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I may be biased because I live in the NL and I live slightly below sea level. But I would be more worried to live on the coast somewhere else that has no history of dealing with these kinds of problems.

In some sense The Netherlands is the only country on the planet to have the political structures in place to deal with rising sea waters.

What do people think Florida is going to do? They're already losing their drinking water and they're still in denial.

And it really is about having social and political structures in place to deal with problems of this magnitude. The engineering questions are largely understood. Build pumps, dikes and create flood plains. We shouldn't focus on the engineering problems. The problem is one of coordination and mass mobilization of political will, and that already exists here.

> What do people think Florida is going to do? They're already losing their drinking water and they're still in denial.

> Build pumps, dikes and create flood plains.

Just want to point out this approach won't work for Florida (and I'm not implying you said it would). The land in south Florida is porous limestone, and the water will just pass under any dykes you build.

> Just want to point out this approach won't work for Florida (and I'm not implying you said it would). The land in south Florida is porous limestone, and the water will just pass under any dykes you build.

Not a problem. Just drive a sheet pile curtain along the retaining wall to force the flow net through a long enough path that the resistance alone reduces the flow volume. This sort of stuff is covered in civil engineering degrees at graduate or even undergraduate level. Google for sheet pile flow net to get the idea.

And by the way, while you claim that Florida is limestone, the Netherlands is just a big old alluvial plain comprised of loose sand.

Is there a solution that would work for Florida?

Evacuation...or build more homes on stilts. When does Florida become America's Venice?

> When does Florida become America's Venice?

Quite an amusing comparison considering that Venice is commonly seen as an international beacon of sophisticated culture and history, while Florida is... well. I'm not American so I'll leave the rest up to the reader.

/r/FloridaMan is a pretty accurate depiction of how we view Florida. That and Disney World.

> Venice is commonly seen as an international beacon of sophisticated culture and history, while Florida is

...similar in that it is also a top tourist destination.

> or build more homes on stilts

Indeed there are a number of houses that are built on stilts for flooding purposes.

Nowadays that's very uncommon; housing developments often built up the ground enough to mitigate the equivalent flooding risk.

> What do people think Florida is going to do? They're already losing their drinking water and they're still in denial.

That has been going on for decades, and has more to do with the population load on the water supply draining the aquifers than it does climate change. The drinking water table is already below sea level. At worst, climate change is hastening the inevitable.

> the only country on the planet to have the political structures in place

New Orleans is largely below sea level.

(Though maybe Katrina proves your point.)

> They're already losing their drinking water and they're still in denial.

As a former Floridian, that's news to me. Any links?

The groundwater is enough to get that I know a number of people who have their own wells. (That plus a generator is really nice post-hurricane.)

Agreed - I'd say most of the world will be in deeper trouble than the Netherlands since they've been completely ignoring these issues. Most of the coast of Florida comes to mind. The number of homes on small canals that connect directly to the ocean is mind-boggling.

Further, in a worst case scenario where you need to lose a lot of arable land, the Netherlands has zoned itself so that you could "afford" to lose that land while protecting denser cities. At a certain point I see the Dutch putting soil on barges topped by greenhouses and growing on top of the water if it came to that haha.

Of course all of this might mean a significant shift in how the country feeds itself, but the layout is such that you could shift a small minority to denser "protected" places (where more investment might be focused in a worst case scenario) if significant flooding were a problem.

> At a certain point I see the Dutch putting soil on barges topped by greenhouses and growing on top of the water if it came to that haha.

Stop laughing, that's been done:

https://www.floramedia.com/netherlands/2017/01/11/floating-g...

Interesting! Does this handle storms? I suspect we'll see a lot more storms and much higher waves along with the increase in sea level ...

The Dutch are somewhere high on the top 10 net international food exporters. In absolute terms

We could lose a lot of farms and still feed ourselves.

Just did a little bit of a napkin calculation, how much energy would it cost to pump the entire flow of the Rhine 2m higher?

2m head difference, 20_000m3/s flow Due to head difference: 1000kg/m3 * 20_000m3/s * 9.8kgm/s2 * 2m = 392MW

Accelerating to 5m/s: 0.5 * 1000kg/m3 * 20_000m3/s * (5m/s)^2 = 250MW

That is at 100% efficiency. But knowing a modern container vessel has 60MW installed power, and a large coal powerplant (we should be closing those by the way) is about 1GW, this is in the order of magnitude of achievable. Biggest pumps I know of are 5MW (and for higher pressure/velocity, not low pressure/high flow) but if we really wanted to this could be solved

You'd need to be able to deal with peak-flow to some extent.

Either he's already worked that in (20K cubic meters per second) or we can correct for it, the normal 'debiet' is about 600 cubic meters per second, the annual average is 2200, the peaks observed are about 12K.

Another big river to count with is the Waal, which does about 3/4 of that and then there are the Lek, the Maas and the Schelde, all of which are yet another doubling. So there would be a substantial amount of energy involved here.

I'd say the pump capacity and maintenance would be a bigger hurdle than the energy involved.

The largest pumps we have right now do about 250 cubic meters per second.

https://deafsluitdijk.nl/projecten/vergroten-waterafvoer/hoe...

I'd say that that is manageable.

The Rhine is 2,000 cubic meters per second, not 20,000.

