SK4 & NorNed protection survey

This year’s survey campaign for Statnett was granted to MMT. The aim of the offshore survey is to provide Statnett with a Terrain Model (DTM) of the cable and associated trench and berms (where present), as well as a DTM of all engineered crossings including all installed protection. The survey will also provide the location and depth of burial of the cable. The SK4 cable protection survey is performed for both Statnett and Energinet.DK.

MMT has previously performed detailed pre-lay survey for the SK4 cable and have a comprehensive knowledge of the conditions in order to achieve an efficient and safe survey for Statnett.

The cable tracking operations will be conducted from the DP2 vessel Stril Explorer using the WROV Supporter mounted with a TSS. The survey will begin with the SK4 cable tracking operation from approximately 10 m water depth offshore Denmark to the Norwegian landfall at Kvivika. The ROV will be fitted with a multibeam echosounder, side scan sonar and a TSS cable tracker and a high definition video system.

Following the SK4 operation the NorNed cable will be surveyed on Statnett’s ownership of the NorNed cable. The survey will provide location and depth of burial of the cable, identify and analyses any exposed, freespanning and shallow burial sections of cable, identify possible damage, locate debris and produce a bathymetric and cable burial difference model from existing survey data.

An additional separate survey for a possible future cable corridor will also be performed by MMT. This survey takes place in Gandsfjorden (Stavanger, Norway) and the purpose is to find suitable routes for up to 10 single core cables. This survey also include geological sampling and they will be collected by a 3 meter long gravity corer.

MMT looks forward to this project and are delighted to work with Statnett again. This project will also be in close cooperation with Reach Subsea for their ROV expertise.