Editing Canal (section)

===Ancient canals===
{{See also|List of Roman canals|Qanat}}
The oldest known canals were [[irrigation]] canals, built in [[Mesopotamia]] {{circa|4000 BC}}, in what is now [[Iraq]]. The [[Indus Valley civilization]] of [[ancient India]] ({{circa|3000 BC}}) had sophisticated irrigation and storage systems developed, including the [[reservoir]]s built at [[Girnar]] in 3000 BC.<ref>{{Harvnb|Rodda|2004|p=161.}}</ref> This is the first time that such planned civil project had taken place in the ancient world. In [[Egypt]], canals date back at least to the time of [[Pepi I Meryre]] (reigned 2332–2283 BC), who ordered a canal built to bypass the [[Cataracts of the Nile|cataract]] on the Nile near [[Aswan]].<ref>{{Harvnb|Hadfield|1986|p=16.}}</ref>
[[File:Xu Yang - Junks on the canal.jpg|thumb|right|The [[Grand Canal of China]] at [[Suzhou, Jiangsu|Suzhou]]]]
In [[History of China#Ancient China|ancient China]], large canals for river transport were established as far back as the [[Spring and Autumn period]] (8th–5th centuries BC), the longest one of that period being the Hong Gou (Canal of the Wild Geese), which according to the ancient historian [[Sima Qian]] connected the old states of Song, Zhang, Chen, Cai, Cao, and Wei.<ref>{{Harvnb|Needham|1971|p=269.}}</ref> The [[Caoyun System]] of canals was essential for imperial taxation, which was largely assessed in kind and involved enormous shipments of rice and other grains. By far the longest canal was the [[Grand Canal of China]], still the longest canal in the world today and the oldest extant one.<ref name="Langmead">{{cite book|author=Donald Langmead|title=Encyclopedia of Architectural and Engineering Feats|url=https://archive.org/details/encyclopediaofar0000lang|url-access=registration|access-date=15 February 2013|publisher=ABC-CLIO|isbn=978-1-57607-112-0|page=[https://archive.org/details/encyclopediaofar0000lang/page/37 37]|quote=the world's largest artificial waterway and oldest canal still in existence|year=2001}}</ref> It is {{convert|1794|km|mi}} long and was built to carry the [[Emperor Yang of Sui|Emperor Yang Guang]] between Zhuodu ([[Beijing]]) and Yuhang ([[Hangzhou]]). The project began in 605 and was completed in 609, although much of the work combined older canals, the oldest section of the canal existing since at least 486 BC. Even in its narrowest urban sections it is rarely less than {{convert|30|m|ft}} wide.

In the 5th century&nbsp;BC, [[Achaemenid]] king [[Xerxes I]] of Persia ordered the construction of the [[Xerxes Canal]] through the base of [[Mount Athos]] peninsula, [[Chalkidiki]], northern Greece.<ref name="VII, 22">Herodotus [https://www.perseus.tufts.edu/hopper/text?doc=Hdt.+7.22 VII, 22]</ref> It was constructed as part of his preparations for the [[Second Persian invasion of Greece]], a part of the [[Greco-Persian Wars]]. It is one of the few monuments left by the Persian Empire in [[Europe]].<ref name="BSA98">B. S. J. Isserlin, R. E. Jones, V. Karastathis, S. P. Papamarinopoulos, G. E. Syrides and J. Uren "The Canal of Xerxes: Summary of Investigations 1991-2001" The Annual of the British School at Athens Vol. 98 (2003), pp. 369–385 {{JSTOR|30073214}}.</ref>

