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WESTHAVEN MARINA EXTENSION ACOUSTIC ASSESSMENT

Rp 001 20170963 | 22 December 2017

http://www.marshallday.com

84 Symonds Street

PO Box 5811 Wellesley Street

Auckland 1141 New Zealand

T: +64 9 379 7822 F: +64 9 309 3540

www.marshallday.com

Project: WESTHAVEN MARINA EXTENSION

Prepared for: Panuku Development Auckland PO Box 90343 Victoria Street West Auckland 1010

Attention: Phil Wardale

Report No.: Rp 001 20170963

Disclaimer

Reports produced by Marshall Day Acoustics Limited are based on a specific scope, conditions and limitations, as agreed between Marshall Day Acoustics and the Client. Information and/or report(s) prepared by Marshall Day Acoustics may not be suitable for uses other than the specific project. No parties other than the Client should use any information and/or report(s) without first conferring with Marshall Day Acoustics.

The advice given herein is for acoustic purposes only. Relevant authorities and experts should be consulted with regard to compliance with regulations or requirements governing areas other than acoustics.

Copyright

The concepts and information contained in this document are the property of Marshall Day Acoustics Limited. Use or copying of this document in whole or in part without the written permission of Marshall Day Acoustics constitutes an infringement of copyright. Information shall not be assigned to a third party without prior consent.

Document control

Status: Rev: Comments Date: Author: Reviewer:

Issued - For Resource Consent 22 Dec 2017 Ben Lawrence Craig Fitzgerald


This document may not be reproduced in full or in part without the written consent of Marshall Day Acoustics Limited

Rp 001 20170963 BL (Westhaven Marina Extension - Acoustic Assessment).docx 3

1.0 INTRODUCTION .................................................................................. 4

2.0 PROJECT DESCRIPTION ....................................................................... 4

3.0 PERFORMANCE STANDARDS ............................................................. 4

3.1 Operational Noise ............................................................................... 4

3.2 Construction Noise (Airborne) ........................................................... 4

3.3 Construction Noise (Underwater) ..................................................... 5

4.0 EXISTING ENVIRONMENT .................................................................. 6

4.1 Overview ............................................................................................. 6

4.2 Airborne Noise .................................................................................... 6

4.3 Underwater Noise .............................................................................. 6

5.0 CONSTRUCTION ASSESSMENT .......................................................... 7

5.1 Methodology....................................................................................... 7

5.2 Airborne Noise .................................................................................... 7

5.3 Underwater Noise .............................................................................. 8

5.4 Underwater Noise from Dredging ..................................................... 8

5.5 Construction Noise Management ................................................... 10

6.0 OPERATIONAL NOISE ....................................................................... 10

7.0 CONDITIONS OF CONSENT .............................................................. 10

8.0 CONCLUSIONS ................................................................................... 10

APPENDIX A GLOSSARY OF TERMS

APPENDIX B AUP OIP PLANNING MAP

APPENDIX C HYDROPHONE AND RIGGING DETAILS

TABLE OF CONTENTS




1.0 INTRODUCTION

Marshall Day Acoustics (MDA) has been engaged by Panuku Developments Auckland to undertake an assessment of acoustic effects for the proposed extension to the Westhaven Marina breakwater and causeway.

This report assesses potential airborne and underwater noise associated with the construction and ongoing operation of the marina. The proposed activities are assessed against the relevant legislation, planning rules and existing environment.

Vibration has not been addressed in detail because it is predicted to be negligible, and generally not perceptible, at nearby sensitive receivers during the construction and operation of the facility.

A glossary of acoustic terminology is included in Appendix A.

2.0 PROJECT DESCRIPTION

The proposal includes an extension of the north-western breakwater and causeway (via reclamation) to connect to the north-eastern breakwater (refer Figure 1 and Figure 2), as well as conversion of many existing moorings into new accessible berths. The project is to provide:

• Approximately 6,300m2 of new reclamation:

o 60% will be hardstand used for access ways and 103 additional car parks

o 40% will be used for cultural elements, landscaping and open space

• 117 new marina berths

The reclamation is proposed to be constructed from mudcrete (a mixture of concrete and material dredged from a barge). New berths and promenade piles will likely be drilled, but allowance for vibro and impact piling methods is necessary. The piles are proposed to be either timber or concrete with steel casings.

The site is bordered by harbour to the north and east, and the northern motorway (SH1) to the south and west. The St Marys Bay residential area is located approximately 600 – 700m south of the site. The Wynyard Quarter business district is located a similar setback to the east.

