The NorNed Cable is power cable between Norway and the Netherlands which crosses the Eemsgeul. Originally the cable was installed by means of post-trenching into the fine to medium sand of the seafloor. Due to the increase of ship size towards Eemshaven, the Eemsgeul needs to be deepened. In order to keep the prescribed distance between seafloor and Top Of Cable also in future situation, the NorNed cable has to be lowered relative to Chart Datum. Complication for the engineering is that the actual vertical position of the cable is not known.
It is expected the cable must be lowered by approximately 2 meters. Blue Pelican Associates performed a quick scan of the possibilities of deepening the cable and analyse the working methods. Subsequently BPA consultants made indicative estimates of cost and duration and a risk assessment for the 7 shortlisted working methods. Using a multi-criteria analysis 2 methods were recommended for the detailed engineering phase.
Detailed Description of Actual Services Provided by the consultants of Blue Pelican Associates:
identification of methods to detect the position of the cable
shortlisting and analyzing possible working methods