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  • The Delta Works are one of the Seven Modern Wonders, They are the largest system of flood

  • defences in the world, and they are currently being used as the template for many countries

  • on how they should defend themselves against rising sea levels.

  • But how could such a small country construct one of the most advanced flood defences?

  • To answer this, let's take a look at its history.

  • The Dutch had been building dams and dike and other flood defences for millenia.

  • In fact, the first settlers of the Netherlands built their settlements on hills because of

  • the frequent floods.

  • They are called 'the low countries' afterall.

  • And the first dams, dikes, and dunes created by the Dutch were built in the 8th century.

  • But as the Netherlands grew richer and more populous, the flood defences wer improved.

  • In the 1930's the Netherlands constructed the longest dam in the world, the Aflsuitdijk,

  • to protect the central region of the Netherlands against floods.

  • You can watch my video on that after this one by clicking on the link at the end of

  • this video.

  • Now that that project was completed, the Dutch government started looking into plans to dam

  • off the south-western part of their country as well, right here in Zeeland.

  • Which is the Zeeland that makes New Zealand 'New'.

  • But they weren't able to make significant progress because the Netherlands was busy

  • being invaded by Germany and after the war the Dutch government prioritised rebuilding

  • the old, rather than building the new.

  • But then everything changed when the North Sea attacked.

  • In the night from the 31st of january to the 1st of February, exactly 67 years ago in 1953,

  • a storm hit the Netherlands with a ferocity rarely seen in this part of the world.

  • Because it was the 50s in Europe, many radio stations, weather stations, and emergency

  • offices weren't staffed at night.

  • So when the warning was sent out that evening of an incoming flood, there was nobody there

  • to listen to ituntil they heard the water rushing through the streets, dragging away

  • houses, cattle, and people.

  • While this area was protected by dikes, they simply weren't strong enough to withstand

  • a storm of THIS magnitude.

  • They were designed for the smaller regular floods occuring in the Netherlands.

  • But this storm broke the coastal defences in 67 locations, with holes up to 3.5 km wide.

  • In total, 1836 died in the netherlands, 70.000 people became homeless, and 200.000 farm animals

  • were killed.

  • The news broadcast the next morning proclaimedThe sea needed just a single night, to

  • prove how powerless humanity is”.

  • 20 days after the flood, the Dutch government created a team of experts tasked with looking

  • into ways of tackling the problem of the netherlands constantly flooding.

  • They called this team of experts: the Delta Committee.

  • Afterall, the Dutch had already created a large dam just 20 years earlier.

  • 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 infrastructureat 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 isdamn 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 againbut 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 sofinally, 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.

  • If you liked this video then please leave a like, subscribe, and hit the notification

  • bell.

  • 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.

The Delta Works are one of the Seven Modern Wonders, They are the largest system of flood

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為什麼荷蘭沒有洪水(Why The Netherlands Isn't Flooding (Anymore))

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    Knight 發佈於 2022 年 03 月 15 日
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