There is a ‘window of opportunity’ to get the monopiles into the Rampion wind farm presently under construction off the UK’s Sussex coast: the piling has to stop in November for the herring spawning season.
But despite the challenges it’s going well: by the end of the first week in September, MPI Discovery had installed 44 foundations while Pacific Orca had clocked up 24: the transition pieces are being installed on top straight away which helps keep the piles – not high above the water in themselves - visible. Apart from picking up three or four of the piles from the discharge port at Vlissingen (each of the lengths being tailored for the depths and seabed spot) the vessels tend to alternate the installation work.
All in all, over 70 of the total 116 foundations have now been installed – although it has to be mentioned that for a few days, the sound of the piling has been an issue for the residents in Shoreham, UK.
E.On admitted that “weather, background ambient noise level, the size of the pile and nature of the seabed” made a difference to how the sound carried and promised to monitor the situation – occasionally keeping piling work out of unsociable hours, but added that it was “not an exact science”.
However recently MV Erica has been trailing hydrophones to monitor underwater noise... not so much for the onshore population, but for those in the sea.
The surveyors onboard the monitoring vessels listening in through the hydrophones for the telltale clicks that would alert the crew to marine mammals within the 600m diameter marine mammal mitigation zone, and only if it’s clear will the piling commence.
Certainly some of the crew have been impressed by the care taken: “Despite the fact there’s a lot of money involved, this wind farm is environmentally friendly, it’s not just about ‘green’ power, it is in the construction phase too,” commented one.