Subsea Survey Solutions

Maximising time on site to deliver customers more

Not only can a post-installation survey be a requirement set out in the licence issued by the relevant Marine Authority, but also a pre-requisite where cable installation design cannot fully mitigate the risk of cable exposure.

Post-installation monitoring surveys can also be carried out periodically to minimise future threats and identify preventative action that can be implemented, improving reliability and reducing un-budgeted costs.

From a fleet of 16 CTVs strategically positioned around the UK and Europe, we offer these survey solutions to energy developers and owners to provide a detailed insight into seabed conditions. Completing the surveys from vessels already located at the wind farms, make it a cost effective solution that maximises the benefits of time on site.

Customers gain from using vessels and crews with experience of their sites, with many operational approvals already in place. Our survey solution also eliminates transit times to site and minimises risk of weather delays.

OUR SUBSEA SURVEY SOLUTIONS

SCOUR MONITORING

Scour condition monitoring and volume calculations are performed using high resolution multi-beam bathymetry MBES and side-scan sonar SSS surveys around WTG foundations. This is often where tidal currents have removed material which might compromise the security of foundations or exposed cables. 2D/3D images, maps and volumetric calculations of material moved are produced, at acquisition speeds of 3-4 knots.

SEABED SURVEY

The use of multi-beam and side-scan sonar surveys to detect cable exposure and measure depth of sediment cover over cable by comparison of seabed with previous surveys. Use of high resolution MBES digital terrain models, with highly accurate vertical correction for tides to monitor cable depth of cover without the use of ROVs. Acquisition speeds of 3-4 knots.

ROV SURVEY

Cable crossing condition, CPS protection monitoring and depth of burial verification surveys using ROV based tools such as TSS 440/350, Innovatum Smartrak or the Pangeo 3D Seismic system.

BENTHIC SURVEY MONITORING

Analysis of infauna (subsurface) sampled by grabs or cores and the epifauna (above surface) sampled by trawls or dredges, accompanied by the sub-sampling of sediments for analysis of particle size distributions and contaminant concentrations.

OUR KEY CAPABILITIES:

  • Assessing the burial status of the cable and determining cable exposure/free-spanning or monitor existing exposures/spans
  • Identifying cable damage
  • Assessing the burial depth of the cable
  • Assessing scour in the vicinity of the substation
  • Assessing mobile sediment movement and sediment level changes (scour/erosion/accretion) from previous surveys
  • Updating the ground model to review sediment level changes and trends
  • Assessing the condition of existing remedial works
  • Identifying potential hazards in the vicinity of the cable and offshore substation
  • Monitoring identified sensitive habitats
  • Monitoring identified areas of archaeological interest
  • Reporting on maintenance works required
  • Providing seabed information in order to assess any third party compensation claims
  • Delivering consent compliance
  • Delivering third party pipeline, cable or other crossing agreement compliance

Our Latest News:

Posted: 01/12/2017

Global Marine Group completes acquisition of Fugro’s trenching and cable lay business

Acquisition Further Positions Global Marine Group for Significant Offshore Power Market...

Posted: 07/11/2017

Global Marine Group launches new Safety Management System

Global Marine Group (GMG) has launched a new Safety, Security and...

Posted: 12/10/2017

Global Marine Group to acquire Fugro’s trenching and cable laying business

Acquisition further positions company for significant offshore power market opportunities Chelmsford,...

Posted: 08/09/2017

CWind Awarded TP Gate Contract

Two DONG Energy offshore wind farms set to benefit from CWind...

Posted: 05/09/2017

Global Marine Group Awarded Order of Distinction from Royal Society for the Prevention of Accidents

Chelmsford, Tuesday 5 September 2017. The Global Marine Group (GMG), a market...

Posted: 31/08/2017

Global Marine Group Chooses Port of Blyth to Extend UK Footprint

Chelmsford, Thursday 31 August 2017. The Global Marine Group (GMG), a market...

Posted: 17/08/2017

Global Marine Group Secures Cable Contract for Rampion Offshore Wind Farm

Chelmsford, Thursday 17 August 2017. Global Marine Group (GMG), a leading...

Posted: 08/08/2017

CWind Secures Major Cable Pull-in Contract at Merkur Offshore Wind Farm

Chelmsford, Tuesday 8 August 2017. CWind, a leading provider of services...

Posted: 03/08/2017

Utilising the Q1000, CS Recorder Completes Cable Reburial Project in Three Weeks

Chelmsford, Thursday 3 August 2017. Global Marine Group (GMG), a leading provider...

Posted: 03/08/2017

Global Marine Group to Ride Over 200 Miles for Children’s Charity Brainwave

Chelmsford, Wednesday 2 August 2017. Employees of the Global Marine Group (GMG),...

Posted: 03/07/2017

CWind Announces Two-Year Crew Transfer Vessel Extension on Key Offshore Wind Farm Project for Dong Energy

CWind, a leading provider of services to the offshore wind industry,...

Posted: 06/05/2017

Global Marine Group Reports Busy Spring Period

Heading into the summer months with resources engaged around the globe....

Posted: 02/05/2017

CWind Reaches Halfway Point of 15 Month Secondary Works Contract for Iberdrola’s Wikinger Offshore Wind Farm

CWind, a leading provider of services to the offshore renewables industry...

Posted: 25/04/2017

CWind Completes Vital Power Cable Repairs to Reconnect over 2,000 Scilly Islanders

CWind, a leading provider of services to the offshore renewables industry...

Posted: 16/02/2017

CWind Invests in Largest Crew Transfer Vessel to Date

CWind, a leading provider of services to the offshore wind industry,...

Posted: 14/02/2017

Introducing power cable capabilities to the CWind service scope

Positioning ourselves to meet wider customer needs As you may have...

Posted: 13/02/2017

CWind to Deliver Global Marine’s Power Cable Capabilities

CWind, a leading provider of services to the offshore wind industry,...

Posted: 26/01/2017

CWind Supports Centrica Jack Up Operations from Grimsby Hub

CWind, a leading provider of services to the offshore wind industry,...

Posted: 04/01/2017

CWind Provides Crew Transfer Vessels for EON Blade Maintenance Work at Robin Rigg

CWind, a leading integrated service provider in the offshore wind industry,...

Posted: 08/12/2016

CWind provide CTVs for Siemens Blade Maintenance Campaign

CWind, a leading provider of services to the offshore wind industry,...

Posted: 05/12/2016

CWind Provides ROV Subsea Inspections for E.ON at Amrumbank West

CWind, a leading provider of services to the offshore wind industry,...

Posted: 22/11/2016

CWind Wins Contract To Undertake Secondary Works For Geosea At Galloper Offshore Wind Farm

CWind, a leading provider of services to the offshore wind industry,...