Geotechnical Campaign for offshore wind farm in Noirmoutier

The Client, the company Eoliennes en Mer Iles d’Yeu et de Noirmoutier has performed a geotechnical campaign on the Iles d’Yeu et de Noirmoutier Offshore Wind Farm in France. The geotechnical campaign consisted of 64 boreholes with depths of 35 to 50 m below sea level and has taken place in 2017 (29 boreholes) and 2018 (35 boreholes).  IMDC was contracted to perform the follow-up and interpretation of the offshore geotechnical campaign including onshore laboratory testing.

The project area is located close to Iles d’Yeu et de Noirmoutier, at approximately 20 km of the mainland of France. The Client is planning to construct 62 wind turbine generators (WTG) and an offshore high voltage substation (OHVS). The soil in the project area consists of an alteration of sand and dolomitic rock layers. 

IMDC has provided the following services to the Client during the geotechnical campaign: 

  • Review of HSSE documentation prior to mobilisation
  • Client Representative during offshore geotechnical survey
  • Client Representative during onshore laboratory testing program
  • Interpretative report. 

The interpretative report of the geotechnical campaign will be used as site book for the designers of the foundations of the WTG and OHVS and of the inter-array cables.

Sample preparation for mechanical rock testing (UCS)

Recovery of sand sample during the offshore site investigation


  • Client: Eoliennes en Mer Iles d'Yeu et de Noirmoutier
  • Start date: 2017
  • Completion date: 2018