The end of February saw the installation of the seventh of the 18 caissons that are forming the protective belt of Portier Cove. The land extension project will allow the construction of much-needed Monaco villas and apartments.
The Portier Cove project is progressing well despite the setbacks caused by bad weather in late 2018. “We are on a schedule in line with the revised plans,” says Christophe Hirsinger, Director of Bouygues TP Monaco. “All the 18 caissons that make up the perimeter ring of the project are still scheduled for the end of July.” Once the caissons are all installed, the public will have a better idea of the scope of the new eco-district, even though the construction of new Monaco villas and apartments is still a long way off.
“Only the first caisson has been partially de-ballasted so it could be repositioned; the others were all installed in their final position at the first attempt,” says Mr Hirsinger with satisfaction. The vibrocompaction and clipping of the backfill for the caissons of Portier Cove is now complete. The improved weather has enabled the team to move ahead with the levelling that is necessary before the caissons can be installed. The Tertnes, the boat responsible for balancing the caissons and preparing the backfill, is now focused on the former task. Two other vessels, the Rhine and Omvac 8, are taking care of the backfill.
“With 9,000 tons being poured each week, we will need around 20 weeks to transport and position the 180,000 tons of material still needed to complete the backfill,” says Mr Hirsinger. The Rhine, which has a loading capacity of 9,000 tons, is travelling back and forth between the port of Toulon and Monaco but stays outside the busy Portier Cove site. The smaller Omvac 8, takes the material from the Rhine to the Monaco site. Each round trip takes two hours.
The installation of the PP265, which will feed the thermal loop for the Société des Bains de Mer and the NiBox by drawing water from a depth of 15 metres, is expected to be complete by the end of April. Work is underway at Larvotto on another outflow, PP330, which will feed the eastern side of the Principality.
A new vessel, Felipo is working on the removal of rocks along the current coastline. Last May, 33,000 tons of rocks were removed and the 40,000 tons remaining will be taken away before the end of April. They will be used to create artificial reefs close to the shore.
The barge Edmond has started to remove the hooks and plugs that are attached to each caisson before they are towed between Marseille – where they are manufactured – and the Portier Cove site. The plugs prevent water from penetrating the perforated section of the caissons during their journey.
The multiple round trips made between the port of Toulon and Monaco will result in the transportation of more than 900,000 tons of material. Meanwhile, in Imperia, Italy, the Larnaco is loading blocks of between 0.3 and 1 ton. These are transported to the Portier Cove site to create a shell of rocks on the sea-facing side of the caissons and the protection of their backfill.
Based on an article by Georges-Olivier Kalifa published in the Gazette de Monaco on the 22nd of February, 2019.