Figure 1: Aerial Map of Project

Figure 2: Artists Representation of Project

3.0 PERFORMANCE STANDARDS

3.1 Operational Noise

Under the Auckland Unitary Plan Operative in Part (AUP OIP), Westhaven Marina is located in the Coastal – Marina Zone (refer Appendix B for planning map). Land to the south is zoned Residential, and to the east is zoned Business.

Auckland Unitary Plan Operative in Part (AUP OIP) rule E25.6.11 requires that activities in the Coastal – Marina Zone must not exceed 60 dB LAeq at all times within the boundary of any other site in this zone.

AUP OIP rule E25.6.20 requires that activities on land in the Coastal – Marina Zone must not exceed the following noise limit within a residential zone:

• Monday to Saturday, 7am – 10pm 55 dB LAeq Sunday, 9am – 6pm

• At all other times 45 dB LAeq

60 dB Leq (63 Hz) and 55 dB Leq (125 Hz) 75 dB LAFmax

There are no applicable noise limits for activities in the Coastal – Marina Zone received in nearby Business zones (e.g. Business – City Centre Zone and Business – Mixed Use Zone in Wynyard Quarter). However, the noise limits applying within the Business zones are generally lenient and accommodating of the marine industry activities.

3.2 Construction Noise (Airborne)

AUP OIP rule E25.6.27 reproduces the construction noise limits from Tables 2 and 3 of New Zealand Standard NZS 6803: 1999 “Acoustics - Construction Noise”. Construction of this nature usually exceeds 20 weeks duration and the normal working hours are usually between 7.30am and 6pm, Monday to Saturday. Therefore, the relevant daytime construction noise limits are 70 dB LAeq and 85 dB LAFmax.

Site




3.3 Construction Noise (Underwater)

3.3.1 Overview

Section F2.18 of the AUP OIP includes objectives and policies relating to the management of the adverse effects of underwater noise on marine mammals. Table F2.19.8 (A114) classifies “underwater blasting, impact and vibratory piling, and marine seismic surveys” as restricted discretionary activities. Therefore, an assessment of underwater noise effects is required for this project due to the use of impact and/or vibratory piling.

The assessment would also need to address effects from any capital dredging works, but the rule specifically excludes underwater noise generated by “the operational requirements of vessels (including cargo vessels, tugs, passenger liners, naval vessels and commercial fishing vessels), use of sonar, and temporary activities other than construction”.

Although there are no underwater noise standards, F2.23.1.3(c) identifies specific matters for discretion and F2.23.2.7 includes various matters for assessment as follows:

• The health and well-being of marine fauna (including threatened and at-risk species) and people from the noise associated with the proposal

• The practicability of being able to control the noise effects

• The social and economic benefits to the community of the proposal

• The extent to which the adverse effects of the noise will be mitigated

There is no New Zealand guidance on underwater noise effects. However, the US Department of Commerce National Oceanic and Atmospheric Administration has provided guidance for assessing the effects of anthropogenic (human-made) sound on marine mammals1 (referred to as the ‘NOAA Guidelines’). This US statute does not apply in New Zealand, but the NOAA Guidelines are provided to give context to the underwater noise assessment.

3.3.2 Species of Interest

Based on our experience from other projects in the Waitemata Harbour, and in consultation with the project marine ecologist2, bottlenose dolphins, common dolphins and orca have been identified as the primary species of interest. These species are all classified as mid-frequency (MF) cetaceans for the purposes of underwater noise sensitivity.

We also understand, through anecdotal sightings, that a leopard seal is currently resident in Westhaven Marina. Leopard seals are classified as Phocid pinnipeds (PW) for the purposes of underwater noise sensitivity.

1 National Oceanic and Atmospheric Administration: ‘Technical Guidance for Assessing the Effects on Anthropogenic Sound on Marine Mammal Hearing’ (July 2016)

2 Simon West, Bioresearches Group Ltd

3 TTS in humans can be likened to the ‘muffled’ effect on hearing after being exposed to high noise levels such as at a concert. The effect eventually goes away, but the longer the exposure, the longer the threshold shift lasts. Eventually, the TTS becomes permanent

3.3.3 Marine Mammals – Physiological Impacts

The NOAA Guidelines identify the received levels above which individual marine mammals are predicted to experience changes in hearing sensitivity. These changes are either temporary (‘Temporary Threshold Shift’ or TTS), or permanent (‘Permanent Threshold Shift’ or PTS)3. Auditory threshold shifts can be caused from peak exposure (high-level impulsive events such as pile strikes) or from cumulative exposure (lower noise levels over an extended period such as from vibro-piling or multiple pile strikes).

