New findings from international scientists don show say di Bhotekoshi flood wey sweep enter Bhotekoshi River for Rasuwa, Nepal, after e start from Tibet, move at average speed of about 188 kilometres per hour. Di World Weather Attribution, WWA, one international organisation wey dey study extreme weather events, release di new findings about di speed of di flood.
Earlier, Nepalese flood experts bin describe di Bhotekoshi flood as di fastest flood recorded for di country so far. On August 27, one day after di disaster, flood expert Dinkar Kayastha estimate say di flood fit don travel at speeds up to 55 kilometres per hour. He talk say e fit possibly be di fastest flood ever recorded for Nepal. But di WWA study estimate say di flood travel at more than twice dat speed.
According to WWA, on August 26, one massive section of rock wey dey at altitude of more than 5,150 metres for Langtang Lirung Himal for Rasuwa break away and collapse. A portion of di glacier wey dey above am also come down wit di rock mass. Di huge quantity of rock and ice wey cascade downhill trigger one rapidly moving mixture of water, mud, boulders and ice. By di time di debris reach Lhende Khola, e don transform into one powerful flood.
Di report tok say di flood travel approximately 22 kilometres from Langtang region to Rasuwagadhi border area in just seven minutes. Scientists describe di speed as comparable to dat of a conventional passenger train. Dem tok say such flow never dey observed before for Nepal rivers. At dis speed, di mixture of rock, ice, mud and water surge into di Bhotekoshi River before e cause extensive destruction downstream.
More than 20 scientists from different countries contribute to di study. Di report prepare wit collaboration of researchers and experts including Ben Clarke, Miriam Zachariah, Bethan Davies, Rejine Hacquard and Walter Immerzeel.
Di flow, wey carry ice, rocks and massive quantities of debris, travel through di Bhotekoshi and eventually reach di Trishuli River. For di process, 15 local administrative units across five districts, including Rasuwa, Nuwakot and Dhading, suffer extensive loss of life, property and infrastructure. More than 1,400 deaths don confirm so far for di disaster, while around 6,000 people dey reported missing. Infrastructure worth billions of rupees also destroy by di flooding. Di powerful flow cause extensive erosion and destruction for several areas, including Timure, Syafrubesi, Mailung, Betravati, Sole, Tupche, Bhainse, Trishuli Dhunge and Devighat.
According to di scientists study, di floodwaters reach Devghat for Chitwan, approximately 200 kilometres away, in less than seven hours. For Devghat, di river discharge rise to around 5,850 cubic metres per second. Scientists estimate say additional volume of approximately 20 million cubic metres of water enter di river in less than four hours. In addition, around 30.5 million cubic metres of mud, rocks and other debris carry downstream and deposit across various areas. Di enormous volume of water and debris significantly intensify di scale of destruction for areas surrounding di Bhotekoshi and Trishuli rivers.
