Map of the Zuiderzee reclamation

Even before the barrier dam was finished work started on the first polder. Before the polder dikes could be built unstable foundation soils were removed and replaced with compacted sand fill. The dike was constructed using a double boulder clay core and sand fill. Riprap, asphalt, and basalt revetments were placed on the dike body to protect against wave action. The pumping stations were constructed in the dike at locations where the primary discharge channels were planned. 

Wieringermeer was the first large polder created from the Zuiderzee (see Fig. 84.5). The dike from the tip of Wieringen Island to the mainland at Medemblik was constructed between 1927 and 1929. After removing around 700(10) (24.7(10) ft ) of water the polder came dry on August 11, 1930 creating 200 km  

The second large polder created in the Zuiderzee reclamation was the 480 km (185 mi ) Northeast Polder (see Fig. 84.5). The polder dike runs from Blokzijl on the east to Lemmer on the north. The drained land included two islands, Schokland and Urk. Two rivers in the old land had to be dammed and diverted to drain into the water surrounding the new polder. Construction started in 1937 and the 1.5(10) m (53(10) ft ) of water was removed by 1942. The deepest canals lie 5.5 m (18 ft) below the outside Usselmeer water (van EHiin de Kaste, 1990). 

After this area was pumped dry it was discovered that the groundwater levels in the old land around the perimeter of the newly created polder were much lower. This resulted in a drying out of the old land. They concluded that a peripheral lake between the polder and the old land would have kept this from occurring. 

Eastern Flevoland and Southern Flevoland were the third and fourth large polders constructed (see Fig. 84.5). They were built at different times but share a common dike boundary. These polders included a marginal lake to eliminate any problems with lowered water tables in the surrounding old land. These lakes provided additional recreational benefits. 

---