61 years ago the UK, Belgium and the Netherlands suffered suffered at the hands of a severe flood (Watersnoodramp) caused by a heavy storm and high tides.
Wikipedia has good background but to summarise, the devastation was massive.
The UK death toll exceeded 300 but in the Netherlands, it was over 1,800.
The War had seen many of the dikes used for military fortifications and maintenance activity had slowed down or ceased completely. During the post war rebuilding phase many of the repairs were of the expedient type and it was later noted that some of these areas were the first to give way to the combined effect of storm and tide.


After the immediate rescue and recovery activities had completed there were many gaps in the sea defences to close. Most of these were completed in a relatively short period but some of the larger and more complex gaps would need a great deal of heavy duty construction. Compounding the reconstruction was the twice daily tide and amount of damage.
The Allies had previously used surplus D Day Phoenix Mulberry Harbour caissons for a similar task in 1945 and 1946 on the island of Walcheren so the same technique was proposed. After extensive scale modelling eight Phoenix caissons were floated over from the UK although some were lost in heavy seas during the journey.


Over a period of several months they were used to close the gaps in destroyed sea defences in a number of locations.
[tabs] [tab title=”Phoenix 1″]What happened to them?
One of the more fascinating aspects of this little known story is that they are still there


The actual sea defences no longer rely on the caissons but the Dutch decided to turn them into a museum, a museum that commemorates the floods and those involved.
On 6 November 2003, 50 years after the closing of the last breach at Ouwerkerk, the four caissons and the surrounding area were awarded National Monument status by the Minister of the Interior, Johan Remkes , and from that day were known as the National Monument Watersnood 1953 .
In recognition of the importance of this National Monument, the Foundation Caissons Ouwerkerk has changed its name to Foundation National Monument Watersnood 1953 and the articles have been amended accordingly.
Since 2001 a museum was situated in one of the caissons. The focus of this museum has been on commemoration, remembrance and knowledge. Since april 23th 2009 we use all four of the caissons.
Click here to view the museums website.




The caissons were a decade old when they were used by the people of the Netherlands, the other survivors can still be seen in Portland Harbour, off the Queens Pier.


Not forgetting those off Arromanches.


Swords to ploughshares, concrete ones at least!
Can’t recommend the watersnood museum highly enough… for a mulberry harbour nerd its incredible to be able to walk inside them and look up at the makers marks and construction techniques etc Almost as impressive as the mighty sea defences the Dutch have thought about, designed, funded and built since then to replace them. Puts the Somerset levels debate into perspective. It’s more than just a bit of dredging….
There is also a magnificent newsreel clip of the caissons being manouevred into place and finally close the breached sea wall.
One thing i picked up from the museum notes was that the UK did not gift the caissons but sold them to he Dutch. seemed a bit hardnosed given the circumstances !
I believe there is one in Langstone Harbour (Portsmouth) which broke its back.
DaveS, did a spot of Google and there it is…
http://en.wikipedia.org/wiki/Langstone_Harbour
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