The Sentinel-2 satellite finally captured a cloud free coverage of the 2018 Laos Dam Collapse site. Over a distance of more than 50km, everything near the river has been washed away, trees being stripped bare from the river banks.

Comparing it to the river pre-disaster shows how much energy was in the water: https://gfycat.com/LeadingAbsoluteConure

The map below shows what happened, one of the secondary dams overflowed, causing the reservoir to drain into another river.

source: http://www.gdacs.org/Public/download.aspx?type=DC&id=28