The Adda River is a river of South Sudan, a tributary of the Bahr al-Arab.

The river flows through the Western Bahr el Ghazal, South Sudan.

The average elevation is 499 metres (1,637 ft) above sea level.

[1] It joins the Umbelasha River opposite the town of Radom, Sudan, to form the Bahr al-Arab, which defines the border between South Sudan and Sudan.

[2]