One of the purpose-made vessels for this project was Cardium, the behemoth on this photo. Cardium flattened the sandy seabed and unrolled massive pre-fabricated mats packed with sand, gravel and stones, so that each pier could stand rock solid for centuries. Up front sat a 44 meter wide suction arrangement, totalling about 7,000 kW of suction power that gave each mat a leveled seat. The under-mats were roughly 42 × 200 m and 36 cm thick. Handling rolls of that scale demanded tight control of speed, tension and alignment from the electrical drives and winches supporting the lay system. Careful depth measurements determined the exact shape and thickness of the layers of mats that followed. Cardium then placed those made-to-measure additional layers on top to complete the storm surge barrier's foundation.
Van der Leun delivered the electrical installation for this incredible vessel.