Work will begin this week at the Rampion Offshore Wind Farm along the Sussex coast, E.ON has announced.
The work is taking place in preparation for the first foundation installation in January.
It will include clearing boulders on the seabed along the cable route and around each of the 116 foundation positions to allow safe and effective installation.
This phase of the project coincides with work commencing onshore, with the first of 12 stages of the onshore project which started in early September.
Access points will be developed first to allow construction of a haul road along the cable route. Trenching works will then follow to lay the ducting for the cables, and eventually the reinstatement of the ground.
Work will start on building the onshore substation in Twineham towards the end of September.
Chris Tomlinson, E.ON Development Manager for the Rampion Offshore Wind Farm, said: "After five years in development, following successful consultation, consent and contracting, we're delighted to be able to confirm that work will commence this week to prepare the seabed for turbine installation.
"Assessment of the number of boulders is still underway but is likely to be in the thousands and up to six vessels will be on site to undertake the work over the next many months. Great efforts will be made to replicate the seabed as it is now and all boulders moved will be weighed and the new position recorded."
The 400MW 116 turbine project being built by E.ON and the UK Green Investment Bank will, when complete, provide enough electricity to supply the equivalent of around 300,000 homes.
(LM)
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