The NOAA Guidelines provide TTS and PTS onset thresholds for mid-frequency cetaceans using ‘peak’ and ‘SELcum’ assessment descriptors. The peak level is the highest un-weighted instantaneous pressure level recorded during the measurement period, whereas SELcum is the species-weighted cumulative sound exposure level over a 24-hour period. The criteria are summarised in Table 1.

Table 1: Summary of NOAA TTS and PTS Thresholds

Thresholds4

Species Threshold Type Impulsive (e.g. impact piling) Non-Impulsive (e.g. vibro piling)

Mid-Frequency Cetaceans TTS 224 dB Lpeak 170 dB SELcum (mf)

178 dB SELcum (mf)

PTS 230 dB Lpeak 185 dB SELcum (mf)

198 dB SELcum (mf)

Phocid Pinnipeds TTS 212 dB Lpeak 170 dB SELcum (ow)

181 dB SELcum (ow)

PTS 218 dB Lpeak 185 dB SELcum (ow)

201 dB SELcum (ow)

3.3.4 Marine Mammals – Behavioural Impacts

Behavioural responses to underwater noise can vary significantly depending on species, the noise environment, and the frequency content of the noise source. These effects can range from temporary avoidance of the noisy area to disorientation or impeded communication.

Relatively little is known about the thresholds above which there are likely to be behavioural impacts. As interim

guidance, NOAA states that behavioural impacts can occur at levels of 160 dB re. 1 Pa rms for impact piling, and

as low as 120 dB re. 1 Pa rms for vibratory driven piles depending on the noise environment. However, it should be noted that these thresholds are recognised by NOAA to be conservative, and are only interim criteria until formal guidance is available.

3.3.5 Criteria for Divers

The US Navy (US Federal Register, 2002) states there are no adverse noise effects below 145 dB re 1 Pa rms.

However, changing heart rates or breathing frequency have been found to occur above 154 dB re 1 Pa rms. Safety guidelines for human divers published in a NATO Undersea Research Centre (NURC) publication5 recommends military divers should avoid areas where noise levels exceed 160 dB re 1 μPa rms (125Hz – 4kHz). This is considered an acceptable threshold for experienced divers near the proposed works and aligns with the marine mammal behavioural response threshold for impulsive sources (impact piling) above.

4 SEL thresholds are in dB re 1 μPa2s and peak SPL thresholds are in dB re 1 μPa

5 ‘NATO Undersea Research Centre Human Diver and Marine Mammal Risk Mitigation Rules and Procedures’, NURC-SP-2006-008, September 2006




4.0 EXISTING ENVIRONMENT

4.1 Overview

Noise levels were measured in the project vicinity to quantify the existing noise environment. An airborne measurement was carried out at the closest residential receiver (MP1 on Figure 3), and underwater noise measurements were carried out in the harbour area surrounding the marina (MP2 – MP4 on Figure 3).

Figure 3: Existing Noise Environment Measurement Locations

4.2 Airborne Noise

An airborne noise measurement was undertaken adjacent to 12 Amaria Street, St Mary’s Bay, which was the closest accessible receiver location. Weather conditions were fine during the survey, with little to no wind and 4/8 okta cloud cover.

The noise environment was dominated by road traffic on State Highway 1, located between the Marina and the closest residential areas. The measurements are summarised in Table 2.

Table 2: Summary of Measured Airborne Noise Levels

Measured Levels (dB)

Time Duration LAmax LAeq LA90 Noise Sources

2:27pm – 2:44pm 15 min 68 58 55 Traffic on SH1 (dominant), birds, traffic on Amiria St

4.3 Underwater Noise

Underwater noise levels were measured at the three locations for a period of two weeks (17 November – 1 December 2017). The locations are considered representative of the receiving environment near the marina. See Appendix C for hydrophone and rigging details.

The existing underwater noise environment was generally controlled by vessel movements during the daytime. The measurements were also affected by tidal movements at low frequency (63Hz and below).

Figure 4 presents a spectrogram of a typical day at MP3, with the controlling noise sources labelled. Figure 5 presents the measured RMS levels in 15 minute periods over the survey period, and Figure 6 presents the same results with noise below 63Hz excluded (i.e. tidal flow noise excluded). A summary table of the results including average levels, ranges and peak levels is shown in Table 3 overleaf.

