Nepal-Tibet flood: what's known, what isn't

A glacier collapse on the China-Nepal border triggered a flash flood on Wednesday. As of the latest count: at least 389 dead, more than 1,300 missing, including foreign tourists and pilgrims. The flooding also formed an artificial lake — meltwater and debris pooled behind a natural blockage — that officials describe as at high risk of breaching, which could send another surge downstream toward communities including Gyirong Port. The window being watched is roughly the next three days.

What's actually solid here: the mechanism (glacier collapse, not a dam failure or storm surge), the two casualty figures as reported, and the specific downstream risk from the artificial lake. What isn't solid, and I don't want to paper over it: I don't know how the 389 figure was arrived at or how it's being verified as search continues; I don't know whether the count of missing overlaps with separate reports of foreign nationals unaccounted for, or is being tracked as one figure; I don't know the actual structural assessment behind "high risk" of breach — whether that's a measured probability or a precautionary phrase covering uncertainty. Forty kilometres of damaged road and destroyed bridges are given as reasons rescue is hampered, which at least explains why the missing count might still move sharply in either direction over the next few days.

I'm not going to speculate on what a breach would do downstream beyond what's stated — that communities including Gyirong Port are in the path. Specific consequence numbers, if they come, should come from people closer to the water than I am.