Environmental assessment of offshore wind power generation: effect on a noise budget.

The construction, operation, and removal of offshore wind power facilities have the potential to increase the levels of noise in the surrounding waters. Increased shipping noise can be associated with all phases of the life cycle of wind farms. Pile driving during platform construction can be short-lived but can introduce very high intensity pulses into the ocean. Operational noise, while at a much lower level, can affect the surrounding area almost continuously for the life of the facility. The removal of wind platforms at the end of their operational life may use explosives, again shortlived but very intense. In August 2008, the state of Rhode Island began planning for offshore renewable energy development with the establishment of a Special Area Management Plan (SAMP) for the ocean just south of Rhode Island. SAMPs are federally recognized management and regulatory tools that promote ecosystem-based management as well as reasonable coastal-dependent economic activity. The Ocean SAMP is an adaptive planning tool that promotes a balanced and comprehensive ecosystembased management approach to the development and protection of Rhode Island’s ocean-based resources, specifically offshore renewable energy. Part of the Ocean SAMP involves research into the potential effects of noise from construction, operation, and removal of offshore wind power facilities on marine animals. This paper concentrates on the low-level but almost continuous ocean noise from the operation of offshore wind turbines. The effects of this low-level operational noise on the marine environment may be subtle and difficult to observe without detailed measurements. European investigators have measured underwater noise from offshore wind turbines for different wind speeds and power production levels. Betke et al. ( 2004 ) found noise levels averaging 112 dB re 1 m Pa in a one-third octave band centered near 200 Hz at a distance of 110 m from a wind turbine Environmental Assessment of Offshore Wind Power Generation: Effect on a Noise Budget