Hydroschall – underwater noise emissions

In the construction of offshore structures like offshore wind farms, oil drilling platforms, research platforms and others, foundations are poured, steel piles are driven into the seabed or drilling takes place all causing significant underwater noise emissions. In marine mammals, especially harbour porpoises, short or longer exposure to considerable noise levels may lead to temporary or even permanent hearing loss.

The first joint project for offshore wind farm Borkum West II and the follow-up project during the construction of GlobalTech I therefore aimed to find ways to reduce underwater noise emissions during pile driving. For this purpose, a big bubble curtain (BBC) has been developed and tested and further optimised in the follow-up project. During the construction of Borkum West II, acoustic measurements and behavioural observations of harbour porpoises were used to assess the effectiveness of the reduction of noise emissions. During the construction of offshore wind farm GlobalTech I, the big bubble curtain was further developed, deployed in deeper water and became a routine part of the offshore installation process.

The animated video about the big bubble curtain provides a good overview of the technology.

BioConsult SH is collaborating on this project with the following partners: the companies Hydrotechnik Lübeck GmbH and itap GmbH, Oldenburg as well as the Institute of Structural Analysis at Leibniz University Hannover. Part of the analyses was performed at the Centre for Research into Ecological & Environmental Modelling of the University of St. Andrews.