Unified Deep Water System of European Russia

The Unified Deep Water System of European Russia () or UDWS () is a system of inland waterways in Russia linking the White Sea, the Baltic Sea, the Volga River, Moscow, the Caspian Sea and—via the Sea of Azov—the Black Sea. In 2010, UDWS carried 70 million tons of cargo and 12 million passengers, making up two-thirds of overall inland waterway traffic volume in Russia. There are 60 common-use ports and quays in the UDWS, including three international ports (two in Moscow and one in Dmitrov, Moscow Oblast), so Moscow is sometimes called "the port of the five seas".

The depth throughout the system was targeted at , allowing passage of not only river craft but many sea-going vessels including warships and even nuclear submarines. However, the depth is mostly guaranteed at only  and some sections are even shallower, such as Gorodets–Nizhny Novgorod at  and Kochetovsky Bagayevskaya at . There are plans to increase depth of these sections to 4 m.

The system includes these waterways:
Neva River
Lake Ladoga
Svir River
Lake Onega
Volga–Baltic Waterway — connects Lake Onega to the Volga River; built in the early 19th century as Mariinsk Canal System and rebuilt in 1956–1964
White Sea–Baltic Canal — connects Lake Onega to the White Sea; constructed in 1931–1933
Moscow Canal — connects Moscow to the Volga River; constructed in 1932–1937
Volga River
Kama River
Belaya River
Volga–Don Canal — connects the Volga River to the Don River; constructed in 1948–1952
Don River

Environmental impact
In 1999, the warty comb jelly colonized the Caspian Sea via the UDWS. The establishment of this population led to a 60% reduction in the number of sprat, which in turn led to a reduction in the population of sturgeon and seals.

In total, according to the unified federal/state agency CaspNIRKh (), about 60 alien species of plants and animals penetrated into the Caspian Sea in the 20th century, which has led to significant changes to ecosystems.

See also
Don–Volga-Portage
Eurasia Canal

References

Category:Water transport in Russia