The Kameng river in Arunachal Pradesh recently witnessed a mass fish death due to a landslide triggered by a 3.4 magnitude earthquake near the border with China. This region is situated within Seismic Zone V, making it highly susceptible to earthquakes.
The earthquake’s epicentre was close to the river’s source, located at an elevation of approximately 6,300 metres above Mean Sea Level. The resulting landslide displaced several tonnes of rocks and soil into the water body, greatly diminishing the flow of the river.
Implications of High Turbidity and Low Dissolved Oxygen Levels
The mud and rock deposits from the landslide led to the river water turning blackish, indicating high turbidity. This had a direct impact on the dissolved oxygen levels in the water, significantly lowering them which consequently led to the fish deaths.
Naturally, low dissolved oxygen concentrations can occur due to seasonal changes, variations in river flow and both saline and thermal stratification of the water column. Such low levels can also hint at a higher demand for oxygen in the system.
Details about Kameng River
Kameng River originates from a glacial lake beneath the snow-covered Gori Chen mountain located on the India-Tibet border, specifically in Tawang district. Contrary to some notions, Kameng is not a transboundary river. Though it originates near the border, its entire course is situated within Indian territory.
The river flows through the Bhalukpong circle of West Kameng District, Arunachal Pradesh and Sonitpur District of Assam. As it reaches its lower courses, the river becomes braided and serves as one of the significant tributaries of the Brahmaputra River.
Natural Boundaries and Tributaries
The river converges with the Brahmaputra River at Tezpur, Assam, a little east of the Kolia Bhomora Setu bridge. Additionally, the Kameng River forms the natural boundary between the East Kameng District and West Kameng Districts. It also separates two sanctuaries, namely, Sessa and Eaglenest to its west and the Pakke tiger reserve to its east.
The Dafla Hills are situated east of the Kameng River while the Aka Hills are positioned towards its west. The Kameng River is associated with several tributaries including Tippi, Tenga, Bichom and Dirang Chu.
Historical Relevance of Kameng River
From the 13th until the early 16th century, the Kameng River served as the demarcation line between the Chutiya kingdom and the Kamata kingdom. It continued to have strategic importance in the 16th century as it became the border between the Ahom kingdom and Baro-Bhuyan rule, post the annexation of the Chutiya kingdom by the Ahoms and the collapse of the Kamata kingdom.
The Chutiya Kingdom had developed around Sadiya in present-day Assam and adjoining areas of Arunachal Pradesh. The Kamata kingdom emerged when Sandhya, a ruler of Kamarupanagara, relocated his capital west to Kamatapur after 1257 CE. Kamarupa corresponds to what is now the state of Assam.
Sukapha founded the Ahom kingdom, which ruled Assam for six centuries, in the 13th century. The term Baro-Bhuyans pertains to the confederacies of soldier-landowners in Assam and Bengal during the late middle ages and early modern period.