Inundation of the Wieringermeer

On 17 April 1945, the retreating German occupying forces inundated the polder of Wieringermeer, the Netherlands.

In 1945 German forces occupying the Netherlands planned to destroy the Zuiderzee Works to cover their retreat. Military reasons for this are still unclear, but it may have been done to deny the Allies a landing area for airborne troops or gliders. In preparation for this flooding, the water level of the IJsselmeer was deliberately raised. The level in the IJsselmeer was 3.62 m above the ground level of Wieringerpolder at the site of the breach, and varied between 3.12–5.12 metres above, across the polder. Inundation had already been used on some Dutch polders but this strategic inundation was shallow and was done by stopping the drainage pumping or allowing water to flow backwards through the pumping stations to give a shallow flooding. The rapid and deep tactical inundation planned for the Wieringerpolder, done by the destruction of a dyke, was new. It was known that even an explosive breach would not be enough, and it would be the enlargement of the breach by the water itself which would cause the most damage.

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