Following on from the recent Breakwater Project Review, contractor Boskalis Westminster mobilized at the end of July for the last stage of the Cowes Breakwater build, which will be completed in October 2015.
This involves a final reshaping of the breakwater’s gravel core, bringing sections into profile before applying layers of small rock that act as a filter to prevent the gravel migrating out of the core structure, reported Cowes Harbour Commission (CHC) in a release.
Following this, a rock armour layer consisting of 300-1000kg rocks will be installed to provide long-term weather and wave protection. A total of around 45,000 tonnes of rock will be brought from Cherbourg in France and transported by barge to Cowes.
A temporary dock has been constructed on the northwest corner of the breakwater to facilitate the mooring of the rock barges. Approximately two rock barges are expected to arrive per week and will remain on station for around 18 hours at a time.
The rock barge will be offloaded by excavators and shovels on the western end and northern side of the breakwater. Excavators located on the breakwater will position the rocks working anti-clockwise, starting on the southern face working to the east and then back along the northern face to the west, bringing the breakwater to its final profile and finished appearance. The process involved for the discharging of rock from the barge may occasionally necessitate contractors Boskalis Westminster operating during night-time hours.