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s5300

Wow.

70 deaths in these countries just from flooding seems like... a lot in the year 2021

Note: I am fully aware of the dangers/extreme power of fast moving water/flooding

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A few examples of such deaths:

- An older man was found dead in his flooded basement. Presumably he went to check the status but exact circumstances and cause of death are not clear yet. - Another older man tried to remove some branches from a clogged drain pipe. When he succeeded he got dragged along with the sudden surge of draining water and has not been found since.

- A twenty-something guy got the idea to go 'play around in the water with some kind of floaty toy'. He got dragged away.

- A fire brigade rescue boat got into trouble during a mission. The three elder people they had rescued went overboard and have been missing since. Two of the five firemen on the boat also went overboard but managed to secure themselves until they were rescued.

It's a tragedy. Flooding of this scale has not been seen here. People don't know the dangers. And culturally a house is quite important for most people (the saying is that we "are born with a brick in our stomach") so they often refuse to leave their house.

The last decade or so there have been improvements to give rivers more space, open up streams again that got covered up, make available basins that can be flooded to buffer water, increase/strengthen dikes and embankments, ... But what we've seen now was of a different order of magnitude: we've had locations that got like 100L+ of water in 24h whereas they would normally receive 800L in a whole year.

Yes, it's quite the horrific number, and I expect it to rise still ... here in Germany it's currently 59 confirmed, that number was lower a few hours ago - and apparently this doesn't even include bodies they know exist, but couldn't get to yet. And 1300 missing currently.

This village was essentially completely destroyed - this is the best visualization of this I've seen, from /r/europe: https://i.redd.it/9fdhwvte8fb71.jpg

We have apparently no statewide warning mechanism or even if we had, had the foresight to evacuate this region - now, there are calls for evacuation for other, not yet flooded, regions.

I have most of the info from this German article: https://www.zeit.de/gesellschaft/zeitgeschehen/2021-07/unwet...

I had a warning for 'extrem erbiebigem dauerregen', I think since sunday or monday in the Nina app. So something like extremely plentyful sustained rainfall. I think putting 1 and 1 together, you could expect some flooding to occour. But of course the details (where do we actually need to evacuate) are more complex. It seems for example my city, while inside the region wasn't hit nearly as hard as a few years back, which was already a once in a century flooding, but not so widespread.

This is a shocking picture; as if the whole town was built on top of an ancient river.

Yup. There's clearly a former oxbow there.

Europe was basically all deforested farmland at one point. As it industrialized the last places farming was economically viable were the most fertile land which is going to be the floodplain and the river's former oxbow and resulting swamp.

Then a developer probably comes along (say 1910 or 1920 or something) and builds on the easiest to build land, which is the already cleared land of the last farm to croak. Then 100yr later we get a record rainfall and the river takes it all back for a couple weeks.

And actually ancient, the specific village was first mentioned in 1074[1], and a nearby city was at least a settlement in 1000-500 BC[2].

So it's not like extreme floodings there are common, which makes it even worse.

[1]https://en.wikipedia.org/wiki/Heimerzheim

[2]https://en.wikipedia.org/wiki/Bad_Neuenahr-Ahrweiler#Antiqui...

Could they use GPS or another elevation measuring device to create a elevation and flood map?

To do what exactly? People aren't going to abandon their homes and build a new house somewhere else just because there is a flood risk. In the UK it's estimated 1 in 6 homes are at risk of flooding.

https://www.safesitefacilities.co.uk/knowledge-base/areas-mo...

Such a map could and should be used to inform the building of new houses and zones for houses in the long term. I am living just 100 km away from that area and the risk of flooding was one factor I considered when buying my current house. (Spoiler it is near the top of small hill with a slow rising slope)

Such maps exist (called "Hochwassergefahrenkarte" in Germany), but comparing the picture of Altenburg linked elsewhere in this topic and the map, the flooding has significantly exceeded even the "HQ extrem" (= extreme flooding, defined as a 200-year-or-rarer flood) level.

And officially designated flood plains with associated legal restrictions are usually based on a 100-year flood.

They almost certainly have this data already. I live in Dresden, a city in East Germany that also has its fair share of floods from the Elbe river [1]. The city has an interactive map where you can display flood maps for various levels. It actually has an English version as well, so you guys can try it if you want: Go to [2], switch to English in the upper right corner if it does not autoselect English for you, enter "flood" in the search box and select one of the overlays like "at 900 cm at Dresden Gauge".

[1] The last "Jahrhunderthochwasser", floods of the century, were in 2002, 2006 and 2013, so yeah, that label does not stand up to scrutiny anymore.

[2] https://stadtplan.dresden.de/

It exists, like on the geoportal [0] of the Walloon Region (south of Belgium), but this time it's really unprecedented. I'm working for the Belgian railways and it's apocalyptic.

[0] https://geoportail.wallonie.be/catalogue/9c55d236-8d98-4964-...

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