Figure 4: Spectrogram of a Typical Day at MP3 (dB re. 1 μPa rms (1sec) in 1/3 octave bands)

Figure 5: Measured Noise Levels over Survey Period (dB re. 1 μPa rms (15 min))

Figure 6: Measured Noise Levels over Survey Period – 63Hz and below excluded (dB re. 1 μPa rms(15 min))

MP3 - Hydrophone

MP2 - Hydrophone

MP1 - Airborne

MP4 - Hydrophone

Site

Vessel movements

Tidal Flow Snapping shrimp




Table 3: Summary of Measured Underwater Noise Levels

Position Period Measured Levels (dB re 1 μPa)

RMS (15min) (10 Hz – 24 kHz)

RMS (15min) (63 Hz – 24 kHz)

Lpeak (1 sec)

MP2 Day (0700 – 2200) 129 122 162

Night (2200 – 0700) 127 116 163

MP3 Day (0700 – 2200) 124 119 166

Night (2200 – 0700) 124 118 168

MP4 Day (0700 – 2200) 125 124 173

Night (2200 – 0700) 123 123 174

5.0 CONSTRUCTION ASSESSMENT

5.1 Methodology

The marina extension is predicted to be constructed over a 12-month period. The main construction activities are shown in Table 4 below.

Table 4: Summary of Construction Activities

Activity Description

Dredging Approximately 75,000m3 of material will need to be dredged for the reclamation

Mudcrete mixing Dredged material is mixed with cement, likely on a floating barge

Placement of mudcrete and armour rock

13,000m2 mudcrete foundation will be formed on the sea bed, with armour rock placed on the sloping faces

Piling Installation of piles for berths, pontoons and promenade using either drilled, impact or vibro-piling methods

5.2 Airborne Noise

The closest occupied building within the Marina is the Royal New Zealand Yacht Club facility to the west of the breakwater extension. The closest noise sensitive receivers outside the Marina is in St Mary’s Bay, approximately 600m to the south of the works area.

Impact piling is predicted to be one of the loudest, and the most intrusive, construction activity. Noise contours for impact piling are included as Figure 7. In summary, construction noise is predicted to readily comply with the relevant daytime noise limits, Monday To Saturday. Furthermore, construction would rarely be audible in residential areas due to the high ambient noise levels generated by State Highway 1 road traffic noise.

Figure 7: Impact Piling Noise Contours




5.3 Underwater Noise

5.3.1 Overview

Piling is predicted to produce the highest levels of underwater construction noise. Noise levels are dependent on the installation method (impact, vibro or drilled), pile type (steel, concrete or timber), pile size and mitigation. Noise propagation underwater is dependent on the bathymetry in the project vicinity and seafloor properties (rock, sand, mud etc.).

5.3.2 Source Levels

Comparable reference measurements6 for the different pile sizes are summarised in Table 5. The equivalent species-weighted cumulative SEL7 has also been calculated in each case.

Table 5: Pile driving underwater noise levels

Size and Method Source Levels (dB re 1μPa at 10m)

Details Peak RMS SELSS SELcum (MF) SELcum (PW)

Vibratory driven 600mm steel

2 hours of driving/day* 180 170 N/A 190 200

Impact driven 600mm steel

900 strikes/day* 200 180 167 178 190

* Based on installation of 6 piles per day

5.3.3 Noise Modelling

Modelling of impact piling noise levels has been undertaken using dBSea, which is a 3D underwater noise software that enables spatial visualisation for the various zones of influence. The model inputs are summarised as follows:

• Bathymetry provided by BECA and supplemented by data from LINZ

• Source spectrums based on in-water measurements of impact driven steel piles8 between 20Hz – 20kHz, scaled to the levels provided in Table 5

• The noise contours are calculated using a Parabolic Equation (‘PE’) solver for frequencies below 2kHz and a ‘Ray Trace’ solver above 2kHz. The cross over is considered suitable for depths of between 5 and 20m found in Waitemata Harbour

• Seafloor is assumed to be mud with sandstone beneath, and the speed of sound is assumed to be constant in the water column

5.3.4 Predicted Zones of Influence

The predicted zones of influence for the proposed piling works are presented in Table 6. These zones are based on the criteria provided in the NOAA guidelines (refer Section 3.3.3). The zones of influence have been provided as distances from the pile being installed.

