Van den Herik and NGE-Guintoli recently won a contract from EDF (Electricité de France) for preparing the dismantling of the ‘La Roche Qui Boit’ dam on the Sélune River.
The 15m high and 125m long dam holds a reservoir that occupies about 30ha of land and contains 1.5 million m3 of water.
Van den Herik will be responsible for the dredging and storage of the estimated 210.000m3 sediment.
Unique in this project is the use of geotubes on a large scale. Via tubes, the dredged sediment is transported into the large-scaled geotubes, provided by the German company Huesker.
Halfway it is mixed with biodegradable polymers that help the water separate from the soil. The dewatering process starts immediately when the tubes are being filled.
After dehydration, NGE-Guintoli will open up the geotubes to disperse the dried soil in the surrounding area.
This complete project will take about one and a half year and preparations already have started.
The dismantling will start in 2021 and is planned to be finished in 2022.
This is not the first dredging project for the two companies, Guintoli and Van den Herik have been working together in a former project that concerned the dredging of 300.000m3 sand from a beach near a nuclear station.