Rivers, streams, and drainage features

Vltava

Vltava (Moldau), the longest river in the Czech Republic at 430.2 km, flows from Šumava to join the Elbe at Mělník; 28,090 km² basin, Vltava Cascade dams, historic floods of 1784 and 2002, and Smetana's 1874 symphonic poem.

Volga - Ural

Volga - Ural, FEOW freshwater ecoregion 410 (also Volga-Ural ecoregion), spans the Volga, Ural, and Emba drainages in Russia and Kazakhstan, draining to the Caspian Sea; temperate floodplain rivers with key sturgeon spawning grounds.

Volga (Волга)

Volga (Волга), Europe's largest river: 3,660 km from the Valdai Hills to the Caspian Sea, basin 1,380,000 km² covering a third of European Russia, regulated by eight reservoirs, with major pollution and 2025 low-water problems.

Volga Delta

Volga Delta: Europe's largest river delta, where the Volga (80% of Caspian freshwater inflow) splits into over 1000 waterways in Astrakhan Oblast; a low-gradient ramp delta shaped by rapid Caspian sea-level swings.

Volta

Volta: West African river system, 1,850 km long, draining a 400,000 km2 basin shared by Benin, Burkina Faso, Côte d'Ivoire, Ghana, Mali, and Togo; dammed at Akosombo in 1963-1964, creating Lake Volta and a major fishery.

Voyageurs

Voyageurs (voyageurs, engagés) were contracted French-Canadian canoe men of the North American fur trade, paddling 14-16 hours daily over 5,000 km routes for the North West Company from the 1690s to the 1850s.

Vritra (वृत्र)

Vritra (वृत्र), also Ahi, is the serpent or dragon of the Rig Veda who blocks the world's waters and is slain by Indra with the vajra made by Tvaṣṭar, chiefly in hymn 1.32; cognate with Avestan Vərəθraγna and read variously as cloud, drought, or winter demon.

Vyatka

Vyatka (Вятка; Udmurt Vatka, Tatar Nokrat) is a 1,314 km river in Russia, the largest right tributary of the Kama, flowing through Udmurtia, Kirov Oblast, and Tatarstan into the Kama 17 km below Mamadysh.

Vychegda

The Vychegda (Вычегда, Komi: Ezhva) is a river in northern European Russia and the largest right tributary of the Northern Dvina, flowing 1,130 km west.

Wabash

The Wabash River is a 764 km tributary of the Ohio River rising in western Ohio and crossing Indiana, whose lower two-thirds is the longest undammed river reach east of the Mississippi.

Wadi mouth

Wadi mouth: the lower terminus of a wadi where it widens into a floodplain, depression, or waterbody (code WADM). Ephemeral flash-flood sedimentation, fan deltas, estuarine facies, and flood hazards at arid coasts.

Wainganga

Wainganga River, also Vriddha-Ganga, a major Godavari tributary rising in Seoni district, Madhya Pradesh, flowing about 580-642 km through Maharashtra to join the Wardha and form the Pranahita.

Waitaki River

Waitaki River: South Island New Zealand river, about 68 miles long, catchment second only to the Clutha; heavily developed for hydroelectricity from the 1928 Waitaki Dam onward, birthplace of NZ social security.

Washita

Washita River, a 580-plus-mile Red River tributary rising in the Texas Panhandle and entering Lake Texoma, Oklahoma; site of the 1868 Battle of the Washita, the 1934 Hammon Flood, and 1,140 USDA flood control dams.

Watershed management

Watershed management organizes land, water, and resource use within a drainage basin, evolving into integrated, participatory, adaptive management using remote sensing, GIS, and modeling; effects include runoff cuts up to 25% and recharge gains of 40–70%.

Wei

Wei (渭河, Wei Shui), largest tributary of the Yellow River, 818 km, rising in Weiyuan County, Gansu, crossing the Guanzhong Plain past Xi'an to join the Yellow River at Tongguan; heavily irrigated since 246 BC, water-scarce, with declining runoff and falling sediment load.

West Florida Gulf

West Florida Gulf, FEOW freshwater ecoregion 154, a temperate coastal rivers ecoregion in southern Alabama and the western Florida Panhandle defined by the Perdido, Escambia, Blackwater, Yellow, and Choctawhatchee drainages, with endemic darters and long-leaf pine forests.

West Texas Gulf

West Texas Gulf (FEOW ecoregion 139) is a freshwater ecoregion of southern Texas defined by the San Antonio and Nueces river watersheds, with karst Edwards Plateau headwaters, few endemic fishes, and Gulf of Mexico drainages.

Western Anatolia

Western Anatolia is a freshwater ecoregion (FEOW 429) spanning the Aegean coast of Anatolian Turkey between the Sea of Marmara and the Mediterranean, known for endemic fishes.

Western Bug

Western Bug (Західний Буг, Polish Bug): 772 km river rising in western Ukraine, flowing to the Narew and Vistula basin; 363 km forms the Poland-Ukraine-Belarus border, distinct from the Southern Bug.

Western Caspian Drainages

Western Caspian Drainages: a Freshwater Ecoregions of the World (FEOW) ecoregion on the western Caspian coast, covering Terek, Sulak, and nearby rivers draining into the endorheic Caspian Sea.

Western Hudson Bay

Western Hudson Bay is FEOW freshwater ecoregion 111, Polar freshwaters, covering watersheds in northern Manitoba, Saskatchewan, the NWT, and Nunavut draining via the Thelon, Seal, and Thlewiaza rivers into Hudson Bay.

Western Madagascar

Western Madagascar (FEOW ecoregion 579) is a xeric freshwater ecoregion covering the Manambolo, Tsiribihina, Mangoky, and Onilahy river basins, defined by under 1400 mm annual rain, seasonal drying, karst tsingy habitats, and poorly surveyed, highly endemic fish faunas.

Western Orange

Western Orange (FEOW ecoregion 572) is a freshwater ecoregion of southern Namibia and northern South Africa covering the lower Orange River below the Vaal confluence, with Augrabies Falls as its only natural fish barrier and a largely xeric, impoverished fauna.

Western Taiwan

Western Taiwan (FEOW ecoregion 757) is a freshwater ecoregion of Taiwan's west-draining basins, including Penghu; main rivers Tamshui, Zhuoshui, Kaoping; nearly a quarter of its fish species are endemic.

White Nile

The White Nile is the longer Nile tributary, rising at Lake Victoria and flowing through the Sudd wetlands to join the Blue Nile at Khartoum, contributing about 28% of Nile discharge with steady year-round flow.

White Volta

White Volta (Nakanbé in Burkina Faso), a 660 km river rising in Burkina Faso and flowing through northern Ghana to the Volta Reservoir; basin 92,880–107,417 km², September flood peak, Bagre Dam spillage flooding, major tributaries Red Volta, Kulpawn, Nasia.

Wolf River (Tennessee)

Wolf River (Tennessee): ~100-mile Mississippi River tributary rising at Baker's Pond, Mississippi, flowing through Fayette and Shelby counties to Memphis; lower 22 miles channelized in 1964; wetlands recharge the Memphis Sand Aquifer; distinct from Mississippi's Gulf Coast Wolf River.

Wu

Wu (乌江, Wujiang, Wu River), largest right-bank tributary of the upper Yangtze: 1,037 km, 2,124 m drop, karst basin of 87,920 km2, an 11-dam hydropower cascade totaling 8,665 MW in Guizhou.