Posted January 7, 2019
In recent times, one of the major port improvements in Europe has been the Calais Port 2015 project in northern France, which is intended to make the port future-proof. Only 42 kilometres across the water from the port of Dover in England, Calais is the closest port on the continent to the UK, making it a vital location for cross-Channel traffic. The traffic in the port of Calais has continued to grow, despite the opening of the Channel Tunnel in 1994.
At present, approximately 10 million passengers and 42 million tonnes of goods move through the port, and these figures are expected to grow by another 40%. Without any intervention, the port will become saturated by 2020.
The Calais Port 2015 project involves the creation of 65 hectares of new operational land, of which 45 hectares is reclaimed from the sea. On top of significantly increasing the capacity of the port, the project will also enable the handling of future-generation ferry ships, with a length of up to 240 metres. At present, ferries are on average only 213 metres in length.
A new ferry terminal will be built on the outside of the current sea defence, which will comprise three new ferry slips. The land and the slips will be protected by a newly made three-kilometre breakwater. This will also create an additional navigable port basin of 90 hectares.
Dredging and rock works
Jan De Nul/Sodraco commenced dredging activities in July 2016 with the 8,330kW medium-sized cutter suction dredger (CSD) HONDIUS. The vessel had to dredge a trench through a sand bar in order to be able to carry out the rock works for the new breakwater at this location. This operation, representing some 0.8 million m3 of sand to be dredged was carried out in July and August 2016. The sand was pumped into the reclamation of the new port area.
Once the trench was completed, Jan De Nul/Sodraco could begin the first stage of the rock works, which ran from September 2016 to January 2017. The equipment involved included the split hopper barges GEELVINCK and NIJPTANGH (both 1,800m3), as well as the L’ETOILE, LE GUERRIER, LE SPHINX and TIGER (all 3,700m3).
Furthermore, the side stone dumping vessel POMPEI was deployed and the backhoe dredger GIAN LORENZO BERNINI was used for the profiling work of the stone. During the first stage of the rock works, approximately 700,000 tonnes of material originating from quarries in Norway and Spain was handled.
In March 2017, Jan De Nul/Sodraco introduced its 23,520kW CSD FERNÃO DE MAGALHÃES to carry out the lion’s share of the dredging and reclamation work. The FERNÃO DE MAGALHÃES is a unit that comprises four heavy-duty self-propelled CSDs built in 2010 and 2011.
Each dredger is equipped with three powerful IHC High Efficiency Cutter Special (HE-CS) dredge pumps. This type of pump has been specially developed for CSDs by Royal IHC.
The FERNÃO DE MAGALHÃES was given the task of dredging 3.7 million m3 of material from the sea floor and pumping it to the shore. With this activity, both the required depth in the new harbour basin was achieved, as well as bringing the necessary material to the reclamation area.
Close to the original coastline, the presence of a relatively soft layer in the subsoil consisting of a mix of sand and silt had to be taken into account. In order to put strain on this layer and induce settlement, a significant overburden was applied, ranging from two to seven metres. The largest overburden is applied at the location where an important interchange is scheduled to be built.
Also in 2017, the second stage of the rock works was carried out. This represented an additional 900,000 tonnes of rock that needed to be handled, an operation for which Jan De Nul’s 32,000-tonne fall pipe vessel (FPV) SIMON STEVIN was used.
The other joint venture partners will complete the superstructure of the breakwater and the dry infrastructure of the project. This includes the rehandling of sand overburden within the reclamation area to be levelled at a height of approximately 10 metres above CM (Code Marine or Chart Datum). The completion and delivery of the entire project is scheduled for January 2021.
Source: Start Dredging.com