3.400.000 m3 of sand backfilled within 9 weeks …
i.e. an average of 55,000 m3 per day !
The dredging Company Sodraco, member of Calais Port 2015 Design and Construction Joint Venture and subsidiary of Jan de Nul group, backfilled the ripraps at this very high production rate to finalize the future platforms of the port of Calais. This operation was carried out with the CSD Fernao de Magalhaes, one of the world’s most powerful cutter suction dredgers.
This dredging volume made possible to create the future basin at a rating up to – 11 CM (Cote Marine), 11 meters below the lowest annual sea. It has to be added to the 750,000 m3 already dredged during the first dredging campaign in 2016 to have 45 hectares of platforms created : 4 hectares for the Western inner embankment (260,000 m3) and 41 hectares for the Eastern inner embankment (almost 4 millions m3).
No other material will be required to create this platform, as one of the project guiding principles since its launch is based on the right balance between excavating works and backfilling to create platforms.
Sand is layed on top of some platform areas over about 4 meters to accelerate its settlement and ensure its long-term stability. This overload will then be distributed on the extension site for platform final rating. Other platform areas made up of greater thickness backfill, will have specific compaction operation to achieve the bearing capacity.