Cable & Pipeline Route Surveys

Gardline provides geophysical, geotechnical, environmental and UXO surveys for the following submarine cables and pipeline types:

  • Oil and gas pipelines and flowlines - both in-field and export routes to shore connections
  • Telecommunication cables - festoon, coastal and/or short distance systems and long distance repeatered inter-continental systems to full ocean depth
  • HV electric DC interconnector cables - generally longer distance systems connecting two or more coastal states
  • HV electric AC/DC export cables - connecting OWF's with shoreside grid connection points
  • HV electric AC/DC inter-turbine cables - connecting wind turbines or other generators within an offshore renewable development. 

Depending upon a client's specific requirements Gardline's resources can also accommodate post lay cable/pipeline inspections. A wide range of marine survey tools are available for operations from shallow to full ocean depth, including:

  • Digital side scan sonar - Edgetech dual frequency multi-pulse 100 - 600 khz
  • Sub bottom profilers - Geoacoustics hull mounted multi-element and/or Seaprobe deep towed combined side-scan/sub-bottom profiler systems (3.5-7khz with chirp), shallow towed single and multi-channel recording, 300-2KJ Boomer/sparker systems for increased performance in hard soils. 
  • Geometrics G882 magnetometer
  • Multibeam echosounders: Kongsberg and Reson systems including shallow water EM2040/7125 (200-400khz), medium depth EM7 10/7160 (50-70khz) to deep water EM302/122 (12-30khz) systems. 
  • COTS and in house processing and interpretation software
  • Piston and Vibrocorers
  • Cone penetrometers
  • Grab samplers
  • Drop downn camera - digital stills and video
  • Inspection class ROV with a range of tools including depth of burial using TSS 440/350 and Innovatum Smartrak systems. 

Onboard processing, interpretation and mapping services are available for larger projects or as required. We also operate a dedicated onshore facility in Great Yarmouth for final report, charting and GIS production, as well as environmental and geotechnical data analysis, laboratory testing of seabed samples and engineering analysis burial assessment.