The Ob River: Siberia's Great North-Flowing Artery

The Ob River is western Siberia's principal waterway—3,650 km (2,268 mi) long, draining 2.99M km² into the Arctic's Kara Sea.

Formation & Course

• Source: Confluence of Biya (Lake Teletskoye) and Katun (Altai glaciers) at Biysk (52.5°N, 85.2°E)
• Upper Ob: Narrow, forested, swift — Biysk to Novosibirsk
• Novosibirsk: Largest city (1.6M); Trans-Siberian crossing; massive hydro dam (Novosibirsk Reservoir, "Ob Sea")
• Middle Ob: Broadens into West Siberian Plain — meandering, floodplains, wetlands (Vasyugan Swamp — world's largest)
• Lower Ob: Splits into distributaries; forms Gulf of Ob (1,000 km long estuary)
• Mouth: Kara Sea at 66.5°N, 66.5°E

Major Tributaries

Economic Significance

• Navigation: 3,500 km navigable (ice-free Jun–Oct); NSR connection
• Hydropower: Novosibirsk (400 MW), planned others
• Oil & Gas: West Siberian Basin = Russia's largest hydrocarbon province; Samotlor, Fyodorov, Priobskoye fields
• Fisheries: Sturgeon (beluga, sterlet), nelma, muksun, peled — declining
• Water supply: Novosibirsk, Omsk, Tyumen, Surgut, Nefteyugansk

Environmental Pressures

• Industrial pollution (metals, phenols, petroleum)
• Hydrological alteration (dams, water withdrawal)
• Permafrost thaw → bank erosion, carbon release
• Sturgeon poaching (caviar)

The Ob-Irtysh system = 7,900 km combined — world's 7th longest. Siberia's circulatory system.