View source for Chu River

:''"Chui River" and "Chuy River" redirect here. For the river of Anhui see [[Chu River (Anhui)]]. For the South American Chuí or Chuy River, on the Brazil-Uruguay border and Brazil's southernmost point, see [[Chuí Stream]]. For the Nam Sam River or Chu River, on the Lao-Vietnam border, see [[Nam Sam River]].''
{{Geobox|River
<!-- *** Name section *** -->  
| name                        = Chu River
| native_name                 = Чу, Чүй, Шу
| other_name                  = 
| other_name1                 =
| category_hide = 1
<!-- *** Image *** --->
| image                       = E8115-Chu-Valley.jpg
| image_size                  = 250
| image_caption               = In the Chuy Valley below [[Tokmok]]
<!-- *** Etymology *** --->
| etymology                   = 
<!-- *** Country etc. *** -->
| country                     = [[Kyrgyzstan]] 
| country1                    = [[Kazakhstan]]
| state                       = 
| state1                      = 
| region                      = 
| region1                     =
| district                    = 
| district1                   = 
| city                        = 
| city1                       = 
| landmark                    = 
| landmark1                   = 
<!-- *** Geography *** -->
| length                      = 1067
| watershed                   = 67500
| discharge_location          = 
| discharge                   = 
| discharge_max               = 
| discharge_min               = 
| discharge1_location         = 
| discharge1                  = 
<!-- *** Source *** -->
| source_name                 = confluence of [[Joon Aryk]] and [[Kochkor River]]
| source_location             = 
| source_district             = [[Kochkor District]]
| source_region               = [[Naryn Region]]
| source_state                = 
| source_country              = [[Kyrgyzstan]]
| source_lat_d                = 42
| source_lat_m                = 13
| source_lat_s                = 15.60
| source_lat_NS               = N
| source_long_d               = 75
| source_long_m               = 44
| source_long_s               = 29
| source_long_EW              = E
| source_elevation            = 1802
| source_length               = 
<!-- *** Mouth *** -->
| mouth_name                  = Akjaykyn system of lakes
| mouth_location              = 
| mouth_district              = 
| mouth_region                = [[South Kazakhstan Region]]
| mouth_state                 = 
| mouth_country               = [[Kazakhstan]]
| mouth_lat_d                 = 44
| mouth_lat_m                 = 59
| mouth_lat_s                 = 
| mouth_lat_NS                = N
| mouth_long_d                = 67
| mouth_long_m                = 43
| mouth_long_s                = 
| mouth_long_EW               =E
| mouth_elevation             = 135
<!-- *** Tributaries *** -->
| tributary_left              = [[Ala-Archa River]]
| tributary_left1             = [[Kara-Balta River]]
| tributary_left2             = [[Ysyk-Ata River]]
| tributary_left3             = [[Alamudun River]]
| tributary_left4             = [[Ak-Suu River (Chu)|Ak-Suu River]]
| tributary_right             = [[Chong-Kemin River]]
| tributary_right1            = [[Kichi-Kemin River]]
| tributary_right2            =
| tributary_right3            =
| tributary_right4            =
<!-- *** Free fields *** -->
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<!-- *** Map section *** -->
| Map                         = 
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| map_caption                 =
}}

The '''Chu''' ('''Shu''' or '''Chui''', '''Chuy''') ({{lang-kk|Шу}}/Şuw, شۋ; {{lang-ky|Чүй}}, ''Çüy'', چۉي; {{lang-dng|Чў}}, ''Çw''; {{lang-ru|''Чу''}}) is a river in northern [[Kyrgyzstan]] and southern [[Kazakhstan]]. Of the length of approximately 1&nbsp;067&nbsp;kilometres<ref>[[Great Soviet Encyclopedia]]</ref> (663 miles), the first 115 kilometres are in Kyrgyzystan, then for 221 kilometres the river is the border between Kyrgyzystan and Kazakhstan, and the last 731 kilometres are in Kazakhstan. It's one of the longest [[river]]s in Kyrgyzstan and in Kazakhstan.

[[Chuy Region]], the northernmost and most populous administrative region of Kyrgyzstan, is named after the river; so are the Chuy Avenue, the main street of Bishkek, and the city of [[Shu, Jambyl|Shu]] in Kazakhstan's [[Jambyl Region]].

==Course==

The '''Chu River''' is formed by the confluence of rivers [[Joon Aryk]] and [[Kochkor River|Kochkor]] in [[Kochkor District]] of [[Naryn Region]]. After approaching Lake [[Issyk Kul]] within a few kilometers (near [[Balykchy]]), without either flowing into the lake or draining it, it turns to the northwest. In the 1950s an old riverbed called Ketmaldy (also Buugan) linked the Chu River and Issyk Kul. During floods part of Chu water would reach the lake, but such outflow has not be seen since construction of the [[Orto-Tokoy Reservoir]]. After passing through the narrow [[Boom Gorge]] ({{lang-ru|Боомское ущелье}}, ''Boomskoye ushchelye''), the river enters the comparatively flat [[Chuy Valley]], within which the Kyrgyz capital of [[Bishkek]] and the Kazakh city of [[Shu, Jambyl|Shu]] are located. Much of the Chu's water is diverted into a network of canals to irrigate the fertile black soils of the Chuy Valley for farming, both on the Kyrgyz and Kazakh sides of the river.

As the Chu flows through the Chuy Valley, it forms the border between Kyrgyzstan and Kazakhstan for more than a hundred kilometers, but then it leaves [[Kyrgyzstan]] and flows into [[Kazakhstan]], where, like many other rivers and streams that drain northern Kyrgyzstan it eventually disappears in the [[steppe]], short of reaching the [[Syr Darya]], although it has sometimes reached that river in wet years.

