seeped into drinking water.<ref name="ReferenceB"/> Pests and pathogens also thrived in the irrigation canals or ponds full of still water, which created regional outbreaks of diseases like [[malaria]] and [[schistosomiasis]].<ref name="McNeill 200"/><ref name="ReferenceI"/><ref name="ReferenceJ"/> Governments also used irrigation schemes to encourage migration, especially of more desirable populations into an area.<ref name="Parker 2020"/><ref name="Visser 2018"/><ref name="ReferenceK"/> Additionally, some of these large nationwide schemes failed to pay off at all, costing more than any benefit gained from increased crop yields.<ref name="ReferenceL"/><ref name="McNeill 2000"/>

====American West====
Irrigated land in the [[United States]] increased from 300,000 acres in 1880 to 4.1 million in 1890 to 7.3 million in 1900.<ref name="McNeill 2000" /> Two thirds of this irrigation sources from [[groundwater]] or small ponds and [[reservoirs]], while the other one third comes from large [[dam]]s.<ref>[[#refMcCully2001|McCully 2001]] p. 166.</ref> One of the main attractions of irrigation in the West was its increased dependability compared to rainfall-watered agriculture in the East. Proponents argued that farmers with a dependable water supply could more easily get loans from bankers interested in this more predictable farming model.<ref>[[#refWorster1992|Worster 1992]] pp.114-15.</ref> Most irrigation in the [[Great Plains]] region derived from underground [[aquifer]]s. Euro-American farmers who colonized the region in the 19th century tried to grow the commodity crops that they were used to, like [[wheat]], [[maize|corn]], and [[alfalfa]], but rainfall stifled their growing capacity. Between the late 1800s and the 1930s, farmers used [[windpump|wind-powered pumps]] to draw groundwater. These windpumps had limited power, but the development of gas-powered pumps in the mid-1930s pushed wells deep into the [[Ogallala Aquifer]]. Farmers irrigated fields by laying pipes across the field with [[irrigation sprinkler|sprinklers]] at intervals, a labor-intensive process, until the advent of the [[center pivot irrigation|center-pivot sprinkler]] after World War II, which made irrigation significantly easier.<ref>{{Citation |title=How Center Pivot Irrigation Brought the Dust Bowl Back to Life |url=https://www.smithsonianmag.com/innovation/how-center-pivot-irrigation-brought-dust-bowl-back-to-life-180970243/ |access-date=6 May 2022}}</ref> By the 1970s farmers drained the aquifer ten times faster than it could recharge, and by 1993 they had removed half of the accessible water.<ref>[[#refMcNeill2000|McNeill 2000]] pp. 151-52</ref>

Large-scale federal funding and intervention pushed through the majority of irrigation projects in the West, especially in [[California]], [[Colorado]], [[Arizona]], and [[Nevada]]. At first, plans to increase irrigated farmland, largely by giving land to farmers and asking them to find water, failed across the board. Congress passed the [[Desert Land Act]] in 1877 and the [[Carey Act]] in 1894, which only marginally increased irrigation.<ref>[[#refWorster1992|Worster 1992]] pp.156-157.</ref> Only in 1902 did Congress pass the [[Newlands Reclamation Act|National Reclamation Act]], which channeled money from the sale of western public lands, in parcels up to 160 acres large, into irrigation projects on public or private land in the arid West.<ref>[[#refWorster1992|Worster 1992]] p. 161.</ref> The Congressmen who passed the law and their wealthy supporters supported Western irrigation because it would increase American exports, 'reclaim' the West, and push the Eastern poor out West for a better life.<ref>[[#refWorster1992|Worster 1992]] pp.166-67.</ref>

While the National Reclamation Act was the most successful piece of federal irrigation legislation, the implementation of the act did not go as planned. The [[United States Bureau of Reclamation|Reclamation Service]] chose to push most of the Act's money toward construction rather than settlement, so the Service overwhelmingly prioritized building large dams like the [[Hoover Dam]].<ref>[[#refPisani2002|Pisani 2002]] p.30.</ref> Over the 20th century, Congress and state governments grew more frustrated with the Reclamation Service and the irrigation schemes. [[Frederick Haynes Newell|Frederick Newell]], head of the Reclamation Service, proving uncompromising and challenging to work with, falling crop prices, resistance to delay debt payments, and refusal to begin new projects until the completion of old ones all contributed.<ref>[[#refPisani2002|Pisani 2002]] p.152.</ref> The [[Reclamation Extension Act of 1914]], transferring a significant amount of irrigation decision-making power regarding irrigation projects from the Reclamation Service to Congress, was in many ways a result of increasing political unpopularity of the Reclamation Service.<ref>[[#refPisani2002|Pisani 2002]].</ref>

