The Ecodelta pumping in the Maashaven
On this day, the first load of sand, which had been dredged from the North Sea, was brought to the Maashaven by a trailing suction hopper dredger (TSHD).
The dredger in question is the Ecodelta, a 5,900 m3 TSHD owned by Van der Kamp from Zwolle and chartered by main contractor of the project: Van den Herik from Sliedrecht.
Over the next few weeks, the Ecodelta will make several trips, transporting some 5,000 m3 of sand each time, from the mining location in the North Sea to the Maashaven.
This represents the first stage of the underwater filling operation, during which a 2-metre-thick layer of sand is applied.
This will bring the seabed in the eastern part of the Maashaven basin from 6 metres to 4 metres below the average water level (NAP).
For stability reasons, an interval of three months is required between each stage of the filling operation.
After three stages, it is scheduled that a level of 1 metre below NAP will be reached.
The Sientje with spray pontoon
A floating pipeline is used to pump the sand from the TSHD to the spray pontoon.
Stages 4 and 5, which cover the above-water part of the filling process, can only be carried out after a layer of light material consisting of volcanic pumice (Bims) has been applied.
This is required to guarantee the stability of the nearby metro line by reducing the forces acting on its foundation.
Furthermore, vertical drainage is applied to speed up the settling process of the sand filling.
Once stage 5 is complete, the average sand level will be around 4.35 metres above NAP.
But, the design also includes a lookout hill of 9 metres in height.
In total, the project requires the delivery of some 400,000 m3 of sand.
Meanwhile, other activities that have started in March and April, such as installing a sheet pile wall and placing rock, will continue.
The project is scheduled for completion in 2028.