Rescuers warn new barrier lake may trigger second Nepal‑Tibet flood

A landslide that struck the remote region along the Nepal‑Tibet border last week has created a new high‑altitude lake, prompting authorities and scientists to warn of a potential secondary flood. The slide, triggered by heavy monsoon rains, dammed a tributary of the Arun River and caused water to accumulate behind the natural barrier. Satellite imagery confirmed that the lake, now spanning roughly 250 meters in length, is rising at an estimated rate of 0.8 meters per day, heightening concerns that the unstable moraine could fail and unleash a downstream surge.

Geologist Laura Bicker, who has been monitoring the site for the International Centre for Integrated Mountain Development, explained that the lake’s rapid expansion and the loose composition of the landslide debris increase the likelihood of a breach. She noted that similar glacial‑lake outburst floods in the Himalayas have caused extensive damage to villages and infrastructure. Nepal’s Ministry of Home Affairs has deployed a joint task force of engineers and military personnel to assess the dam’s integrity, install early‑warning sensors, and prepare evacuation routes for downstream communities. Continuous observation will determine whether controlled drainage or reinforcement measures are required to mitigate the flood risk.