Unexploded Ordnance Presents Dredging Challenge
A dredging project currently underway by the Dutch contractor Martens and Van Oord in Cadzand, the Netherlands presents quite a challenge: unexploded ordnance (UXO).
The village of Cadzand is located in the south west of the Netherlands, on the shores of the North Sea. Its old marina entrance needed to be updated and the harbor was to be deepened. Not a simple job taking into account that conventional Second World War explosives were hidden in the seabed. Martens and Van Oord was up for the job – using Damen’s DOP submersible dredge pump in the process.
The DOP350 was attached to one of Martens and Van Oord’s pontoon-based excavators. The DOP pumped the bottom material – sand and occasionally UXOs – to a reinforced screening installation. From there, another Damen pump was used to bring the screened sand further to replenish the nearby shores. The choice for using the DOP was a simple one: the submersed dredge pump ensures a continuous process (in UXO-areas) contrary to mechanical dredging.
For sand mining purposes, a somewhat customized sand mining head with plenty of jetwater was fitted. This DOP head was designed for mining a maximum concentration using pressurized water to fluidize the bottom material.