In the lower [[Colorado River|Colorado Basin]] of [[Arizona]], [[Colorado]], and [[Nevada]], the states derive irrigation water largely from rivers, especially the [[Colorado River]], which irrigates more than 4.5 million acres of land, with a less significant amount coming from groundwater.<ref>{{Citation |title=Colorado River Basin Studies |date=March 24, 2022 |url=https://www.usgs.gov/centers/utah-water-science-center/science/colorado-river-basin-studies |access-date=6 May 2022}}</ref> In the 1952 case [[Arizona v. California]], Arizona sued California for increased access to the Colorado River, under the grounds that their groundwater supply could not sustain their almost entirely irrigation-based agricultural economy, which they won.<ref>{{cite book |title=Dividing western waters: Mark Wilmer and Arizona v. California |vauthors=August JL |date=2007 |publisher=TCU Press}}</ref> California, which began irrigating in earnest in the 1870s in [[San Joaquin Valley]],<ref>[[#refWorster1992|Worster 1992]] p. 102.</ref> had passed the [[Wright Act of 1887]] permitting agricultural communities to construct and operate needed irrigation works.<ref>[[#refWorster1992|Worster 1992]] p. 108.</ref> The Colorado River also irrigates large fields in California's [[Imperial Valley]], fed by the National Reclamation Act-built All-American Canal.<ref>[[#refMcNeill2000|McNeill 2000]] p. 178</ref><ref>[[#refWorster1992|Worster 1992]] p.208.</ref>

====Soviet Central Asia====
When the [[Bolsheviks]] conquered [[Soviet Central Asia|Central Asia]] in 1917, the native [[Kazakhs]], [[Uzbeks]], and [[Turkmens]] used minimal irrigation. The Slavic immigrants pushed into the area by the Tsarist government<ref>{{Citation |title=Slavic peasant settlers in Russian Turkestan, 1886-1917 |url=https://ora.ox.ac.uk/objects/uuid:5c4e60e0-12a8-442c-ade8-ac43e403afc6/files/m9da4614a83470507950e0f86166d3968 |access-date=6 May 2022 |vauthors=Morrison A}}</ref> brought their irrigation methods, including waterwheels, the use of [[paddy fields|rice paddies]] to restore salted land, and underground irrigation channels. Russians dismissed these techniques as crude and inefficient. Despite this, tsarist officials maintained these systems through the late 19th century without other solutions.<ref name="ReferenceC">[[#refPeterson2016|Peterson 2016]].</ref>

Before conquering the area, the Russian government accepted a 1911 American proposal to send hydraulic experts to Central Asia to investigate the potential for large-scale irrigation. A 1918 decree by [[Lenin]] then encouraged irrigation development in the region, which began in the 1930s. When it did, [[Joseph Stalin|Stalin]] and other Soviet leaders prioritized large-scale, ambitious hydraulic projects, especially along the [[Volga|Volga River]]. The Soviet irrigation push stemmed mainly from their late 19th century fears of the American cotton monopoly and subsequent desire to achieve cotton self-sufficiency.<ref>[[#refMcNeill2000|McNeill 2000]] p. 163</ref> They had built up their textile manufacturing industry in the 19th century, requiring increased cotton and irrigation, as the region did not receive enough rainfall to support cotton farming.<ref name="ReferenceC" />

The Russians built dams on the [[Don (river)|Don]] and [[Kuban (river)|Kuban]] Rivers for irrigation, removing freshwater flow from the [[Sea of Azov]] and making it much saltier. Depletion and salinization scourged other areas of the Russian irrigation project. In the 1950s, Soviet officials began also diverting the [[Syr Darya]] and the [[Amu Darya]], which fed the [[Aral Sea]]. Before diversion, the rivers delivered {{convert|55|km3|cumi|0}} of water to the Aral Sea per year, but after, they only delivered {{convert|6|km3|cumi|1}}. Because of its reduced inflow, the Aral Sea covered less than half of its original seabed, which made the regional climate more extreme and created airborne salinization, lowering nearby crop yields.<ref>[[#refMcNeill2000|McNeill 2000]] pp. 164-5</ref>

