Seiche Keeps Marine Mammals from Harms Way During Offshore WInd Farm Construction

November 5, 2020

Credit: Ørsted

Worlds largest offshore wind development company Ørsted has awarded Seiche a contract to ensure marine mammal safety during the construction of the Hornsea Two offshore wind farm in the UK.

Seiche, which provides marine technology and environmental service solutions for the offshore marine industries, has deployed specialist team of personnel and equipment to two key vessels on Ørsted’s Hornsea Two offshore wind farm site. 

Their purpose is to manage Ørsted’s commitment to ensure impacts to marine mammals during the Hornsea Two wind farm construction activities are negligible.

Specializing in marine mammal monitoring and mitigation measures, the team from Seiche has been brought on board to ensure compliance with procedures that seek to minimize the effects of construction noise on the local marine population. Key species known to occur in the project area are harbor porpoise, white-beaked dolphins, minke whales as well as grey and harbor seals, Seiche said.

Prior to any construction activities taking place, dedicated Marine Mammal Observers (MMOs) will monitor the area for any animals that could be affected by the noise produced from pile driving.

Monitoring activities are taking place from DEME’s jack-up installation vessels during the installation of 165 monopiles as well as Heerema’s semisubmersible crane vessel Sleipnir during the construction of the 2 offshore substations. 

In addition to visual monitoring to ensure marine mammals are not within close proximity to piling operations, acoustic deterrent devices (ADDs) are used to deter animals from the area to protect them from harmful levels of noise.

Should a mammal be detected within the designated protection zone piling operations are delayed until the mammal leaves the area.

In total, 165 monopiles and transition pieces will be installed at sea in preparation for the site’s 8.4 MW turbines. Ørsted’s Hornsea Two wind farm, located approximately 89km off the Yorkshire coast in the North Sea, will surpass its predecessor Hornsea One by generating 1.4 GW of electricity once complete in 2022.