1. An Overview of Pile Driving Effects on Fish For the: Oregon Department of Transportation By: Robert R. Abbott, Ph. D. May14, 2009

2. Presentation Overview  How did we get here?  Why Pile Driving Impacts Fish  Introduction to Underwater Sound  The California Experience

3. At the Pile Installation Demonstration Project for the Bay Bridge in San Francisco Bay, NOAA noted birds and dead fish.

4. Gulls Quickly Flocked to the Area

5. A Typical Gull Pattern

6. Occasionally There Were Very Large Flocks (> 500 gulls)

7. Benicia-Martinez Bridge killed many fish including salmon and sturgeon, and resulted in millions of dollars of compensatory mitigation. “We are too busy building American to be concerned about this****”

8. What Is The Big Deal about a few dead fish?  Fish floating up to the surface are now noticed  Dead fish get advocacy groups involved  Some are threatened and endangered species  Some fish are recreationally important  Some fish are commercially important  Lots of dead fish: bad media attention

9. Richmond-San Rafael Bridge. There was no mitigation on this project and it also resulted in millions of dollars of compensatory mitigation.

10. San Francisco Bay Area Studies  Piscivorous bird studies  Hydroacoustic monitoring of fish schools  Fish salvage  Necropsies  Caged fish studies  Behavioral Studies

11. Berth 22 for Port of Oakland

12. Cushion Block

13. Concrete Piles

14. Pile Installation Demonstration Project

15. How underwater sound affect fish?  Temporary -hearing threshold shift  Startle response  Compression and expansion of swim bladder  Kidney damage  Injury to the inner ear hair cells  Ruptured capillaries  Ruptured heart

16. Air pockets in fish  Swimbladder – Physostomous - salmonids, sturgeon – Physoclistous - Carp, perch, rockfish  Air pockets leading to the ear  Micro air bubbles in tissues and capillaries  Intestinal gas

18. Inner Ear of Fish

19. Piscivorous Bird Studies  Circling, diving  Some coming up with a fish  Many big fish recover and swim away  Only gulls, no other species  No birds injured to date

20. Competition with Gulls

21. Fish Salvage Taught Us:  Only swim bladder fish  No sharks or flat fish  Tough to beat the gull at collecting fish  Most small fish never surface  All sizes killed  Easy pickings for predators below

22. Hydroacoustic Monitoring of Fish Schools  They do not move away  Small fish appear to be entrained  Some species attracted to physical structures  Some species may actually be attracted to vibrations in the water

23. Why Don’t They Move Away?  Some probably do  Some can not tell which way to go  Some can not get out of the way even if they can tell which way the sound is coming form  Some are attracted  Some not adversely affected

24. Necropsies: External Indications  Red eye  Red belly  Protruding organs  Red fins  Scale loss along the abdomen

25. Traces of Blood in the Eye

26. Loss of Scales Along the Abdomen

27. Slight reddening around the belly

28. Red Head

29. Rupture of the Body Cavity

30. Protruding Internal Organs

31. Necropsies: Internal Indications  Internal bleeding  Ruptured swim bladder  Ruptured heart chambers  Smashed kidney  Pulverized internal organs

32. Massive Internal Bleeding

33. Ruptured Swim Bladder

34. Hole in the Posterior Swim Bladder

35. Rupture of the Kidney

36. Behavioral Observations  Short term erratic swimming pattern  Whirling behavior  Startle response  Twitch response  Delayed mortality

37. Zone of Impact  Near-term mortality zone  Delayed mortality zone  Non-lethal effects on behavior Adverse effect on hearing May affect fish migration routs May affect spawning success Reduce survival rate

38. Pile Near-term Mortality Zone Delayed Mortality Zone Zones of Impact

39. Introduction to Underwater Noise  Frequency  Wave form  Amplitude  Pulse  Peak Sound Pressure Level & RMS  Energy flux density  Shallow water distortion

40. Frequency Characterization

41. Frequency: Pile Impulse Histogram  Most energy is below 1 KHz  Low frequency = long wave length  Propagate a long distance

42. Bubble Curtain Off @ 30 m Peak Pressure = 209 dB or 28 kPa

43. 30m Bubble Curtain ON Peak Pressure = 198 dB or 8 kPa

44. Wave Form  Under pressure spike  Time in ms to peak under-pressure  Time in ms to peak over-pressure

45. Rate of propagation loss

46. Amplitude Measurements  Measured in terms of dB re 1 µ Pa  Peak and RMS  Measured at a reference distance  At least two meters below the surface  Not the same as measuring sound in air  Very few experts around

47. Pulse Pulse Pulse Pulse  Relatively long impulse  Repetition for hours  Cumulative effect

48. Shallow Water Distortion  Accelerated rate of attenuation  Pressure relief at the surface  Reflection off the surface  Reflection off the bottom  Standing waves  Doppler effects due to tidal currents  Wave guide phenomena

49. Mitigation Strategies  Bubble curtains  Fabric barriers  Isolation casings  Construction windows  Fish distribution monitoring  Compensatory mitigation

50. LET THERE BE LOTS OF BUBBLES

51. Bubble Curtain Schematic

52. Key Concepts in Bubble Curtain Technology  Metric is bubble flux density  Decouple pile from water  The closer the better  Filter out higher frequencies  Reduce amplitude from 6-30 dB  Increase rise time to peak  Delays arrival of peak

53. PRESSURE WAVE PILE BUBBLE CURTAIN EXPANSION WAVES HEAT RADIATION DISTORTED PRESSURE WAVE How Bubble Curtains Work

54. Primary Feed Lines

55. PRIMARY DISTRIBUTION LINES

56. ON DECK MONITORING Digital flow meters and analog gauges to monitor air flow rate and distribution

57. Bubble Curtain Deployment Pile driving operations at Pier E6E. Water depth is 26 feet.

58. Bubble Curtain On

59. Bubble Curtain off

60. Placing the hydrophone in the cage

61. Hydroacoustic monitoring equipment

62. Placing fish in a cage

63. Post exposure observations

64. Loading fish onto the research vessel

65. Up to 10 batches of fish

67. Retrieving the cage while keeping the fish in water at all times

68. ACKNOWLEDGEMENTS  Manson Construction  Caltrans: District 4  Illingworth and Rodkin  Charles Greene  Art Popper  Glenn Fleming  Robert Blizard