Analyzing the Temporal Patterns Associated with the Installation of Monopile Turbines thru Pile-Driving at Vineyard Wind 1, Massachusetts

Abstract

Offshore wind is seen as a means to boost renewable energy production and decarbonize the power sector. However, there is apprehension to adopt offshore wind as its effect on marine life is still unknown. Pile-driving, an impulsive, repetitive, low-frequency sound, during the construction phase of offshore wind can emit noise in the same frequency that baleen whales communicate. Previous studies on low-frequency seismic activity show calling rates and sightings decreased during activity. For this study, we used acoustic data to characterize temporal patterns from pile-driving of Vineyard 1 and sound exposure level changes. On average, pile-driving had the following: 3268 strikes per piling event, inter-pulse of 1.47 s, time interval between pile-driving periods of 111.41 s, exposure duration of 1.89 hrs, strike rate of 1792.2 strikes/hr, pulse duration of 0.60 s, and duty cycle of 29.7%. On average, the mean difference between the nearest and furthest recording unit from pile-driving found an increase in average pulse duration by 6.4%, an increase in inter-pulse duration of 0.1%, an increase in duty cycle of 6.4% and decrease in SEL by 8.3 dB. Key recommendations include:

Long-term monitoring and studies are needed that examine how pile-driving events impact baleen whale behavior and hearing The inclusion of temporal analysis resulting from pile-driving events in future studies