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Photo: ICEYE
After the flood is before the flood.
For better or for worse, the people of the small town of Richmond have gotten used to it.
Her home in the Australian state of New South Wales has recently been hit by severe flooding again and again: in spring 2021 and 2022 - and now again.
Heavy rain has once again caused the Hawkesbury River, which encircles the Sydney metropolitan area, to burst its banks.
And once again the – actually flood-proof – bridge that connects Richmond with North Richmond on the other side of the river is closed.
The Guardian quotes an annoyed resident as saying that the bridge has already been closed five times in two years.
This is also due to "mismanagement" at Warragamba Dam.
This stands on the Warragamba River, a tributary of the Hawkesbury River.
Australia has been debating for years whether the dam's crown should be raised by up to 17 metres.
Opponents argue, among other things, that parts of the UNESCO-designated Greater Blue Mountains World Heritage Area would then be flooded and that it could even lose its World Heritage status as a result.
Proponents argue with more flood security.
According to official figures, 515 million cubic meters of water from the overflowing dam ended up in the Hawkesbury River on Sunday alone.
In the days that followed, the rate fell, to around 380 million cubic meters on Monday, but it was still considerable.
To put this into perspective: In the Elbe in Magdeburg, the state capital of Saxony-Anhalt, around 34.6 million cubic meters of water flow per day.
Sunday's false-color image shown above shows the swollen Hawkesbury River as a black band.
Not far from Richmond, above center, a large area of low-lying agricultural land has been flooded, which is also dark.
To see the bridge to North Richmond you would have to zoom in very far into the shot.
Even at high magnification, it would only be recognizable as a thin, bright line.
On the other hand, the runways of the RAAF Base Richmond can be seen better.
The Australian Air Force has stationed its Lockheed C-130 Hercules transport aircraft here.
Australia's Defense Minister Richard Marles invited to a briefing at the airfield on Monday - because his boss, Prime Minister Anthony Albanese, had left for a trip to Ukraine despite the floods.
View through clouds
The satellite image was taken by a radar satellite from the Finnish company Iceye.
The technology used also makes it possible to take pictures through clouds or in the dark.
The company launched its first satellite into space on an Indian rocket in January 2018.
It now operates a fleet of more than a dozen examples.
Since autumn 2019, the images have been commercially available with a resolution of up to one meter.
The company advertises that overflights every 24 hours give it a particularly good view of changes on the earth's surface.
In this way, the height of the container stacks in ports could be measured or the question of where the ground was opened - for example during construction work - could be answered.
The comparative technique also provides another fascinating view of the tides around Richmond.
Where one could otherwise move with dry feet - in the illustration these are the white and gray areas - the water is now sloshing in many places, shown in blue.
The illustration compares the expansion of the waters before the flood with that on Sunday.
The differences are impressive.
And it won't be the last time that the people of the region have anything to do with water.
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