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The history of dutch floodings - Coggle Diagram
The history of dutch floodings
While the South-west of the Netherland was being flooded, the people behind the Afsluitdijk
slept safe and sound.
They already had the technology, they now have the willpower, all that was needed was
a plan.
But some of you might be wondering why they called it the Delta works.
Well, the region through which most of the flood came in is called the ‘delta region’
because 3 different rivers end in this region: Meuse, Schelde, and Rhyne.
So the Delta Works is named after the Delta Committee and the Delta committee is named
after the Delta Region…
So, we’ve come full delta.
The committee spent over 2 years gathering data and setting up the Delta Plan.
Over those 2 years they presented 5 points on how The Netherlands should improve its
flood defences.
In total, the costs were estimated to be about 2 billion Guilders, which is about 6.5 billion
Euro in today’s money.
That doesn’t sound like a lot today.
Afterall, humanity possesses far better technology, far more resources, and far more abundant
manpower.
But 2 billion guilders in 1955, was a tremendous amount of resources to devote on a single
project.
In fact, this was about 13% of the entire Dutch economy at the time.
To put the scale into perspective, if the Netherlands would try to spend a similar amount
of their GDP on a project today, it would be about 120 billion Euro.
That’s enough money for the Netherlands to fund 3 missions to Mars all on their own,
including all the Research, Development, and infrastructure… at least with Mars the Dutch
won’t need to worry about flooding.
Now the analyses were completed, the plan had been laid out, and the costs had been
calculated.
It was time for parliament to vote on the Delta Works.
With a landslide victory for the Delta-law in parliament, it passed through the senate
in 1958, and a day later was signed into law with the signature of Queen Juliana.
The work could now begin.
But WHERE to begin?
You can’t do everything all at once, the Netherlands simply lacked the resources to
do so at the time.
And so the decision on where to start came when the committee published their 2nd suggestion:
they concluded that the lowest point of the Netherlands, near Rotterdam, was also the
most likely to flood and the most deadly with 3 million people living behind that dike in
cities like Rotterdam, Delft, and the Hague.
In fact during the flood, a hole did get into the dike.
Whenever people tried to throw bags of sand in the dike to plug it, the water would immediately
drag it away again.
Realising the imminent danger they were facing, the local mayor convinced a local merchant
captain to use his 18 meter ship to plug the 15 meter wide hole.
Because of the bad weather the ship might get blown away again.
So he rammed the ship into the dike, giving rescue workers just enough time to fill the
hole with sandbags.
Without their efforts, millions of people might have become homeless, rather than ‘just’
70.000 people.
And you can visit the monument they put there in honor of this captain and the rescue workers.
And so when the Delta Committee published their findings on just how vulnerable this
area was, the local governments immediately funded the flood barrier which the committee
had suggested, without waiting for the national government to approve funding.
They built it right here, at the Algerabridge.
The flood barriers would be hoisted above the river to allow ships to pass underneath,
but can be lowered into the river in case of a flood.
Next came the largest part of the project.
You see, Zeeland was basically a collection of islands, resulting in around 700km of shoreline
which needed to be protected with 700km of dikes.
And so the key priority for the Delta Committee was to find a way to shorten these 700km to
just 80km.
They decided to do so by connecting the various islands to each other with dams, this meant
fewer weak spots, reduced maintenance cost, and increased quality of flood defences.
The plan called for the construction of 4 dams where the water from the river could
still flow into the North Sea, but the North Sea wouldn’t be able to flow into the rivers.
As well as several smaller dams further upstream which were needed to divert the flow of the
water in such a way so the water flows into the sea, instead of flooding the area behind
the major dams.
But as you may have noticed, the most southern inlet would not be dammed off.
This was because this waterway led to the port of Antwerp.
So the Dutch decided that damming one of the largest ports in Europe probably wasn’t
going to make them very popular so they kept it as is… damn belgians always messing up
infrastructure.
But this wasn’t the only accommodation made for the port of Antwerp.
You see, ships travelled between Amsterdam, Rotterdam, and Antwerp.
But this plan would make those waterways nearly inaccessible.
So to maintain the level of trade, the Dutch decided to dig some extra canals to let the
ships continue their business unhindered.
And so the Dutch began building various dams simultaneously, starting with the smallest
ones.
The Delta Committee acknowledged that no plan like this had ever been attempted.
They therefore advised to start with the smaller dams first in case of unforeseen consequences
arising halfway through the building process.
While each dam was a little different, the dams did fall within 3 types of dams.
The first type was the tried and tested method of using a gondola.
This was the same method they used when building the Afsluitdijk I mentioned earlier: they
would span a cable across the water, attach a large claw and used that to drop rocks into
the water until they reached all the way to the surface.
Then they would pump sand onto the rocks until it was filled up completely.
But this technique didn’t work in places with a strong current as the boulders wouldn't
stay in place.
