2000th Dive Achieved on The Greater Gabbard

Case Study Overview

Support Fluor Ltd, the principle contractor, with all diving operations.

Red7Marine is using the OSV Relume, a DP2 class support vessel to conduct her operations and all equipment and procedures are IMCA compliant. The dive team have work continuously throughout the year and also assist in many other ways including pile cleaning, cable recovery, generator installations and many other non-diving related activities. The dive team have thus far completed over 2000 dives in a little less than two years and the project is continuing beyond this point.

All diving work has been performed in poor visibility and in tidal conditions.

At a glance

  • Location: The Greater Gabbard Offshore Windfarm
  • Date: May 2009 – On-going
  • Programme Duration: 23 months so far
  • Project Number: 2068
  • Value: £ xxx
  • Client: Fluor
  • Principal Contractor: Red7Marine

The Solution

The initial contract was to install J-tubes to the outside of each Wind Turbine Generator (WTG) using a R7M designed bespoke pile based crane. However, as the project progressed, a more varied work scope presented itself. Below is a list of typical tasks carried out by Red7Marine to date.

Diving and subsea work:

  • Ordnance location and disposal
  • J-tube installation and removal
  • Concrete mat installation
  • Dredging operations
  • Activation and removal of Tekmars Teklink cable protection system
  • Reference cell installation
  • Inter Array cable removal and recovery
  • Surveys as directed

All diving works are being carried out using Nitrox instead of air as a breathing medium to extend the bottom times and thus productivity in water depths that average 30m. All work scopes being carried out follow Red7Marine generated procedures and are completed following IMCA good practice guidelines and conform to the HSE Diving at Work Regulations 1997.

Greater Gabbard

Non-diving operations:

  • Navigation light installation and removal
  • Cable recovery
  • Pile cleaning
  • Generator installation and recovery
  • TP access works

Red7Marine personnel have been, and continue to be, intimately involved in all aspects of the contract, where asked by the client. When 3rd party contractors are required by the client Red7Marine has endeavoured to source and project manage
the extra work, often utilising our own personnel to supplement the contractors own work force.

The needs of the client often change, and as can be seen, vary extensively, but Red7Marine have continued to adapt to these changes and managed to step up to the challenge. We remain one of the longest serving sub-contractors on the project and fully intend to continue working on the project until its eventual successful conclusion.

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“Our relationship with Red7Marine and their Personnel through all stages of this challenging Project has been based on partnership and co-operation. A huge consideration was given at the initial phase to identify potential difficulties. This has been followed by development of various scenarios and methods of addressing such difficulties which provided a great benefit during actual works. We look forward to continuing the relationship with the Red7Marine team.”

Kate Sellers, Site Agent BAM Nuttall