Protection against flooding and drought

The Demer valley in the municipalities of Herk-de-Stad, Lummen, Halen and Diest forms a natural basin where more than half of all the water of the province of Limburg comes together. In recent years, the water storage function of the area has been further expanded by the VMM. In total, more than 10 million m³ of water can now be stored. This prevents flooding. It also gives the water a chance to penetrate the soil, which in turn helps in periods of great drought.

​

                                                                           Confluence area

                                                                                              (project area in red)

​

This makes the area a unique confluence area

where special grasslands with rare animal and plant

species occur, which are bound to natural flooding. 

​

For centuries, the extensive valley landscape has

served as a crucial buffer for the water safety of the

inhabitants of the Demer basin. Even today, the major

floods of recent years (June 2016, November 2010, February 2002, September 1998, ...) remind us of this. 

​

That is why LIFE Delta also pays special attention to water management: stronger nature goes hand in hand with water safety. Nature will absorb the water and allow it to penetrate the soil. This prevents flooding and feeds the groundwater table. This, in turn, helps to counteract dehydration during periods of long drought. Due to climate change, there will be an increased chance of both heavy rainfall and long periods of drought. 

Water drained too quickly

​

Already from ancient times, people have tried to control the water in this valley. At first, these efforts were limited to the construction of a drainage network of ditches and locally, dikes were built to contain local flooding. But gradually the interventions became more important.

From the 17th century onwards, the watercourses of the Herk, the Velpe, the Gete and even the Demer river were re-routed in several stages to drain the water as quickly as possible, as to keep the valley relatively dry for agriculture.

Further dyke heightening, bed deepening and canalisation continued over the years. From 1975, around 90 hectares of hay meadows in the centre of Schulensbroek were excavated for the construction of the E314. The Schulensmeer, with a depth of up to 7 m, was a fact.

In order to collect the floods from the Demer, the Gete, the Velpe, the Mangelbeek and the Herk at a central location, a controlled flood area was created in both Schulensbroek (early 1980s) and Webbekomsbroek.

​

​

​

​

                                                           Floods at   < Webbekomsbroek      &      Schulensbroek  >