6 Impact driven concrete and timber piles – California Department of Transportation: ‘Technical Guidance for Assessment and Mitigation of the Hydroacoustic Effects of Pile Driving on Fish’ (Nov 2015), Table VI-1

7 The cumulative sound exposure level is the total sound energy over a 24-hour period normalized to 1 second. This parameter removes the duration component from the noise level, allowing impulsive and non-impulsive noise sources such as impact and vibratory piling to be compared.

Table 6: Zones of Influence

Threshold

Zones

Species Vibro-piling

(600mm steel piles) Impact piling

(600mm steel piles)

All species PTS – peak Below criteria Below criteria

TTS – peak Below criteria Below criteria

Behavioural response 180m 230m

Mid-frequency cetaceans TTS – cumulative exposure 100m 70m

Phocid pinnipeds PTS – cumulative exposure <10m 60m

TTS – cumulative exposure 200m 230m

Noise levels from the proposed piling works are predicted to be below the thresholds for peak PTS for both mid-frequency cetaceans and phocid pinnipeds, and the PTS cumulative exposure is not predicted to be exceeded for mid-frequency cetaceans. For phocid pinnipeds (i.e. the leopard seal), the cumulative PTS threshold is predicted to be exceeded within 60m of the impact piling rig.

The TTS thresholds for peak levels are not predicted to be exceeded. However, there is a potential for TTS from cumulative exposure if a marine mammal is within 100m of any vibro-piling or 70m of any impact piling, and for a phocid pinniped within 200m of vibro piling and 230m of impact piling.

Potential behavioural response is expected within 180m – 230m of the piling location, beyond which masking and audibility effects may also be apparent. However, the it is understood that the Waitemata Harbour is not a critical habitat for the identified species of interest. They are transient occupants rather than permanent residents of the harbour. Furthermore, the piling activities are of a temporary nature.

Figure 8 graphically illustrates the underwater noise management zones for both types of piling.

Overall, the underwater noise effects from piling activities are considered reasonable with the application of a suitable construction noise management plan (refer Section 5.5).

5.4 Underwater Noise from Dredging

Underwater noise from backhoe dredging is primarily produced by the barge engine and propeller cavitation during transit to and from the dredging and disposal areas. There is also noise generated by excavation activities, such as the excavator bucket striking the seabed, however, this is negligible and not considered further.

Measurements of dredging vessels9 indicate that source levels can range from 154 – 179 dB re 1 μPa rms at 1m. These source levels would be similar to the majority of medium to large size vessels currently travelling in the Waitemata Harbour, and while the dredging would operate for longer periods in the same location, it is considered that the overall level and character would be generally comparable to existing vessel movements.

The potential noise effects are considered to be local, behavioural (as opposed to physical trauma) and comparable in scale to existing marina vessel activities.

8 ITAP –Institut für technische und angewandte Physik GmbH: ‘Spektren der Vibrationsramme beim Umspannwerk’ (2011)

9 Terra et Aqua, Number 144, September 2016: ‘Dredging Sound Levels, Numerical Modelling and EIA’




Figure 8: Underwater Management Zones

Piling location




5.5 Construction Noise Management

The following procedure should be implemented to manage the effects of underwater noise on marine mammals and divers:

• Undertake visual monitoring 30 minutes prior to commencing piling operations to ensure there are no marine mammals and divers in the area

• Use a wooden (preferable) or plastic dolly for the steel piles

• Use ‘soft starts’ (gradually increasing the intensity of impact piling) and minimise duty cycle

• Undertake visual monitoring during piling operations to identify any marine mammals that enter the area

• Implement low power or shut down procedures when a marine mammal is identified within the TTS zones (based on the current methodology, Table 6 identifies a zone of up to 230m)

This procedure is included as a proposed condition of any consent granted in Section 7.0.

6.0 OPERATIONAL NOISE

Westhaven Marina is a large development consisting of around 2,000 berths and moorings, car parking and several commercial businesses. The proposed extension to the north of the existing marina is to provide 117 berths and 103 car parks, which would account for around 5% of the overall marina activities. The change in noise level associated with this increase in intensity of use is negligible. Furthermore, the nearest receivers are a significant distance away and their noise environment is dominated by SH1 road traffic movements. Noise from the marina extension is unlikely to be discernible above the existing noise levels in the vicinity.

