• September 4, 2024

30 hectares of the Valley of the Grote Beek hydrologically restored

A lot has happened in the Valley of the Grote Beek during the last few months. LIFE Multi Peat's field team restored the peat at hyperspeed. As many as 30 hectares have already been hydrologically restored!

The biggest drainage in the area is through ditches in the peatland. To prevent this, these ditches will be closed. However, in many places these ditches are barely accessible, or there is too much forest on top of them for a crane to just reach them. This is why our field team braved the peat at the wettest time in the past 30 years and manually filled up all these ditches where they enter the Grote Beek. This way, the ditches can silt up on their own and water is retained within the area. During wet periods, the water still runs off gravitationally.

As many as 54 ditches, good for a total length of 5km of drainage channels, were filled up. This results in a total hydrological restoration of 30 hectares of alder swamp forest. Of course, it remains to be seen whether this is effective enough to stop the drainage completely. This summer we will see which parts succeeded well and where adjustments are still needed. 

Various techniques were tested to plug the canals. 

• Some ditches were closed using sandbags, or a combination of sandbags and local soil/branches. 
• Other ditches were closed using branches and wooden poles to keep the branches in place, whether or not combined with local soil and additional bags of sand.
• The different techniques used will be evaluated at the end of the project and the best (and worst) practices will be described.

Despite the very wet winter, water levels in the area were not even that extremely high. Therefore, it is ideal that the water present at the moment can be buffered as much as possible in the peat soil. The exact effects of this hydrological restoration will become clear within a year, when we can compare the detailed data from the monitoring wells with previous years.