Periplus provides assistance: BritNed Interconnector project - 2010
Periplus was involved on several fronts in the BritNed Interconnector project. The project comprises the construction of a high voltage cable between the Maasvlakte in the Netherlands and the Isle of Grain in Great Britain. The cable, which has a length of 260 km and a capacity of 1000 megawatts, is installed with the purpose to increase the certainty of the supply of power in both the Netherlands as Great Britain. The installation of the cable was done by Visser & Smit Hanab commissioned by the Swedish ABB.
Sand dune rectification
The first contact Periplus had with the BritNed project was in the summer of 2009. The Dredging Internationals Pearl River needed to remove the tops of sand dunes. This was necessary as the sand dunes on the route would constitute a major obstacle for the cable which has a limited flexible nature. Thus by removing the tops excessive forces on the cable are avoided, thereby preventing damage to the cable. Periplus yielded a hydrographic surveyor for the project, who was responsible for mapping the work that was carried out at the bottom of the North Sea.
Maasvlakte
In the winter of 2009/2010 the cable, which has already been placed on the Dutch side, was buried. The burial in the nearshore area was done by means of a so-called jet system. Here the cable using high pressure water jets buried in the sand from the bottom of the North Sea. This part was conducted by ACTA Marine using the Coastal Worker. Periplus was approached by Visser & Smit Hanab to provide people aboard the Coastal Worker to coordinate the work on their behalf.
Isle of Grain
On the British side, the cable was laid in the summer of 2010. The cable route was called here by the London Clay, a layer of clay with very stiff characteristics. Before the cable could be laid, a trench of approximately 1500 meters was dredged by Boskalis Westminster Dredging using the back-hoe dredger Maricavor. After the cable was laid in the trench, the cable was covered again with the previously dredged clay. For this dredging Visser & Smit Hanab approached Periplus again to observe the dredging operation on their behalf.