7.0 CONDITIONS OF CONSENT

The following conditions of consent are proposed:

1. To manage underwater noise effects on marine mammals and divers:

• Undertake visual monitoring 30 minutes prior to commencing piling operations to ensure there are no marine mammals and divers in the area

• Use a wooden (preferable) or plastic dolly for the steel piles

• Use ‘soft starts’ (gradually increasing the intensity of impact piling) and minimise duty cycle

• Undertake visual monitoring during piling operations to identify any marine mammals that enter the area

• Implement low power or shut down procedures when a marine mammal is identified within the TTS zones

MDA report (‘Rp 001 20170963’, dated 22 December 2017) identifies TTS zones of up to 230m. The zones must be updated prior to piling commencing and in response to monitoring results (refer condition 2).

2. Monitoring of underwater noise levels is to be undertaken during the first impact or vibratory pile driving works to confirm the predicted underwater noise levels and management zones.

8.0 CONCLUSIONS

MDA has undertaken an acoustic assessment of the proposed Westhaven Marina Extension. In summary:

• The existing noise environment is generally controlled by SH1 road traffic

• Marina noise is predicted to comply with the relevant limits and the noise effects are negligible

• Construction noise is predicted to comply with the relevant airborne noise limits

• Underwater noise effects should be managed by implementing low power or shut down procedures for the piling works when a marine mammal and diver is identified within the TTS zones

• Conditions for any consent granted are proposed in Section 7.0




APPENDIX A GLOSSARY OF TERMS

dB Decibel (dB) is the unit of sound level. Expressed as a logarithmic ratio of sound pressure (P) relative to a reference pressure (Pr), where dB = 20 x log(P/Pr). The

convention is a reference pressure of Pr = 20 Pa in air and Pr = 1 Pa underwater.

dBA The unit of sound level which has its frequency characteristics modified by a filter (A-weighted) so as to more closely approximate the frequency bias of the human ear. A-weighting is used in airborne acoustics.

LAeq (t) The equivalent continuous (time-averaged) A-weighted sound level. This is commonly referred to as the average noise level. The suffix "t" represents the time period to which the noise level relates, e.g. (8 h) would represent a period of 8 hours, (15 min) would represent a period of 15 minutes and (2200-0700) would represent a measurement time between 10 pm and 7 am.

LA90 (t) The A-weighted noise level equalled or exceeded for 90% of the measurement period. This is commonly referred to as the background noise level.

LAmax The A-weighted maximum noise level. The highest noise level which occurs during the measurement period.

Lpeak The peak instantaneous pressure level recorded during the measurement period (normally not A-weighted).

SEL Sound exposure level (SEL) is the constant sound level acting for a reference period (typically a one second period in air and a 24 hour ‘cumulative’ period underwater denoted by the addition of subscript ‘cum’). It is the time-integrated, sound-pressure-squared level. SEL is typically used to compare transient sound events having different time durations, pressure levels and temporal characteristics.

TTS Temporary Threshold Shift (TTS) is the temporary loss of hearing as a result of exposure to sound over time. Exposure to high levels of sound over relatively short time periods will cause the same amount of TTS as exposure to lower levels of sound over longer time periods. The mechanisms underlying TTS are not well understood, but there may be some temporary damage to the sensory hair cells. The duration of TTS varies depending on the nature of the stimulus, but there is generally recovery of full hearing over time.

PTS Permanent Threshold Shift (PTS) is the permanent loss of hearing caused by some kind of acoustic or trauma. PTS results in irreversible damage to the sensory hair cells of the ear, and thus a permanent loss of hearing

Ambient The ambient noise level is the noise level measured in the absence of the intrusive noise or the noise requiring control. Ambient noise levels are frequently measured to determine the situation prior to the addition of a new noise source.

Special Audible Characteristics

Distinctive characteristics of a sound which are likely to subjectively cause adverse community response at lower levels than a sound without such characteristics. Examples are tonality (e.g. a hum or a whine) and impulsiveness (e.g. bangs or thumps).

NZS 6801:2008 NZS 6801:2008 “Acoustics – Measurement of environmental sound”

NZS 6802:2008 NZS 6802:2008 “Acoustics – Environmental Noise”

APPENDIX B AUP OIP PLANNING MAP

APPENDIX C HYDROPHONE AND RIGGING DETAILS

Soundtrap 201 hydrophones were used for the underwater noise measurements. The hydrophones measured over a frequency range of 10Hz – 48kHz.

The figure below shows the rigging arrangement.

Coastal – Marina Zone

Business – City Centre Zone

Residential Zones

Site

Hydrophone Surface buoy

>5m

Anchors / weights

Sub-surface buoy

1 – 2m

Hydrophone

2 – 10m (approximately half water depth)

Antenna

>5m


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