Map of the canals (nahrs) along the Blind Tigris (modern Shatt al-Arab) in southern Iraq in around 900 AD. The canals are as follows:
1. Nahr Abu al-Asad
2. Nahr al-Marah
3. Nahr al-Dayr	
4. Nahr Bithq Shirin
5. Nahr Ma'qil
6. Nahr al-Ubulla
7. Nahr Abu al-Khasib
8. Nahr al-Amir
9. Nahr al-Qandil
Not depicted: the Nahr al-Yahudi, between the Nahr al-Ubulla and the Nahr Abu al-Khasib.
Background map is from Le Strange, Lands, Map II. The information on the canals comes from Le Strange, Ibn Serapion, pp. 297, 299-300, 303-307.
References:

Le Strange, Guy. "Description of Mesopotamia and Baghdad, written about the year 900 A.D. by Ibn Serapion." The Journal of the Royal Asiatic Society of Great Britain and Ireland for 1895. London: Royal Asiatic Society, 1895.
Le Strange, Guy. The Lands of the Eastern Caliphate: Mesopotamia, Persia, and Central Asia, from the Moslem conquest to the time of Timur. Cambridge: Cambridge University Press, 1905.
Own work
Ro4444