Adhwara is a group of one and a half dozen small and big rivers flowing in the Mithila region. According to legend, it is mentioned in Vedas and Puranas. It is also known as Chhoti Ganga of the region.[2] The rivers of the Adhwara group remain in spate during heavy rains in the Mithila region or in the Terai region of Nepal. During this period, it causes several destruction in the region due to huge floods caused by over flow from these rivers. The major rivers or streams of the Adhwara group are Bigghi, Dhouns, Thumhani, Khiroi, Kokra, Bachharaja, Lakhandei, Marha, Hardi, Raato, Jhim, Lalbakaiya and Jamuni, etc.[3][4][5][6][7]
The Adhwara group is one of the eight river basins in the Flood Management Information System (FMIS) focus area of Bihar. About 70% of discharge of the group passes through the Khiroi river and rest of 30% discharge passes through the Dhouns river that meets at Akharharghat.[8]
