The rise of sea levels as a result of climate change and how to defend against flooding

September 3, 2008 12:49 PM

A Dutch government commission came up with a planto prevent flooding in spite of climate change during the next two centuries. Predicting a sea level rise of between 0.65 and 1.3 metres (2.15 and 4.3 feet) by 2100, and up to four metres by 2200, the commission said the chances of flooding multiplied 100-fold with every 1.3 metre rise in the sea level.

The Netherlands, nearly two-thirds of which lies below sea level, must spend up to 1.5 billion euros (2.1 billion dollars) per year over the next century on additional safety measures.
The previous so called Deltaplan was a reaction to the 1953 disastrous flood. It was a $3 billion, 30-year program to strengthen the protections against the sea. The country built an elaborate network of dikes, man-made islands and a 1 1/2-mile stretch of 62 gates to control the entry and exit of North Sea waters into the country's low-lying southwestern provinces.
Previously on mefi

posted by jouke (34 comments total)

Exporting their sea-fighting experiences is going to become a huge growth industry for the Dutch, very soon.
posted by Tomorrowful at 12:58 PM on September 3, 2008 [4 favorites]

Also previously.
posted by Wolfdog at 1:00 PM on September 3, 2008

Couldn't they just buy some other country for $3 billion? I count 23 countries with a GDP of less than $3B.
posted by GuyZero at 1:09 PM on September 3, 2008 [2 favorites]

Awesome post.
posted by goodnewsfortheinsane at 1:21 PM on September 3, 2008

"Dutch dykes in need of massive overhaul"

I can see some tasteful jokes coming out that headline.
posted by Dumsnill at 1:24 PM on September 3, 2008

I always love a good Dick Van Dyke joke.
posted by stavrogin at 1:27 PM on September 3, 2008

Ironically, the fund they are creating is backed by their natural gas reserves.
posted by tomierna at 1:30 PM on September 3, 2008 [3 favorites]

The Netherlands, nearly two-thirds of which lies below sea level, must spend up to 1.5 billion euros (2.1 billion dollars) per year over the next century on additional safety measures.

Really? The problem in The Netherlands is not keeping the seas out, it's getting rid of the water that comes in.
posted by three blind mice at 1:37 PM on September 3, 2008

three blind mice: the article you link was regarding river flooding, very different.
posted by klocwerk at 2:00 PM on September 3, 2008

I blame the windmills!
posted by Artw at 2:10 PM on September 3, 2008

The problem in The Netherlands is not keeping the seas out, it's getting rid of the water that comes in.

That's the day-to-day problem. If ocean levels rise drastically, or if there is a big storm a la Katrina, the problem will immediately become keeping the seas out, and the only way to do that is big, strong dykes.

This is a very interesting subject, thanks for posting. I actually just read John McPhee's piece on the Atchafalaya / Mississippi flood control project (very highly recommended, and, in case you were wondering, yes, New Orleans is fucked), so it's been on my mind lately.
posted by alexwoods at 2:23 PM on September 3, 2008 [1 favorite]

Actually both are problems: keeping seawater out and managing the watermass that flows from switzerland, germany, france and belgium through the netherlands to end in the sea.
posted by jouke at 2:24 PM on September 3, 2008

Previously?
posted by Faint of Butt at 2:35 PM on September 3, 2008

The UK could well look into using some Dutch urban technology to help with the problems they have with housing on their many floodplains.

"The Dutch firm Waterstudio designs houses and other buildings that actually float on the water. As Koen Olthuis of Waterstudio says, in an area prone to flooding, "the safest place to be is actually on the water".

Waterstudio's standard "watervilla" floats thanks to a hollow concrete box underneath it, which acts both to provide buoyancy and as a basement for the house. In most cases the house is moored to the shore on posts sunk into the ground, and, as the water level rises, the house simply slides up the posts."
posted by urbanwhaleshark at 2:45 PM on September 3, 2008

Another Dutch idea for coping with flooding is amphibious houses.

It's just amazing that in the US, the Army Corps of Engineers builds levies to cope with the so-called 100-year flood. That means in any given year, there's a one in 100 chance the levy will be breached, which is not encouraging if your house, your farm, your business, your family are behind it. And with global warming intensifying hurricane activity, some of those levies are only good for the 50-year flood.

Meanwhile, the Dutch have been fortifying their defenses against the sea with nonstop construction since their 1953 disaster, and are planning for more, but they currently have protection against a 10,000-year flood.

