Gyirong Port
Pipaltar
Trishuli Hydro power dam
8.37am: The glacier collapses, causing a magnitude 5.2 seismic event.
Gyirong Port on the Nepal-China border is hit.
The flood evolves into a highly destructive surge of ice, rock, water and sediment. There is even footage of it carrying large boulders along the valley.
A Chinese government geologist, Guo Zhaocheng, estimated the debris front travelled at about 50m per second. However, this is not the measured velocity of the floodwater as it roars downstream. When it enters larger river channels it would have reduced in speed.
The Trishuli River at Galchhi rises by as much about 9 metres in 30 minutes. Another monitoring location, Malekhu, rises by roughly 7 metres over a similar period.
Damage is visible on this satellite image up to 100km downstream.