PRESS RELEASE - Envisan finish their 2nd innovative project near Vlassenbroek

Water managers in Belgium and abroad are watching the works in the Sigma zone at Vlassenbroek (Dendermonde) with great interest. Why? More than 1.5 kilometre new dikes was built using an innovative technique. The construction material: 200,000 m³ spoils dredged from the river Scheldt.

Since the summer of 2012, the Vlassenbroek Polder in Dendermonde has been set up as a 240 hectare flood plain. Envisan, the environmental branch of Jan De Nul Group, has recently completed an 800-metre new ring dike. Envisan had already constructed a compartment dike in the same area using an innovative method with which dredging spoils can be reused as building material.

Once the fine sediments dredged in the river Scheldt arrived by barge, this soft material had to be used immediately, without intermediate storage, to build a dike. Specific additives are added to the dredging spoils to give it the required strength and impermeability. By pumping the dredging spoils on land as dry as possible with a special pump system, the environmental impact was minimised.

Thanks to the combination of an interesting cost price, a high level of dredging spoils reuse, the limited impact on the environment and the success of this technically innovative solution, Envisan were able to apply this technique once more, this time for the construction of part of the ring dike near the village of Vlassenbroek. This time, since it concerned a ring dike for the protection of a village, Envisan optimised this technique, developed in-house, even further, so that the construction of the dike met the highest safety and durability requirements. The construction of this part of the ring dike started in the summer of 2014 and, after a winter break, was completed in the spring and summer of 2015. Envisan and Jan De Nul expect to apply this innovative processing technique in the future for other projects in Belgium and abroad.

“A saving of thousands of truck journeys”

Hans Quaeyhaegens (W&Z): “Thanks this innovative technique, W&Z were able to reuse a huge amount of uncontaminated dredging spoils. They were transported by ship, so that the area around Vlassenbroek was spared thousands of truck journeys. Moreover, W&Z had the financial support from the European Fund for Regional Development. Our innovative project in Vlassenbroek didn’t stay out of the spotlight either. In March, a detailed article was published in the magazine of the International Dredgers’ Association.”