==History==
[[File:Syrdaryamap.png|thumb|right|300px|Chu River in the Syr Darya basin]]
The area of this river was originally home to the [[Iranian peoples|Iranian]] [[Sughd]]s who spoke [[Soghdian]], an East [[Iranian language]].<ref name="barthold">{{cite book
 | last = Barthold
 | first = W.
 | title = "Balāsāg̲h̲ūn or Balāsaḳūn." Encyclopaedia of Islam.
 | edition = 
 | year = 
 | month = 
 | publisher = Brill Academic Publishers
 | location = Brill Online. Universiteitsbibliotheek Leiden
 | url = http://www.brillonline.nl/subscriber/entry?entry=islam_SIM-1131
 | pages = 
 |  accessdate = 
}}</ref>

During the [[Middle Ages]], the area was strategically important. It was the setting of [[Suayub]], the capital of the [[Western Turkic Khaganate]], and [[Balasagun]], the capital of the [[Kara-Khitan]]s.

Chu River posed a risk of flooding for settlements located in Chu Valley. In winter 1878, an ice gorge formed on Chu River upstream town [[Tokmok]] that was the center of Semirechye Province. This was followed by severe flooding that damaged the town and the center of the province was moved to Pishpek (Bishkek). After this, Tokmak gradually lost its significance.<ref name="flooding">{{cite web
| url= http://www.citykr.kg/tokmok.php#ser1| title = Profile of town Tokmok (in Russian)| accessdate = 2010-03-10}}</ref>

==Dams==
The river flow is regulated by the dam at Orto-Tokoy Reservoir in Kyrgyzstan built in 1957, and the dam at Tasotkel Reservoir in Kazakhstan built in 1974.

==Ecology and environment==

===Environmental monitoring===
The Kyrgyz State Agency on Hydrometeorology and Kazakhstan Hydrometeorological Service (Kazhydromet) operate a number of water quality monitoring stations on the Chu River and its tributaries.<ref name="envmonitoring">{{cite web
 |url=http://www.meteo.ktnet.kg/unzps/unzps_voda_arch.php 
 |title=Kyrgyz State Agency on Hydrometeorology: water quality 
 |accessdate=2010-03-10 
 |deadurl=yes 
 |archiveurl=https://web.archive.org/web/20110722132012/http://www.meteo.ktnet.kg/unzps/unzps_voda_arch.php 
 |archivedate=2011-07-22 
 |df= 
}}</ref>

===Water quality===
According to Kyrgyz State Agency on Hydrometeorology, in 2004–08, water pollution index of the Chu River in Chu Valley ranged from 0.25 to 0.7 units that is interpreted as Class II ("Clean water"). The only exception was a monitoring point downstream Vasilyevka village where water pollution index ranged from 0.4 to 1.2 unit and water quality was assessed as Class II(Clean)/Class III ("Moderately polluted").<ref name="envmonitoring" />

According to Kazakhstan Hydrometeorological Service (Kazhydromet), water pollution index of Shu (Chu) River in [[Jambyl Region]] of Kazakhstan amounted to 2.01 (Class III, "Moderately polluted") in 2008, and 1.83 (Class III, "Moderately polluted") in 2009. Such water quality parameters as [[biochemical oxygen demand]], [[nitrite]]s, [[copper]], [[phenols]] exceeded the maximum allowable concentrations.<ref name="waterpollution">{{Cite report |title=Information Bulletin on Status of the Environment in the Republic of Kazakhstan in 2009 |url=http://www.eco.gov.kz/ekolog/buleten/bul_2009.rar |author=Department of Ecological Monitoring |last= |first= |coauthors= |year=2010 |publisher=Ministry of Environment Protection of the Republic of Kazakhstan |accessdate= |docket= }}</ref>

==Major tributaries==
In Kyrgyzstan, 4892 rivers and canals flow into Chu River.<ref name="encyc">{{cite book
|title=Чүй облусу:Энциклопедия
|trans_title=Encyclopedia of Chuy Oblast
|first=
|last=
|publisher=Chief Editorial Board of Kyrgyz Encyclopedia
|language=Kyrgyz, Russian
|location=Bishkek
|year=1994
|isbn=5-89750-083-5
|pages=718
}}</ref> The list of the major tributaries include:
*
* [[Chong-Kemin River]]
* [[Kichi-Kemin River]]
* [[Kara-Konuz River]]
* [[Shamshy River]]
* [[Ysyk-Ata River]]
* [[Alamudun River]]
* [[Ala-Archa River]]
* [[Jylamysh River]]
* [[Ak-Suu River (Chu)|Ak-Suu River]]
* [[Kara-Balta River]]

==Gallery==
<gallery>
Image:E8145-Chu-River.jpg|In the [[Boom Gorge]]
Image:balbal.jpg|A medieval [[balbal]] near [[Burana Tower]] in the Chuy Valley
Image:E8046-Chuy-Valley-Milyanfan-east.jpg|In the Chuy Valley near [[Milyanfan]]
Image:E7858-Korday-Chu.jpg|Near [[Korday]] border crossing
Image:E7840-Shu-city-river-crossing.jpg|Near [[Shu, Jambyl|Shu]], Kazakhstan
</gallery>

==References==
<references/>

{{commons category|Chu River}}

{{Rivers of Kazakhstan}}
{{Rivers of Kyrgyzstan}}

{{Authority control}}

[[Category:Rivers of Kyrgyzstan]]
[[Category:Rivers of Kazakhstan]]
[[Category:Issyk-Kul Region]]
[[Category:Chuy Region]]
[[Category:Border rivers]]
[[Category:Jambyl Region]]
[[Category:Kazakhstan–Kyrgyzstan border]]
[[Category:International rivers of Asia]]