DOP Submersible dredge pumps

DOP350 deepening the river Maas in hazardous circumstances


Location: River Maas near Venlo, the Netherlands

Period: Q4, 2009-Q1, 2013

Challenge: Dredging a site littered with WWII ammunition

Solution: DOP350 with sand mining head (adapted)

Contractor: Martens en van Oord for Rijkswaterstaat

Dumped WWII ammunition added a special touch to this 2.500.000 m3 dredging project.

The river Maas needed to be deepened by some 3 m over the length of several kilometers. By increasing the rivers flow profile it can accommodate higher water flows; this prevents flooding of the area. The challenge was not so much the dredging depth or the type of soil. The main concern was the presence of WWII ammunition.

View of the full floating plant

To ensure the safety of the team, Martens en Van Oord developed a specific dredging method. This included adaptations to the standard suction head of the DOP350, plus reinforced connection of the DOP350 to the excavator’s boom. The DOP350 was powered by a ICE power pack type ICE800.

DOP350 attached to pontoon based excavator

All sediment was processed, resulting in some 1.200 pieces of ammunition which were handed over to the Dutch armed forced for disposal. The dredged material was treated and sold as quality bulk sand in various degrees from the Martens en Van Oord Moerdijk premises.

Dewatered sand is transported to a barge alongside

After completion the pontoon-based DOP350 & excavator combination continued the job further downstream.