CT Offshore was contracted to perform remedial work on a power cable at the Walney Offshore Wind Farm in 2013. The scope of work included recovering the old cable, installing a new replacement cable, and burying the cable using various vessels over the course of 12 days. The project was completed efficiently and cost effectively to the satisfaction of both CT Offshore and the client.

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Case Study
Walney OWF (2013) – Remedial work 1 PCC cable,
Cost Effective Turnkey Solution
In spring 2013 CT Offshore was contracted to carry out remedial work at 1 PCC cable at the Walney
OWF. The cable laying vessel was rapidly de-mobilised from her work at the London Array OWF, and
prepared for this new task.
The project was carried out in a very cost effective way, smooth and professional, to the satisfaction of
both ourselves and the client.
1. Scope of Work
Remedial work at 1 PCC cable including cable recovery, scrap of old cable and replacement of new.
 Scrap cable recovery
 Cable load out
 Pre-lay Multibeam survey (MBES)
 Cable installation
 Post-lay inspection (PLI)
 Optical time delay reflection (OTDR) test before termination
 Post-lay burial (PLB)
 Post-burial inspection (PLI)
 ROV post-burial survey
CT Offshore provided documentation for all Procedures, HSE Statements, Project Management, Site
Management incl. management of the works performed by subcontractors.
• Rigging and pull-in team, incl. rigging arrangement winch etc.
• Dive spread
• Crew vessels: 1 x VPii or MPC 20 t.
• Tester/termination team
Vessels and equipment utilized
Cable Installation: CLV SIA
Survey: MV SANDER 2
Trenching: MV NICO (ROV CTO 103)
Execution period 2 May – 6 June 2013 (12 days charter in total)
Cable load out, harbour Handled from Hartlepool, UK.
Source: WPAP system, Walney P-13-002. Total hrs. of operation: 101 hrs. 33 min. (ex. mob./de-mob)
26%
39%
15%
12%
8%
Time spent in %
Scrap Cable Recovery, SIA Cable Installation, SIA
Cable load-out, SIA PLB, NICO
PLBI survey, SANDER 2

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CLV SIA installing the PCC cable at Substation, Walney OWF – May 2013.
MV SANDER 2 assisted with PLI MBES survey
To carry out the post lay burial inspection (PLBI) our
survey vessel MV SANDER 2 assisted.