Nord Stream has completed an external inspection of the two pipelines. The job was executed using an ROV, equipped with digital cameras, specific sensors and operated from a dedicated support vessel.
The visual and instrumental (geophysical) inspection was performed on the whole length of the pipelines through the Baltic Sea.
The objective of the inspection survey was to collect high-quality data to assess the integrity of the two pipelines through the analysis of several factors: accurate position of the pipelines (vertical and horizontal), depth of burial into the seabed, possible free-spans, condition of the cathodic protection system, verification of existing cables and pipelines crossings, status of intervention works (settlement berms).
The results confirm that the pipelines are still in a period of settlement, as expected, and that all changes are in agreement with the design parameters.
The ROV also recorded the position of cultural heritage sites in the vicinity of the pipelines, and confirmed that the sites were not affected by the presence of the Nord Stream structures.
The survey was conducted between May and November 2014 and it is planned to be performed again in 2015.
At the beginning of 2014, DeepOcean was awarded the contract for inspection of the Nord Stream gas export pipelines in the Baltic Sea by Nord Stream AG. The contract is for two years in 2014 and 2015 and includes the full external inspection of the two pipelines using ROV and ROTV methodologies.