Fugro will start a geophysical survey in and around the 586MW Gwynt y Môr offshore wind farm in early April, a notice to mariners reveals.
The survey will start on 4 April, weather permitting, and will last for up to one week.
During that time, a 42-metre survey vessel MV Meridian will carry out both bathymetric and sidescan sonar surveys at the site.
The vessel will be mobilising from Liverpool and will operate on a 24 hour basis.
Gwynt y Môr is the world’s second largest operating offshore wind farm, located off the North Wales coast.
Fully commissioned in June 2015, the 576MW project comprises 160 Siemens 3.6MW turbines.
The wind farm is a GBP 2 billion partnership between innogy, Stadtwerke München GmbH, and Siemens.