One engineering analysis suggests that in the long run, a 1000-year solution for New Orleans would be less expensive than rebuilding to pre-Katrina levels.
posted by beagle at 2:48 PM on September 3, 2008 [1 favorite]

yes, New Orleans is fucked

That issue came up on the Daily Show yesterday or the day before (I'm watching them delayed because I live in the Netherlands), and yes, the Netherlands and Dutch expertise came up.

I'm pretty confident that New Orleans isn't fucked - or rather, not yet. All you really need to do is let in people who know this stuff. When Katrina happened, we offered that expertise, and I'm pretty sure the offer still stands.

What you really need is some competent government, one that would be willing to listen.

It won't be cheap, it won't be easy. I guess telling that to the population is what makes it so difficult for politicians to do this. They'd rather go for the sound bite blaming the opposition. Much easier that way.
posted by DreamerFi at 2:51 PM on September 3, 2008 [1 favorite]

New Orleans is fucked if you want it to be.
posted by Artw at 3:15 PM on September 3, 2008

What those people need is some input from FEMA...with all that money being spent yearly, no wonder they can put a decent military into places world-wide.
posted by Postroad at 3:29 PM on September 3, 2008

I thought there was a distinction in spelling: you can put your thumb in a dike to prevent a flood (according to legend), but putting your thumb in a dyke (without invitation) is just going to get you arrested. A quick search of the tubes finds the spellings apparently interchangeable for the former (though I've never seen the "y" spelling used here in the states), and I've never seen the type-of-person spelled with an "i". Learn something every day.
posted by maxwelton at 3:32 PM on September 3, 2008 [1 favorite]

Waterstudio's standard "watervilla" floats thanks to a hollow concrete box underneath it, which acts both to provide buoyancy and as a basement for the house.

That's actually pretty brilliant. I wonder how much it adds to the construction cost of the house. I further wonder why ideas like this aren't being used constantly in flood prone areas.

If I was looking to build a home in a flood-risk area, I would think that I would like to know that in addition to whatever safeguards the city put in place, I had the extra level of defense against disaster.
posted by quin at 3:44 PM on September 3, 2008

I thought there was a distinction in spelling: you can put your thumb in a dike to prevent a flood (according to legend), but putting your thumb in a dyke (without invitation) is just going to get you arrested.

That's what I always thougt. It's optional, apparently.
posted by Dumsnill at 3:50 PM on September 3, 2008

Quin: That's actually pretty brilliant.

It's why I think we should look to them for a lot of flood-resistance planning. The Netherlands too. I'm sure they had some fantastic scheme to flood some low-lying areas of their country to the detriment to many communities to preserve the integrity of the country as a whole, but google is failing me at the moment. Similar to starting distibuted brush fires to burn off the scrub (and, it was found, to allow the sequoias to repopulate) to prevent a complete inferno.
posted by urbanwhaleshark at 3:58 PM on September 3, 2008

Rumour has it that calling a lesbian "dyke", indeed comes from Hans Brinker's "finger in a hole".

Ironically, the fund they are creating is backed by their natural gas reserves.

Which indeed gives huge problems in the north of the Netherlands, where the gas is won. As the ground sets, and descends by centimeters more per year than was predicted.

On the other hand, the Dutch writer Matthijs van Boxsel has written about this theme in his Encyclopedia of Stupidity, blaming the Dutch that they only have themselves to blame that their country lies so low; because they have drained it so well the ground became too dry and has set too low.

Apart from that, there are indications that there's a huge builders' and developer's lobby involved, in the plans of that governemental commission. Because, if there's money spend on building dikes, there will also be money spend on building activities near those dikes and sea walls.
posted by ijsbrand at 4:07 PM on September 3, 2008 [3 favorites]

Wow, what a radical idea! Thinking ahead! Actual long-term planning and preparing for future contingencies! Those crazy Dutch!
posted by flapjax at midnite at 4:21 PM on September 3, 2008

1,5 million euros per year is of course a trivial amount for The Netherlands.

Bangladesh, there's the problem.
posted by Dumsnill at 4:44 PM on September 3, 2008

jouke, I thought you all were dealing with this by growing extremely tall...
[not Dutchist]
posted by Mister_A at 4:52 PM on September 3, 2008 [1 favorite]

I thought you all were dealing with this by making massive amounts of poffertjes and using those as dike construction materials.
[not poffertjeist]

mmmm... poffertjes!
posted by flapjax at midnite at 5:41 PM on September 3, 2008 [1 favorite]

Waterstudio's standard "watervilla" floats thanks to a hollow concrete box underneath it, which acts both to provide buoyancy and as a basement for the house. In most cases the house is moored to the shore on posts sunk into the ground, and, as the water level rises, the house simply slides up the posts."

