Inundations

Polders (reclaimed land or former peat excavations) lie below average sea level and can easily be flooded with water (inundated) again. There were 87 different polders designated to be inundated in case of war.
For this purpose many special military waterworks were built and more civilian waterworks adapted, in the whole western part of The Netherlands, between 1884 and 1926. Around 35 of these military waterworks remain.

This list only shows two inundation stations (units of the Engineers Corps responsible for the water management of a specific area) as an example.
An inundation station had one or two purposes: the transit of river or sea-water to other inundation stations and/or the inlet of water into the polders.

Inundation station Schagen

Purpose of this station was:
- intake of water from the North Sea (Wadden Sea, near the port of Den Helder)
- transit to the south, to Inundation station Krommeniedijk inside the Defence Line.

Van Ewijck-sluice

Most northern inlet sluice, near Den Helder.

Damsluice below Kolhorn

Damsluice to prevent water to stream out of the canal to the south. Built in 1891.

Ship sluice in Kolhorn

Modification of civil sluice, budgeted or built in 1891.

Sluices at Geestmerambacht

Budgeted or built in 1904. Probably not much remains due to large scale changes to landscape and waters.

Adaptations to sluices in de Anna Pauwlona Polder, Kennemerland and West Friesland

Budgeted or built in 1890. Unknown sluices, probably the existing Groote- of Oudesluis near Zijper-polder.

Inundation station Spijkerboor

Purpose of this station was:
- receiving water from inundation stations Krommeniedijk, Zaandam or Edam
- inlet of water into several polders
- partial inundation of the Beemster polder.

Eilandspolder

Inundated by the Dutch army between May 12th, 1940 and June 9th, 1940.

Inletsluice Eilandspolder

Budgeted or built in 1890.

The inletsluice has been demolished but the changed shape of the canal is still visible.

Sluice De Rijp

Wooden sluice built in 1597 and replaced by a brick sluice in 1625. Modified for military purposes. Restored in 2005-2006.

Graftermeerpolder

Inundated by the Dutch army between May 12th, 1940 and June 9th, 1940.

Oostwouderpolder

Inundated by the Dutch army between May 12th, 1940 and June 9th, 1940.

Polder de Beemster, centre section

Inundated by the Dutch army between May 12th, 1940 and May 25th, 1940.

Bridges in the Beemster

Budgeted or built in 1899.

The Rijper-road functioned as a low dike to contain the inundation water to the south side of the polder. To close the waterways through the road, all five bridges of the tramway were fitted with slots for wooden beams. Only one of these bridges remains.

Polder de Beemster, north-east section

Inundated by the Dutch army between May 12th, 1940 and May 25th, 1940.

Polder de Beemster, south-west section

Inundated by the Dutch army between May 12th, 1940 and May 25th, 1940.

Plunger in the Volger-road - Jisper-canal

Probably built between 1914 en 1918 when the inundation area was made smaller by moving the north border from the Rijper-road to the Volger-road.

Inletsluice in the Southern Beemsterdike

Probably built in 1890 or 1899. It is the largest known existing inlet sluice, which was restored in 2006.

Polder Kamerhop

Inundated by the Dutch army between May 12th, 1940 and June 19th, 1940.

Sapmeerpolder

Inundated by the Dutch army between May 12th, 1940 and June 9th, 1940.

Starnmeerpolder

Inundated by the Dutch army between May 12th, 1940 and May 30th, 1940.

Inlet plunger near Fort near Marken-Binnen

Remainder probably present under secondary road.

Inlet plunger Starnmeerpolder

Budgeted or built in 1890.