Land reclamation

The farmers' method 

At an early stage the farmers in the north of Groningen and Friesland discovered that land reclaimed from the sea by creating polders was fertile agricultural ground. From the 17th century they started a simple type of land reclamation. Once the ground outside the dikes had become sufficiently silted up, they dug deep narrow ditches.

This enabled the water to run off more quickly at ebb tide and the land dried out. This made it easier for the silt to stick to the underlying ground and gave plants the chance to establish themselves. The plants, such as marsh samphire, trapped the silt, thereby raising the level of the land even further. 

The 'Schleswig-Holstein' method

In a context of job creation around 1930 the government put the unemployed to work in large-scale land reclamation projects using the 'Schleswig-Holstein' method. The workers built a network of  brushwood off the coast so that the silt brought in by the sea could deposit.

The brushwood dams consisted of two rows of poles with the space between the poles filled with interwoven brushwood, thus creating deposit fields measuring 400 by 400 metres.
You can still find the half-rotted rows of poles that went to form the brushwood dams in a few places in the southern part of the Lauwersmeer National Park. And if you look closely at the landscape, you will see the regular, straight, rectangular pattern of the former deposition fields. The best place to observe this is from the lookout mound on the Zoutkamperplaat.