5 May 2020
The Sardoba dam failure: flood routing
After my blog post yesterday about the 1 May 2020 Sardoba dam failure in Uzbekistan, several people have asked about the flood routing between the breach and the large inundated area that I showed in my post. The Planet Labs imagery shows this clearly, and it is quite an interesting story.
We can start with the area around the dam – the Planet Labs image below shows the breach in the lower left and the now partially drained reservoir:-
Scouring immediately downstream of the breach is clear, and there is a distinct channel that follows the wall of the dam, initially towards the north and then towards the east. This is shown in more detail below:-
There is also evidence from the images that the water inundated a much larger area in the vicinity of the dam, and on 3 May 2020 there was still some evidence of minor flooding. From there, the water spread across a broad area rather then being channelised, as the image below illustrates:-
In this image there is extensive damage to the fields (and presumably to the villages) across a wide area. Towards the northeast there are areas that remain submerged, and at the top of the image the flow has channelised once more as the water moved into the extensively ponded area that I showed yesterday. The imagery collected on 4 May 2020 shows that this area remains deeply flooded.
Thus the Planet Labs satellite imagery demonstrates that the Sardoba dam failure has caused flood damage over a broad area of this part of Uzbekistan.
On reflection 1: EGU General Assembly Day 2
Today is day 2 of the EGU2020 virtual meeting. This is the list of the landslide sessions on Day 2 – it is a busy landslide day:-
NH3.5 Debris flows: advances on mechanics, monitoring, modelling and risk management
Displays Chat Tue, 05 May, 14:00–18:00
NH3.1 Large slope instabilities: characterisation, dating, triggering, monitoring and modelling
On reflection 2: recent landslides
Uganda and Kenya continue to be battered by heavy rain and resultant floods and landslides, whilst a landslide in New York State has left houses teetering on the edge of disaster. In China, the early part of the rainy season is just getting under way.
Planet Team (2020). Planet Application Program Interface: In Space for Life on Earth. San Francisco, CA. https://www.planet.com/