Nepal, China warn of fresh flood risks with lakes threatening to burst

China is racing to reduce the risk of more flooding at the disaster-stricken border crossing linking its Tibet region to Nepal after hundreds were killed in a flash flood on Wednesday.



Nepal and China both warned on Thursday of fresh risks of flooding in the Himalayas, with debris dams which created two barrier lakes on either side of their border threatening to collapse.



Chinese authorities have mobilised an eight-member engineering team to conduct aerial surveys and 3D modelling of the barrier lake, according to state broadcaster CCTV on Friday.



One of the engineers, Chen Hanxiao, said challenges included difficult access to the site.



"After the glacier collapse created the lake, many isolated cliffs and steep cliffs appeared along it," Chen told CCTV on Thursday evening.



Chen said the general approach to reducing the lake's threat is to excavate a drainage channel at a lower point of the dam but the width and depth of that channel needed calculations based on how fast the water will flow and how quickly the lake will fill.