From memory I believe the "Ruimte voor de rivieren" project was designed for peak discharges of around 15k m3/s, but could very well be wrong there. Normal discharge is much much lower. Just wanted to see if the extreme scenario is remotely feasible (which I would say it is, though it's pretty far out).

But if there is enough buffer capacity then of course you only have to dimension the pumps for longer term average high discharge, and not peak discharge.

Edit: Just found this: https://edepot.wur.nl/84989

1/1250 year Rhine discharge at Lobith is found to be and as higher discharges will cause major flooding upstream instead of reaching Lobith directly this should be about the max to expect. Such a peak discharge would be part of a high water period with discharges up to 15 consecutive days of >10.000m3/s, so you would need a pretty big buffer.

you do know the deltawerken were only built with a maximum of 40 cm sea level rise in mind, right ? and we're now thinking of about 100 cm by 2100. true, that does not mean the netherlands will disappear right away, but we will see more flooding than before 1953, especially with extreme weather getting more extreme.

so the question is more whether it will be economically viable to keep the land dry. personally, with the more pessimistic IPCC scenarios in mind, we will come to the point where that decision needs to be made. not in my lifetime, most likely not in yours, but still.

as to your last sentence : we have never seen a scenario like the ones now looming over us.

They were built with that in mind, yes. But since then they've been raised several times already and there is continuous maintenance on weak points.

The real problem is the rivers, keeping water out from the seaside is actually a simpler problem than preventing the interior from being flooded once the rivers are substantially below sea level themselves.

Sea dikes and fortifications can be raised (at a cost), but river dikes can't really be raised easily and besides that the water needs to go somewhere. And I did write that on larger time scales there is a real risk, and I believe that anything over several meters rise sustained would be a serious problem and would cause some of the land to revert back to the sea.

But long before then you'll see the same in other countries, Italy, the UK, the USA, France, Germany and Spain all have areas that would be much harder and earlier hit than NL because they have no fortifications whatsoever as a starting point and it would take decades to plan and construct them.

the weak points (like the haringvlietdam and maeslantkering) can't (easily) be raised. and yes, the rivers will be a problem when we need to close the maeslantkering for extended periods of time when the sea level rises. it doesn't matter where the water comes from : the sea or the rivers, it will cause severe floods at some point.

I guess we differ on the 'economically viable' part. but in the really long run (say greenland being free of ice) my guess is no amount of money is going to save the netherlands.

In the really long run everything humans have ever made except for the pyramids is unstable. It would be really strange if the current living generation is somehow the exception. Houses are built for a couple of decades, they sometimes stand for a hundred years or more but that's not the rule and should not be taken as guidance for the future. Companies can move if there is enough time.

What will happen is that at some point - still quite a bit into the future - humanity as a whole will have to adjust to a new coastline and as long as it is economically viable they'll try to milk the structures already built. But in the end, on that timescale it is a non-event.

A bigger question will be how we will house and feed a 10 billion plus number of human beings on a reduced landmass with all the 'good bits' already taken. There will be wars and famine in that future and I don't think we will be able to avoid that forever. Again, history is full of upheaval, we certainly won't have seen the last of it.

But to suggest NL will disappear in the next couple of years/decades is not in line with my expectations based on what I know about this stuff. (More than most, less than what I would like to know but there is only so much time.)

As for the rivers, pumping out the water forcibly would allow the surge barriers to remain in place but would severely disrupt the economy (harbors inaccessible) and would require pumping capacity that we currently do not have (those rivers carry an enormous amount of water).

What is cheaper: building artificial dams and islands off the North Sea coast (for example), or re-settling 7 million people while simultaneously losing all your economic output?

The cost for resettling will mostly be shouldered by the people of the Netherlands, that's how migration works: you pay up, you walk out on your own, or you stay behind in whatever misery you are tying to escape.

> But long before then you'll see the same in other countries, Italy, the UK, the USA, France, Germany and Spain all have areas that would be much harder and earlier hit than NL because they have no fortifications whatsoever as a starting point and it would take decades to plan and construct them.

No one here is arguing whether they can do anything about it. We are arguing about whether the Netherlands can do it. I'm pretty sure that anyone that believe that the Netherlands will disappear under water will agree that all theses coasts you mention will disappear too.

The point is that they will disappear long before NL and yet here we are discussing the one country that has spent decades preparing for rising sea levels disappearing.

> that has spent decades preparing

And that's a major part to argue about, whether it's a fight that's worth it or not.

We have seen exactly this scenario before, only this time the expected water levels are a few decimeter to a few meter higher (depending on the time scale). It's not like the delta works are the technological limit to what we can do. At the time, they were designed to meet the expected requirements and no further.

If the requirements change, we will rebuild them to the new requirements.

if the requirements say 7 meters (the sea level rise if greenland is ice free) building higher dikes will not work. and although that is a long-term scenario, it is not unlikely. hence the 'not if, but when' in the article.

Why won't dikes not work?

I wonder about this too. We have several dikes already that are much higher than seven metres. From everything I hear, we're not anywhere near the limits of feasible dike height, not in terms of engineerable strength nor in economic feasability (they're mostly just earth walls, after all).

That, and dikes need not be made of earth, they can have concrete as well.

The biggest risks with dikes are seepage and shifting, especially a problem with old river dikes before we properly understood how to make them.