Abstract
This study presents comprehensive underwater noise recordings collected from first offshore installation of large monopile foundations using a novel low-noise jetting technology in Ørsted’s German project Gode Wind 3. Variability of the measured sound levels is assessed across different installation locations, distances from the foundation and phases of the installa tion. Measurements are analysed against standard acoustic metrics such as peak pressure level, sound pressure level and cumulative sound exposure level. Additionally, the measurements are compared against typical previously measured acoustic emissions from impact piling. Both sets of data are integrated with a sound propagation model to derive corresponding sound source levels and simulate propagation to extended distances. The results are subsequently discussed in the context of various underwater noise regulations from different markets. It is demonstrated how the low-noise jetting technology produces significantly lower sound levels by more than 30 dB. Consequently, this also yields lower distances to environmental thresholds.