How Much Water Is in the Danube River? Flow and Volume

The Danube is Europe's second-longest river (2,850 km) and a critical water artery for 10 countries.

Flow Rate (Discharge)

• Average discharge: 6,500 m³/s (at mouth, into Black Sea).
• Range: 1,500 m³/s (winter low) → 15,000+ m³/s (spring flood).
• Peak recorded: ~16,000 m³/s (2006, 2013 floods).

Total Volume in Channel

• Instantaneous volume (water in river at any moment): ~180 billion m³ (0.18 km³).
• Calculated as average discharge × residence time (~7–8 days transit).

Annual Flux

• ~205 km³/yr delivered to Black Sea (6,500 m³/s × 31.5M s).
• Represents ~65% of total river input to Black Sea.

Key Context

• Drainage basin: 801,463 km² (19 countries).
• Major tributaries: Inn, Drava, Tisza, Sava, Prut.
• Hydropower: 59 dams (Iron Gates I & II largest).
• Navigation: 2,415 km navigable; Rhine–Main–Danube Canal links North Sea to Black Sea.

The Danube moves a cubic kilometer of water every ~1.7 days—sustaining ecosystems, agriculture, industry, and transport across Central and Eastern Europe.