kennedy environmental limited - aucklandcouncil.govt.nz · 173 db sel cum(hf) phocid pinnipeds (pw)...

Kennedy Environmental Limited

Further Information 14 June 2018

America’s Cup Wynyard Hobson 1

14 June 2018

Attn: Nicola Broadbent (Team Leader)

Auckland Council

CC/ Alan Moore (Principal Specialist- Coastal); and

Tracey Grant (Principal Project Lead- Premium Resource Consents)

By Email: [email protected], [email protected],

[email protected]

Dear Nicola,

Further Information provided in relation to America’s Cup Wynyard Hobson BUN60318372

During the week ending 10 June 2018 we held several meetings with Auckland Councils acoustic specialists

Jon Styles and Matt Pine (Styles Group who are reviewing the Marshall Day construction noise and

vibration assessment1 submitted in support of the application (13 April 2018).

Through Styles Groups assessment a number of typographical errors were identified in our specialist report

(at Sections 5.3.2 and 5.3.3) which Mr Fitzgerald (Marshall Day) provides clarifications of below.

Mr Pine and Mr Styles also requested information on the extent of the 120 dB re. 1 µPa rms underwater

noise contour for vibratory driven piles, retraction of the third paragraph in Section 4.3.4 of the

construction report referring to a threshold of 150 dB re. 1 µPa rms, and removal of the behavioural

response contours from Figures 6 and 7. Mr Fitzgerald has considered this request and we provide a

response below. Additional information has been provided by Mr Paul Kennedy (Kennedy Environmental

Limited) in relation to mammals present and potential effects.

Typographical Errors

Section 5.3.2: Table 11 is attached. The SELcum (mf) and SELcum (pw) values for impact driven 900mm steel piles

in the top row were 15 decibels too high, reflecting a source level at a receiver distance of 1m rather than

10m. This error does not affect the modelling inputs, results and conclusions of the assessment.

Section 5.3.3: Bullet point 2 refers to “impact driven concrete piles2”. This should refer to “impact driven

steel piles3 and vibro driven steel piles4” to reflect the proposed activities assessed. Again, this error does

not affect the modelling inputs, results and conclusions of the assessment.

1 Rp 005 r08 20171213 CMF (AC Wynyard Hobson Construction Noise and Vibration Assessment) 2 California Department of Transportation: ‘Technical Guidance for Assessment and Mitigation of the Hydroacoustic Effects of Pile Driving on Fish’ (Nov 2015), Figure I.7-5 3 ITAP –Institut für technische und angewandte Physik GmbH: ‘Ermittlung der Schalldruck-Spitzenpegel aus Messungen der Unterwassergeräusche von Offshore-WEA und Offshore- Rammarbeiten’ (2005) 4 ITAP –Institut für technische und angewandte Physik GmbH: ‘Spektren der Vibrationsramme beim Umspannwerk’ (2011)

mailto:[email protected]






Marine Mammals – Acoustic Thresholds

Section 4.3.4 of the Marshall Day Acoustics report provides guidance on thresholds that may invoke

behavioural response from marine mammals from the US Department of Commerce National Oceanic and

Atmospheric Administration (referred to as the ‘NOAA Guidelines’). NOAA states that behavioural impacts

can occur at levels as low as 120 dB re. 1 µPa rms for vibratory driven piles depending on the noise

environment.

The third paragraph of Section 4.3.4 suggests a higher threshold, taking into account the high noise

environment. We consider identifying that the 120 dB re. 1 µPa rms extents would enable a more

precautionary assessment of effects by a marine ecologist (refer below) and replaces this paragraph. The

behavioural response contours have also been removed from Figures 6 and 7 and the updated versions

are attached to this letter.

It was understood at the meeting held on the 08 June 2018 that this is not material to the conclusions of

the assessment (as discussed in the marine ecology noted below) and is not relied upon by the Construction

Noise and Vibration Management Plan.