And when that happens, I'm cutting my watervilla free of the posts and turning pirate.
posted by Ritchie at 7:08 PM on September 3, 2008 [1 favorite]

"Predicting a sea level rise of between 0.65 and 1.3 metres (2.15 and 4.3 feet) by 2100, and up to four metres by 2200, the commission said the chances of flooding multiplied 100-fold with every 1.3 metre rise in the sea level."

The Dutch are being conservative, optimist or naive? After all, we all saw Al Gore saying that the sea levels would rise 20 feet!
posted by falameufilho at 7:22 PM on September 3, 2008

Metafilter: free of the posts
posted by flapjax at midnite at 8:03 PM on September 3, 2008

Guyzero: GDP is a tiny fraction of the value of a country.
posted by pompomtom at 8:56 PM on September 3, 2008 [1 favorite]

Yeah, listen to pompomtom. Think of the organs!
posted by tehloki at 9:56 PM on September 3, 2008

The problem in The Netherlands is not keeping the seas out, it's getting rid of the water that comes in.

Current forecasts indicate that global warming would lead to greater rainfall in the Rhine valley, and that the rate of precipitation could peak much higher than it currently does. To prevent "pulses" of high water from overtopping the dykes that protect cities along the Rhine, some agricultural land in the traditional floodplain of the river is being 'de-poldered'. That is, it will be allowed to flood during surges. These areas will become permanent national parks and because of their ability to absorb (and later slowly discharge - as the river level falls again) huge amounts of water, they will act as hydrologic shock absorbers.
Emergency flood plains will also be designated in which agricultural activity will be run in such a way that very occasional submersion is tolerable. Bulk chemical storage will not, for instance, be allowed in these areas. If a rare 'super-storm' threatens to overwhelm the dykes of urban areas despite the buffering of the new floodplains, then these secondary areas will be allowed to flood. Some housing may be built here with special permits, which are in theory only granted for projects like the floating houses.
Of course, this is fresh water, so flooding won't be disastrous for agriculture there in the long term.

Electrical infrastructure and pumping stations are already designed to tolerate partial immersion, so that a minor breach cannot (as it did in NO) knock out pump capacity and lead to the whole dyke ring flooding.

To prevent saltwater flooding, there are plans to:
-Use our understanding of coastal currents to release huge amounts of sand in strategic locations off the coast. It will then be naturally deposited and increase the size of beaches and dunes, mimicking the natural formation processes of these protective features.
-Possibly build offshore reefs and islands to break and buffer storm surges.

It will be difficult for any other country to duplicate this, for the same reason that with the best will in the world, Phoenix AZ couldn't be turned into a bikeable, walkable city.
We've invested in our flood defenses (and our bike paths) for many years. Not only would it be financially difficult to duplicate 400+ years of water management overnight, but all our infrastructure and our settlement patterns for hundreds of years have taken this into account. You can't simply slap flood defenses onto Florida (are those houses really right on the ocean, I mean, damn) and make it resistant to flooding anymore than you can make a suburb-looking-for-a-city like Phoenix into a great place to commute on a bike by building a few million dollars worth of bike paths.
Even our consensus seeking politics is a reaction to the fact that you simply cannot pretend that what your neighbour does won't affect you, what if he damages the dykes on his land?


The truth is, all those fun googlemaps driven websites that allege to show which cities will be underwater are based on a fundamental fallacy which appears to equate Bangladesh, Manhattan, parts of London, and the Western Netherlands. We all know that the reality is this: we Dutch have the money and the ability to protect ourselves from the rising water, and we will have even more money after we're commissioned to build flood defenses for large American coastal cities. Bangladeshis will drown - which I suppose is a better way to go than starving to death after repeated saltwater floods ruin their farmland.

On preview: you will all drown beneath the flood of words
posted by atrazine at 11:10 PM on September 3, 2008 [11 favorites]

New Orleans is fucked if you want it to be.

What I meant was:
Even if the Army Corps of Engineers manages to keep out river floods and hurricanes, and pumps out every inch of rain that falls on New Orleans, which is what they do now, eventually the main river will work around, under or over the Old River Control and the Atchafalaya will become the main distributary, the lower Mississippi will silt up and New Orleans will lose its reason for existing. Another fun problem: the delta is disappearing, ironically due to flood control efforts, and loss of the delta means there is no swamp there to absorb hurricanes, or river floods for that matter. It's easy to hate on the Corps, and they should do a better job fixing levees (and maybe hire some Dutch people too), but we are asking them to do something that is, in the long run, impossible.
posted by alexwoods at 12:45 PM on September 4, 2008 [1 favorite]