Why does the White Nile provide a steady supply of water?

The White Nile provides a steady, regular supply of water throughout the year, even during periods when the main river's flow is at its lowest. This consistency is primarily due to two main sources that contribute water in roughly equal amounts:12

• East African Plateau: The river is fed by rainfall on the East African Plateau from the previous summer.1
• Sobat River: The drainage of southwestern Ethiopia through the Sobat River provides a significant contribution. While the Sobat's own flow varies due to Ethiopian summer rains, its input helps maintain the White Nile's volume.1

Additionally, the discharge of the Al-Jabal River—a major component of the White Nile system—is regulated by the vast swamps and lagoons of the Al-Sudd region, which helps stabilize the flow. Because of these factors, the White Nile accounts for more than 80 percent of the total volume of the main Nile during the low-water months of April and May.12