Mr Styles requested that the extent of the 120 dB re. 1 µPa rms contour be established in order to reflect

the more precautionary extent of effects which could potentially result. We advise that this contour is

predicted to extend up to 6km from the works area, based on the use of a 900mm diameter steel pile

during vibratory pile driving. Geographically, the zone extends westwards towards the Harbour Bridge and

eastwards towards the heads of the Waitemata Harbour, indicatively bounded by North Head, Bean Rock

lighthouse and Bastion Point.

Marine Mammals, Responses to Piling Noise

The changes in acoustic environment were considered in relation to the key groups of marine mammals

known to enter the Waitemata Harbour. As described in Golder (2018) these are typically fur seal (an

otariid pinniped), leopard seals (a phocid pinniped (true seals) – have an extended frequency range

compared to the other otariid seals), bottle-nose and common dolphins and orca (mid-frequency

cetaceans). In addition, larger cetaceans such as the southern right whale (a baleen whale -low frequency

cetacean) are occasionally seen in the lower harbour. Updated versions of Tables 7, 10 and 11 of the

Marshall Day Acoustics report are attached to include the addition of fur seal (otariid pinnipeds) to the

species of interest.

The NOAA guidance provides guidance in relation to Permanent Threshold Shifts (PTS) and temporary

threshold shifts (TTS) Onset for both impulse and non-impulse sounds. The thresholds are summarised in

Table 7 attached. These thresholds occur very close to the piling source and as such any marine mammals

present in the lower harbour will not be exposed to such close proximity effects. NOAA also provides

interim sound threshold guidance for behavioural impacts. Behavioural sound thresholds are a level at

which a variety of disturbances to normal marine mammal activity might occur (these include feeding,

breathing, nursing, interruption to vocalisation). It is likely that the simplest response that piling noise may

result in is changing direction to move away from the source. The guidance is 120 dB re. 1 µPa rms for

continuous sources (vibratory piling) and 160 dB re. 1 µPa rms for impulsive sources. The latter would be

limited to a restricted area of Freemans Bay. The continuous source guidance would include a wider area

of the lower Waitemata Harbour (but would not extend out of the harbour).

There are no permanent marine mammal residents within the Waitemata Harbour. The leopard seal is the

only species that is ‘resident’ as there is a single or at times two individual seals that can be present within

the Harbour at times. The seal is often identified in Westhaven Marina but can be seen up the Harbour to




Hobsonville and down to Torpedo Bay. The seals may habituate to some noise while in the harbour for

extended periods. Fur seals are seen in the harbour including around the Harbour Bridge. Both bottle-

nose, common dolphin and orca are harbour visitors and will travel up harbour at times. The frequency

(e.g., through sightings) is not known but for the purpose of the assessment this has been assumed to be

occasional based on limited observational data (including the Department of Conservation sighting

database). Overall, marine mammals in the identified groups would be exposed to behavioural adjusting

sound if entering the lower harbour during periods of continuous piling. These marine mammals would

be exposed to other noise sources especially vessel related noise when entering the harbour on most

occasions which are likely to illicit behavioural responses of varying degrees depending on source. We

would note one recent long-term study of piling noise on bottlenose dolphins and harbour porpoises in

the Cromarty Firth (Scotland) an area with shipping and other noise (Graham et al. 20175). The study

showed that significant displacement responses during piling activity (observed elsewhere) may not always

occur. Bottlenose dolphins spent a reduced period of time in the vicinity of construction works during both

impact and vibration piling in study location.

Overall, any effects should they occur will be of a behavioural nature and are likely to affect dolphins and

orca entering the lower harbour. Management of piling work will assist in minimising any adverse effects

should any mammals be identified as potentially entering Freemans Bay.

We trust this information is satisfactory. If you have any further questions please do not hesitate to contact

us.

Yours faithfully

Craig Fitzgerald

Associate

Paul Kennedy

Unio Environmental MARSHALL DAY ACOUSTICS

LIMITED

Kennedy Environmental

5 Graham IM, Pirotta E, Merchant ND, Farcas A, Barton TR, Cheney B, Hastie GD, Thompson PM 2017. Responses of bottlenose dolphins and harbor porpoises to impact and vibration piling noise during harbor construction. Ecosphere 8(5):e01793. 10.1002/ecs2.1793.




