siang river
Siang river in Arunachal Pradesh--Representational imageWikimedia Commons

The East Siang district in Arunachal Pradesh (AR) is now under a flood alert and authorities there are asking people to not go near Siang. This, after an artificial lake was formed as a result of a landslide where a cliff fell on to a section of the Yarlung Tsangpo river in China on Wednesday.

The water level on the Siang river in AR is reported to have reduced because of the lake's formation and as a result, could lead to large-scale floods if the temporary dam that the landslide created collapses, reports the HindustanTimes.

Yarlung Tsangpo river is known as the Siang after it enters India at Arunachal Pradesh from the Tibetan region. It is the same river that is called the Brahmaputra once it reaches Assam, explains the report.

"We got a report from the Central Water Commission (CWC) about the landslide in Tibet. The water level in Siang river has gone down by around 2 metres at Tuting in Arunachal Pradesh," said Duly Kamduk, deputy commissioner of Upper Siang district.

The landslide is reported to have happened near a village in Menling County. This led the water in the newly-formed lake to rise to 131 feet by Thursday, 18 October, Chinese authorities, have reported.

East Siang authorities have issued warnings to people from wandering into the Siang and its surrounding areas where people tend to go to collect driftwood, fish, or just swim, notes the report. A sudden flash flood in its downstream can be expected if the natural dam ruptures and releases all of the accumulated water.

"And also people living in low lying areas (both the right and left bank of Siang River) viz Jarku, Paglek, SS Mission, Jarkong, Banskota, Berung, Jampani, Sigar, Ralling, Borguli, Seram, Kongkul, Namsing, Mer, Gadum, etc to remain alert but without panic for any eventuality that may happen due to above reasons," it said in a statement.

"Further, it is directed that driftwood such logs, trees, bamboos clamps, and any uprooted vegetative materials brought by the river from upstream and parked along the banks both the banks of the Siang River shall not be as to serve as a Natural Flood Control Mechanism," it added.

The warning issued also noted that anyone violating said orders are liable to be charged under section 188 of IPC and other relevant provisions of the law, notes the report.

From the Chinese side, the sudden appearance of the lake has prompted officials to evacuate about 6,000 people in Tibet, reports the Associated Press from Beijing, notes the report. China has also reportedly informed India of this development.