(lengths within the borders of the state; Units are in miles (kilometers)

Brahmaputra  435 (700)
Burhidihing    223 (360)
Danshiri (South)  219 (352)
Subansiri  198 (318)
Kopili  185 (297)
Dihang  163 (263)
Disang  142 (230)
Dikhou  124 (200)
Lohit  119 (192)
Puthimari  118 (190)
Kalang  106 (171)
Manas (Main)    95 (153)
Jinjiram   89 (143)
Dikrang   83 (134)
Kulsi   76 (122)
Janji   67 (108)
Aai   64 (103)
Nonoi   60 ( 97)
Gangadhar   62 ( 99)
Dhansiri (North)   58 ( 94)
Ronganadi   63 (102)
Krishnai   50 ( 81)
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Sources of the information: Adhunik Asomia Manchitra edited by Bijay Kumar Dutta, Student Stores, Guwahati, First edition, 1988