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 4 CTVs strategically positioned along the Taiwan coast, and supported by our parent company’s experience providing survey solutions in Taiwan, we offer these services to energy developers and owners to provide a detailed insight into seabed and structural 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.
Foundation and Scour condition monitoring and volume calculations are performed using ultra-high resolution 3D visual surveys around WTG foundations. This can identify such maintenance issues as anode depletion, structural integrity concerns, cable protection system movement and bend radius compliance, as well as highlighting where tidal currents have removed material which might compromise the security of foundations or exposed cables. 3D images, maps and volumetric calculations of material moved are produced and the use of ROVCO technology in capturing this data in real time allows actionable data to be gathered and rectification decisions taken ashore, resulting in more efficient campaigns.
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.
Cable crossing condition, CPS protection monitoring and depth of burial verification surveys using ROV based tools such as TSS 660, Innovatum Smartrak or the Pangeo 3D Seismic system. Additionally, we cooperate with ROVCO, the world’s leading provider of ROV and hydrographic surveys, to provide optimised state of the art live 3D vision technology to acquire accurate and high quality data. Utilising AI trend analysis, we can identify likely faults on subsea structures, as well as within the internal environment of the monopile.
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.