Project Description

Hydrofix were contracted to provide a range of technical support services to assist in the installation design of three power cables between the Scottish Mainland and Islands. Each cable route lay in challenging areas in terms of geology, bathymetry, UXO risk and infrastructure.

Hydrofix produced a desk-top study (DTS) for each of the cable routes detailing the solid and quaternary geology; metocean influences; fishing and aquaculture activities; shipping; and other anthropological influences. In addition, along with our preferred UXO consultancy partner, we also provided summary UXO risk assessment, and, where the risk was deemed significant, a further Detailed Risk Assessment (DRA).

As part of the data gap analysis, Hydrofix, along with representatives from the client and other contractors visited the proposed cable landing sites in order to assess their suitability and investigate other potential landings. These findings were presented as appendices to the desk-top studies.

Hydrofix assisted the client in producing technical work scopes for the site surveys and provided technical review of the winning survey contractors paperwork and proposals to ensure their suitability and to clarify any issues or omissions well before the start of siteworks to maximise productive site time.

The siteworks comprised topographic survey, drone intertidal survey, shallow nearshore works, offshore geophysical and UXO works and geotechnical sampling. Hydrofix provided a Client Representative on all vessels and for each of the land components. As Hydrofix oversaw all of the collection and data QC aspects, this ensured that all of the data collection adhered to the same standard and any information, issues or variations were clearly and easily carried between vessels and work packages.

Hydrofix actively sought data processing samples from the survey contractor for QC to ensure that the processing methodologies were suitable. Technical support was also provided to the processing team in order to maximise the information provided by the data. On completion of the survey reports, Hydrofix provided initial QC of the reports for the client and liaised with the survey contractor to ensure the highest quality.