This article is about a river in Moscow, a tributary of the Moskva River. The Yauza (Russian: Яуза) is a river in Moscow and Mytishchi, Russia, a tributary of the Moskva River. It originates in the Losiny Ostrov National Park northeast of Moscow, flows through Mytishchi, enters Moscow in the Medvedkovo District and flows through the city in an irregular, meandering, generally north-south direction. The Yauza joins the Moskva River in Tagansky District just west of Tagansky Hill, now marked by the Kotelnicheskaya Embankment tower. Valleys of the Yauza, from the MKAD beltway in the north to the Moscow-Yaroslavl railway west of Sokolniki Park, are protected as natural reserves.^[1]

The Yauza has been mentioned in Russian chronicles since 1156;^[2] the exact origin of the name is unknown. Moscow crossed its former natural eastern boundary (marked by the Yauza) in the beginning of the 16th century.^[3] The banks of the Yauza within the Garden Ring were densely urbanized by the middle of the 17th century; upstream valleys housed suburban residences of the House of Romanov, from Mikhail to Catherine II.^[4] Settlements along the Yauza (German Quarter, Lefortovo, Preobrazhenskoye) played a significant role in the history of Russia in the 17th and 18th centuries.

Industrialization in the 19th and 20th centuries made the Yauza "the biggest gutter for waste in Moscow".^[5] In the 2000s the ecology improved, with the closing or conversion of old factories and cleanup efforts by the city government. In 2007 the Yauza waters were reclassified from "dirty" to "polluted" status,^[6] but in 2008 the trend reversed and pollution in the Yauza exceeded its 2006 levels.^[7] As of 2008, Yauza water passing the Moscow city boundary is rated as "polluted", and reaches a "very dirty" level at its inlet.^[8] Untreated surface runoff in the Central Administrative District remains the main source of pollution.^[9]

Contents   [hide]  1 Geology 2 Geography 3 History 3.1 Prehistory to the Time of Troubles 3.2 17th and 18th centuries 3.3 Industrialization 3.4 20th century 4 Ecology 5 See also 6 References 7 Sources

[Edit]Geology

Yauza is arguably one of the most ancient European rivers. Pre-Yauza first appeared in Permian-Triassic period, at which time it was flowing to the east of its present riverbed, down what is nowIzmailovo Gully. After being periodically submerged during Jurassic and Cretaceous periods, the region finally became land in Tertiary period. Due to minor elevation changes, Yauza changed its course to its present condition, while its former riverbed taken by present-day Serebryanka river, which is part of Yauza basin and flows in the westward direction opposite to original Yauza^[10].

[Edit]Geography

The contemporary Yauza consists of three parts:

The Upper Yauza flows from the marshes of Losiny Ostrov ( 55°52′40″N 37°53′19″E). The lakes surrounding the river ( 55°52′38″N 37°50′24″E) were formed in the 20th century on abandoned peat-mining sites.[11] A 1995 study identified twelve beaver colonies in the upper Yauza basin; large portions became a typical "beaver landscape".[11]

After the river enters the city of Mytischi, it flows through a chain of narrow valleys into Sokolniki Park deep inside Moscow.( 55°49′24″N 37°40′19″E) The Yauza Valleys, zoned specially-protected natural territories, are managed by city authorities as public parks.

Past Sokolniki, the Yauza enters a heavily-industrialized area; below Glebovsky Bridge ( 55°48′22″N 37°42′7″E) it flows in a man-made channel shaped by granite embankments, with heavy traffic on both sides.

The Yauza collects waters from many tributaries, most of them confined to underground sewers. The few that remain on the surface, at least partially, are (north to south):^[12]

Western (right bank) tributaries	Eastern (left bank) tributaries
Sukromka ( 55°53′49″N 37°41′15″E) Chermyanka (12 km,  55°51′41″N 37°38′6″E) Likhoborka (16 km,  55°50′38″N 37°37′45″E) Kamenka (7 km,  55°50′26″N 37°37′56″E) Putyaev and Oleny brooks in Sokolniki Park	Ichka (12 km,  55°53′14″N 37°40′55″E) Budayka (4.4 km,  55°49′34″N 37°40′3″E) Khapilovka (all confined to sewer,  55°47′10″N 37°41′56″E) with tributaries Serebryanka (12 km) and Sosenka (9 km) running naturally through Izmailovo Park. This is the largest subsystem of the Yausa basin, with its own drainage basin of 75 square kilometers.

Lefortovsky Bridge, one of the oldest in Moscow, was built in 1777.^[13]

The flow of the Yauza is regulated (particularly in winter)^[14] and reinforced with water from the Volga River that reaches the city through the Moscow Canal.^[14] 80 million cubic meters^[15] of Volga water is sourced each year from the Khimki Reservoir in northwest Moscow and fed through underground pipes and an open channel to Golovinsky Ponds and the Likhoborka River (a tributary of the Yauza).^[1] The water level in the lower Yauza is regulated by the Pererva Dam ( 55°40′21″N 37°42′51″E) on the Moskva River, and by the locks ( 55°45′23″N 37°40′16″E) on the Yauza itself east of Kursky Rail Terminal. Raised water levels in the downtown portion of the Yauza basin led to long-term flooding and death of trees deep inside Losiny Ostrov.^[16]

Within the city of Moscow the Yauza is spanned by 21 road bridges, five railroad bridges, one dedicated tram bridge, two Moscow Metro bridges, numerous pedestrian bridges and the historical Rostokino Aqueduct. Spring floods due to low clearance under old bridges were common, with four in the 1950s alone (1951, 1952, 1955 and 1957); they were practically eliminated when these bridges were rebuilt to modern standards.^[17] The most recent flash flood on the Yauza occurred August 14, 2003, following a record-setting rainfall.^[18] The Yauza and its valleys are not particularly prone to the landslides and erosion common in the western and southern districts of Moscow. There were two minor landslides on the Yauza in 2008, compared with 40 on the Chertanovka River and 33 on the Gorodnya River.^[19]

There is no commercial or recreational shipping, although the river is accessible to small motor boats as far as Preobrazhenskaya Square^[1] ( 55°47′42″N 37°42′14″E).