The Fundy Ocean Research Center for Energy (FORCE) is a leading research centre for in-stream tidal energy technology. Located at Minas Passage in the Bay of Fundy, the currents can exceed 6 m/s (Oceans Ltd., 2009), making it ideal for testing in-stream technology in harsh environments. The effect of turbine noise on marine life is recognised as a potential environmental impact of in-stream turbines that must be understood (Polagye et al., 2011). It is expected that the rotating mechanical equipment in tidal turbines will emit continuous tones into the water, potentially at levels that may harm or harass marine life (Polagye et al. 2011; Stein, 2011). The differences between the soundscapes with and without the turbine in place must be measured to assess impact. Ideally recordings should be made in all seasons, weather and tidal states and flow noise in the data must be minimised. FORCE made drift measurements of the sound levels at Minas Passage in 2008 and 2009 before and after the installation of an Open Hydro turbine, however, the results were deemed not reliable due to vessel and surface noise issues and the short term nature of drifting measurements (Schillinger, 2010). In 2011 JASCO began a project to demonstrate long-term measurements of ambient and turbine noise at FORCE using a special purpose high-flow mooring (HFM) previously developed for measurements in Bristol Channel. The extreme conditions at Minas Passage make deployments and retrievals challenging. The initial deployment was called off when shock loading severed the anchor block on the acoustic releases. Both moorings in the second deployment were lost. Detailed hydrodynamic modelling and discussions with mooring experts were conducted before the third deployment in March 2012. The HFM and a more traditional stream-lined buoy design were deployed and recovered. The data show that the high-flow mooring provides usable measurements in all tidal states.
Measurement of Long-Term Ambient Noise and Tidal Turbine Levels in the Bay of Fundy
Title: Measurement of Long-Term Ambient Noise and Tidal Turbine Levels in the Bay of Fundy
November 23, 2012
Conference Name: Acoustics 2012
Conference Location: Fremantle, Australia
Publisher: Australian Acoustical Society
Martin, B.; Whitt, C.; McPherson, C.; Gerber, A.; Scotney, M. (2012). Measurement of Long-Term Ambient Noise and Tidal Turbine Levels in the Bay of Fundy. Paper Presented at the Acoustics 2012, Fremantle, Australia.