So they developed a technique where they would place hollow concrete blocks into the water,
be kept in place with a temporary wooden construction, and filled up with sand.
Then they kept placing them next to each other until they had a dam.
To keep them all in place they poured sand and small stones on top the concrete blocks
until they had a proper dam.
This was called the ‘phoenix caisson method’.
Okay that sounds badass!
Engineers are MUCH better at naming things than historians are.
After completing a few of those dams they had effectively turned one of the Deltas into
a freshwater lake.
This had the effect that the flora and fauna, which was used to living in an environment
with both fresh and saltwater, was dying out.
And the goal was to completely dam off this area and the construction was nearing completion
of this goal.
But by the 70s people started caring a lot more about the environment.
And so local fisherfolk and environmentalists started protesting against this loss of flora
and fauna…
This reached all the way to parliament when the radically-progressive Christian Party,
made up mostly of young people, threatened to leave the ruling coalition if the government
wouldn’t find a solution to this environmental problem.
So the government decided throw a BUNCH of money at some engineers and scientists to
figure out a solution that protects both the people and the nature.
So a bunch of radically-progressive Christian BABY BOOMERS helped SAVE the environment…
wh…
I…
Okay Boomers, good job!
I wish 20s boomers were more like the 70s boomers…
The new plan took into account that most of the dam had already been constructed.
So they decided to keep the dam in place and focus on the unfinished parts.
Here they would put a storm barrier which could be lowered during a bad storm and kept
open the rest of the time.
This way, fresh and salt water mixture wouldn’t disappear and local wildlife would be preserved.
But how do you make the longest surge barrier in history?
Well, the plan was to CONSTRUCT ADDITIONAL PYLONS!!!
They create 65 giant concrete pylons upon which the engineers could place the actual
surge barrier.
These pylons were big, took 1.5 years to make, and had to be made on site.
So they used one of the three artificial islands which were already constructed for the original
dam and converted part of it into a drydock where they could build the pylons.
When the pylons were ready, a large trench was created on the riverbed.
Mats were placed on either side of the trench to prevent the soil from flowing into the
trench.
Then the sand underneath the Trench was vibrated to pack the sand together.
Now that the riverbed was sturdy enough for the pylons, they were picked up one by one
and delicately placed on the riverbed.
Each of the pylons was hollow, so to keep them in place they were filled up with sand,
while on the riverbed they were covered by stones.
Now that the pylons were locked in place, the engineers attached the barriers between
the pylons that will actually stop the waves.
With these dams and flood barriers finished, it would be nearly impossible for a flood
to hit this region of The Netherlands ever again… but there was still one section left.
While the delta region was secure, the city of Rotterdam wasn’t secure.
While the first delta work was created in the city, it needed 2 more just to be safe.
They built a flood barrier atop a river, which was very similar to the first delta work.
But the 2nd flood defence was a large system of dams along the river leading into Rotterdam
and the Port of Rotterdam.
This system required about 50 km of dams and demolishing part of the city with historical
buildings 400-year-old.
This was deemed too costly.
So this time, they let companies compete for
the best design that was relatively cheap, wouldn’t block passage to the Port of Rotterdam,
but would keep the people safe.
And the choice fell on a unique design: This storm barrier is one of the largest moving
objects ever created by humanity.
It had to be built piecemeal and assembled on site.
Due to the size of the individual pieces, the company had to hire several specialist
contractors to get the massive parts they needed.
There would be two barriers, one for each side of the river.
They were designed to rotate, so that when there was a flood risk, they would slide the
two barriers onto the river where they would meet in the middle.
Once in position, barriers would be filled with water so they slightly sink into the
river and can then withstand the oncoming storm.
And so… finally, in 1997, the last of the Deltaworks were finished.
And humanity had shown that it wasn’t so powerless after all.
The construction of all the projects combined lasted from 1954 to 1997 and not a single
one has ever failed since being put into work.
While a storm like the one in 1953 hasn’t hit the Netherlands since, there have been
several moments where the Deltaworks were being closed down to protect against oncoming
storms.
The Deltaworks were basically designed to last ‘forever’, in the minds of those
who made it.
It should literally last centuries with little maintenance, based on the weather patterns
of the 20th century…
But recent reports showed that as sea levels rise and the climate changes, the deltaworks
might not be able to stand against the tides of the future.
In a worst-case scenario, the sea levels will rise by up to 4 meters requiring a complete
overhaul of the deltaworks and the Dutch flood defences as a whole.
But don’t worry, I’ll make a video about that in a few decades if it does happen.
But for now, the Deltaworks has kept the Netherlands safe and will continue to do so for decades
to come.
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If you have any questions: I will try to answer all serious questions in the comments.
If you want to learn about the Afsluitdijk or how the Dutch dug up their own country
then click on the videos on screen now.
This was Avery from History Scope, thank you for watching.