ATTACHMENTS:

Table 7: Summary of NOAA TTS and PTS thresholds6

Species Threshold Type Impulsive sources

(e.g. impact piling)

Non-impulsive sources

(e.g. vibro piling)

Low-Frequency Cetaceans (lf) TTS 213 dB Lpeak

168 dB SELcum (lf)

179 dB SELcum(lf)

PTS 219 dB Lpeak

183 dB SELcum (lf)

199 dB SELcum(lf)

Mid-Frequency Cetaceans (mf) TTS 224 dB Lpeak

170 dB SELcum (mf)

178 dB SELcum(mf)

PTS 230 dB Lpeak

185 dB SELcum (mf)

198 dB SELcum(mf)

High-Frequency Cetaceans (hf) TTS 196 dB Lpeak

140 dB SELcum (hf)

153 dB SELcum(hf)

PTS 202 dB Lpeak

155 dB SELcum (hf)

173 dB SELcum(hf)

Phocid Pinnipeds (pw) TTS 212 dB Lpeak

170 dB SELcum (pw)

181 dB SELcum(pw)

PTS 218 dB Lpeak

185 dB SELcum (pw)

201 dB SELcum(pw)

Otariid Pinnipeds (ow) TTS 226 dB Lpeak

188 dB SELcum (ow)

199 dB SELcum(ow)

PTS 232 dB Lpeak

203 dB SELcum (ow)

219 dB SELcum(ow)

6 SEL thresholds have a reference of 1 µPa2s and Lpeak thresholds have a reference of 1 µPa




Table 10: Pile Driving underwater source levels

Size and method Source levels (dB re 1μPa at 10m)

Details Peak RMS SELSS SELcum (mf) SELcum (pw) SELcum (ow)

Impact driven 900mm steel 900 strikes/day7 200 183 173 184 196 196

Vibro driven 900mm steel 3 hours driving/day8 180 170 N/A 192 201 202

7 3 piles per day at 300 strikes per pile (refer Section 2.0) 8 3 piles per day at 60 minutes per pile (refer Section 2.0)




Table 11: Zones of influence (additions represented in bold)

Species Threshold Impact piling zone

(900mm steel)

Vibro piling zone

(900mm steel)

All species PTS – peak Below criteria Below criteria

TTS – peak Below criteria Below criteria

Behavioural response 560m 6000m

Phocid pinnipeds (pw) PTS – cumulative exposure 140m 45m

TTS – cumulative exposure 770m 450m

Mid-frequency cetaceans (mf) PTS – cumulative exposure 30m Below criteria


Otariid pinnipeds (ow) PTS – cumulative exposure 10m Below criteria


Sourced from the LINZ Data Service and licensed for re-use under the Creative Commons Attribution 3.0 New Zealand licence

0 25 50 75 10012.5

Meters

Folder I:\JOBS\2017\20171213\06 Drawings\America's Cup GIS\

Scale @ A3: 1:3,000Prepared by: BLDate: 14/06/2018

AC36 - Underwater Management ZonesFigure 6: Wynyard Impact Piling

Noise Sources

Piling

PTS

Mid-Frequency Cetaceans

Otariid Pinnipeds (<10m)

Phocid Pinnipeds

TTS


Otariid Pinnipeds

Phocid Pinnipeds

Sourced from the LINZ Data Service and licensed for re-use under the Creative Commons Attribution 3.0 New Zealand licence

0 25 50 75 10012.5

Meters

Folder I:\JOBS\2017\20171213\06 Drawings\America's Cup GIS\

Scale @ A3: 1:3,000Prepared by: BLDate: 14/06/2018

AC36 - Underwater Management ZonesFigure 7: Wynyard Vibro Piling

Noise Sources

Piling

PTS

Mid-Frequency Cetaceans (below criteria)

Otariid Pinnipeds (<10m)

Phocid Pinnipeds

TTS


Otariid Pinnipeds

Phocid Pinnipeds

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