By 1975, the USSR used eight times as much water as they had in 1913, mostly for irrigation. Russia's expansion of irrigation began to decrease in the late 1980s, and irrigated hectares in Central Asia capped out at 7 million. [[Mikhail Gorbachev]] killed a proposed plan to reverse the Ob and Yenisei for irrigation in 1986, and the breakup of the USSR in 1991 ended Russian investment in Central Asian cotton irrigation.<ref>[[#refMcNeill2000|McNeill 2000]] p. 166</ref>

====Africa====
Different irrigation schemes with various goals and success rates have been implemented across Africa in the 20th century but have all been influenced by colonial forces. The [[Tana River (Kenya)|Tana River]] Irrigation Scheme in eastern [[Kenya]], completed between 1948 and 1963, opened up new lands for agriculture. The Kenyan government attempted to resettle the area with detainees from the [[Mau Mau rebellion|Mau Mau uprising]].<ref>[[#refParker2020|Parker 2020]].</ref> Italian oil drillers discovered Libya's underground water resources during the [[Italian colonization of Libya]]. This water lay dormant until 1969, when [[Muammar Gaddafi|Muammar al-Gaddafi]] and American [[Armand Hammer]] built the [[Great Man-Made River]] to deliver the Saharan water to the coast. The water largely contributed to irrigation but cost four to ten times more than the crops it produced were worth.<ref>[[#refMcNeill2000|McNeill 2000]] p. 155</ref>

In 1912, the [[Union of South Africa]] created an irrigation department and began investing in water storage infrastructure and irrigation. The government used irrigation and dam-building to further social goals like poverty relief by creating construction jobs for poor whites and irrigation schemes to increase white farming. One of their first significant irrigation projects was the [[Hartbeespoort Dam]], begun in 1916 to elevate the living conditions of the 'poor whites' in the region and eventually completed as a 'whites only' employment opportunity.<ref>{{cite book |url=https://muse.jhu.edu/book/60573 |title=White South Africa's 'weak sons': Poor whites and the Hartbeespoort Dam |vauthors=Clynick T |date=2007 |publisher=Wits University Press |isbn=978-1-86814-669-7 |veditors=Esterhuysen A, Jenkins T, Bonner P |pages=248–274 |chapter=A Search for Origins: Science, history and South Africa's "Cradle of Humankind"}}</ref> The [[Pretoria]] irrigation scheme, [[Kammanassie Dam|Kammanassie project]], and Buchuberg irrigation scheme on the [[Orange River]] all followed in the same vein in the 1920s and 30s.<ref name="Visser 2018" />

In Egypt, modern irrigation began with [[Muhammad Ali of Egypt|Muhammad Ali Pasha]] in the mid-1800s, who sought to achieve Egyptian independence from the [[Ottoman Empire|Ottomans]] through increased trade with Europe—specifically cotton exportation.<ref>[[#refRoss2017|Ross 2017]] p. 33.</ref> His administration proposed replacing the traditional [[flooding of the Nile|Nile basin irrigation]], which took advantage of the annual ebb and flow of the Nile, with irrigation barrages in the lower Nile, which better suited cotton production. Egypt devoted 105,000 ha to cotton in 1861, which increased fivefold by 1865. Most of their exports were shipped to England, and the United States Civil War-induced cotton scarcity in the 1860s cemented Egypt as England's cotton producer.<ref>[[#refRoss2017|Ross 2017]] p. 32.</ref> As the Egyptian economy became more dependent on cotton in the 20th century, controlling even small Nile floods became more important. Cotton production was more at risk of destruction than more common crops like [[barley]] or wheat.<ref>[[#refMcNeill2000|McNeill 2000]] p. 167</ref> After the [[history of Egypt under the British|British occupation of Egypt in 1882]], the British intensified the conversion to perennial irrigation with the construction of the [[Delta Barrage]], the [[Assiut Barrage]], and the first [[Aswan Low Dam|Aswan Dam]]. Perennial irrigation decreased local control over water and made traditional subsistence farming or the farming of other crops incredibly difficult, eventually contributing to widespread peasant bankruptcy and the [['Urabi revolt|1879-1882 'Urabi revolt]].<ref>[[#refRoss2017|Ross 2017]] p. 37-38.</ref>