[[Greek engineering|Greek engineers]] were also among the first to use [[Lock (water transport)|canal locks]], by which they regulated the water flow in the [[Ancient Suez Canal]] as early as the 3rd century&nbsp;BC.<ref>Moore, Frank Gardner (1950): "Three Canal Projects, Roman and Byzantine", ''[[American Journal of Archaeology]]'', Vol. 54, No. 2, pp. 97–111 (99–101)</ref><ref name="Froriep 1986, 46">Froriep, Siegfried (1986): "Ein Wasserweg in Bithynien. Bemühungen der Römer, Byzantiner und Osmanen", ''Antike Welt'', 2nd Special Edition, pp. 39–50 (46)</ref><ref>Schörner, Hadwiga (2000): "Künstliche Schiffahrtskanäle in der Antike. Der sogenannte antike Suez-Kanal", ''Skyllis'', Vol. 3, No. 1, pp. 28–43 (33–35)</ref>
<blockquote>
There was little experience moving bulk loads by carts, while a pack-horse would [i.e. 'could'] carry only an eighth of a ton. On a soft road a horse might be able to draw 5/8ths of a ton. But if the load were carried by a barge on a waterway, then up to 30 tons could be drawn by the same horse.<br />— technology historian [[Ronald W. Clark]] referring to transport realities before the industrial revolution and the [[Canal age]].<ref name="WorksOfMan">''"Works of Man"'', [[Ronald W. Clark]], {{ISBN|0-670-80483-5}} (1985) 352 pages, Viking Penguin, Inc, New York, <br />quotation p. 87: "There was little experience moving bulk loads by carts, while a packhorse would [sic, meaning 'could' or 'can only'] carry only an eighth of a ton. On a soft road a horse might be able to draw 5/8ths of a ton. But if the load were carried by a barge on a waterway, then up to 30 tons could be drawn by the same horse.</ref></blockquote>

[[Hohokam]] was a society in the [[Indigenous peoples of the North American Southwest|North American Southwest]] in what is now part of [[Arizona]], United States, and [[Sonora]], Mexico. Their irrigation systems supported the largest population in the Southwest by 1300 CE.<ref name="AZMNH" /> Archaeologists working at a major archaeological dig in the 1990s in the Tucson Basin, along the Santa Cruz River, identified a culture and people that may have been the ancestors of the Hohokam.<ref>2007-036 General COP Treatment Plan; Pueblo Grande Museum Project 2007–95; City of Phoenix Project No. ST87350010; [http://phoenix.gov/webcms/groups/internet/@inter/@rec/@arts/@mus/@pueblo/documents/web_content/gentrtment.pdf#page=17 '''p. 9''' ''Cultural Context''] {{Webarchive|url=https://web.archive.org/web/20140324215827/http://phoenix.gov/webcms/groups/internet/@inter/@rec/@arts/@mus/@pueblo/documents/web_content/gentrtment.pdf#page=17 |date=March 24, 2014 }}</ref> This prehistoric group occupied southern Arizona as early as 2000 BCE, and in the Early Agricultural period grew corn, lived year-round in sedentary villages, and developed sophisticated irrigation canals.<ref name="AZMNH">{{cite web|title=The Hohokam|url=http://www.azmnh.org/arch/hohokam.aspx|publisher=Arizona Museum of Natural History, City of Mesa|access-date=November 30, 2012|url-status=dead|archive-url=https://web.archive.org/web/20121130091322/http://www.azmnh.org/arch/hohokam.aspx|archive-date=November 30, 2012|df=mdy-all}}</ref>
The large-scale Hohokam irrigation network in the [[Phoenix, Arizona|Phoenix metropolitan area]] was the most complex in ancient North America. A portion of the ancient canals has been renovated for the [[Salt River Project]] and now helps to supply the city's water.

[[File:Yodha Ela.jpg|thumb|Yodha Ela, [[Anuradhapura]], [[Sri Lanka]]]]
The [[Sinhalese people|Sinhalese]] constructed the 87&nbsp;km (54&nbsp;mi) [[Yodha Ela]] in 459 A.D. as a part of their [[Sri Lankan irrigation network|extensive irrigation network]] which functioned in a way of a moving reservoir due to its single banking aspect to manage the canal pressure with the influx of water. It was also designed as an elongated reservoir passing through traps creating 66 mini catchments as it flows from [[Kala Wewa]] to [[Tissa Wewa (Anuradhapura)|Thissa Wawa]]. The canal was not designed for the quick conveying of water from Kala Wewa to Thissa Wawa but to create a mass of water between the two reservoirs, which would in turn provide for agriculture and the use of humans and animals.<ref>{{Cite web|url=https://srilanka.travel/yoda-ela |title=Yoda Ela – An Ancient Engineering Marvel}}</ref>
<ref>{{cite book|title=Outlines of Ceylon History|isbn = 9788120613638|url=https://books.google.com/books?id=cDwvQF_OgvMC&q=yodha+ela&pg=PA77|last1 = Obeyesekere|first1 = Donald|year = 1999| publisher=Asian Educational Services }}</ref> They also achieved a rather low gradient for its time. The canal is still in use after renovation.