Difference between revisions of "Ship quieting technology"

Revision as of 23:23, 20 October 2008

Information about technologies that have been proven to reduce underwater noise in ships and boats. The emphasis here should be on practical solutions that make economic sense to boat owners.

Thanks to Brandon Southall of NOAA for coordinating the conferences on this subject and for distilling much of these data and resources! As I wrote to him, "It would be *great* if there were some case studies that include cost/benefit analysis of particular quieting technologies (including practical manufacturer-model-number-type specifics)." Let's try to focus on such information here.

Motivation

• Endangered southern resident killer whales use sound for communication and foraging
• Ships and boats dominate the noise budget within killer whale critical habitat
• It is relatively feasible to mitigate the risk of acoustic impacts (compared with risks due to salmon depletion and persistent pollutants)
  • Recreational retrofits are possible
  • Commercial whale watching vessels could be quieted
  • WA State ferries are being replaced
  • Commercial ships transit critical habitat ~20 times/day

International workshops and agreements

• IMO request (June, 2008) Request to add ocean noise mitigation to IMO Marine Environment Protection Committee.
• Report from Hamburg Workshop (April 21-24, 2008) "International Workshop on Shipping Noise and Marine Mammals"
• International Symposia on "Potential Application of Vessel-Quieting Technology on Large Commercial Vessels"
  • May 1-2, 2007 (MD) web site | talks
  • October 19-21, 2005 (TX) 2005 Outreach Event Large Vessel Acoustics Outreach/Information Exchange
  • May 18-19, 2004 (VA) web site | report

Ships (large vessels)

• Ship noise underwater in Haro Strait (Veirs and Veirs, 2006, ASA presentation; PPT | PPT zip (w/sound files)
• Cost/benefit ideas for commercial ships (Wittekind, 2007, from 2007 Symposium site)
• Veth Z-drive (mentions sound level, but no measurements provided)

Boats (small vessels)

• Whale watch noise in Haro Strait (Hildebrand et al., 2006)
• Sounds from whale watching vessels (Tim Hunt; fall, 2007) "Investigating high frequency underwater boat noise and potential masking of killer whale echolocation clicks"
• Ducted propeller systems are being tested and patented by Marine Propulsion Technologies in CA (no noise reduction results as of 10/2008)