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REVERB ACOUSTICS PTY LTD ABN 90 045 630 639 ACN 142 127 768 PO Box 181 ADAMSTOWN NSW 2289

Telephone: (02) 4947 9980 email: [email protected]

Noise Impact Assessment Modifications to Waitara Oval Relocation of Tennis Courts Waitara NSW July 2015

Prepared for Hornsby Shire Council Report No. 15-1896-R1

mailto:[email protected]

Hornsby Shire Council Noise Impact Assessment – Modifications to Waitara Oval Relocation of Tennis Courts of 14

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July 2015 Document Ref: 15-1896-R1 Commercial in Confidence

TABLE OF CONTENTS

1. INTRODUCTION ................................................................................................................ 3

2. TECHNICAL REFERENCE / DOCUMENTS ...................................................................... 3

3. DESCRIPTION OF PROPOSAL ........................................................................................ 4

4. EXISTING ACOUSTIC ENVIRONMENT ............................................................................ 5

5. CRITERIA .......................................................................................................................... 6

6. METHODOLOGY ............................................................................................................... 7

7. ANALYSIS ......................................................................................................................... 8

8. SUMMARY OF RECOMMENDED NOISE CONTROL ....................................................... 9

9. CONCLUSION ................................................................................................................. 10

APPENDIX A

DEFINITION OF ACOUSTIC TERMS .................................................................................. 11

APPENDIX B ACOUSTIC FENCE LOCATIONS ........................................................................................ 13

COMMERCIAL IN CONFIDENCE In order to protect the integrity and proper use of this document, it may be copied in full providing it is complete and securely bound. Consider separate pages of this report in

contravention of copyright laws.


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1 INTRODUCTION Reverb Acoustics has been commissioned to conduct a noise impact assessment for modifications to Waitara Oval, specifically relocation of tennis courts from the southern end of the site to the northern end. The purpose of this assessment is to theoretically determine the noise impact operation of the tennis courts will have on nearby residential receivers. The courts will be used for social tennis games, squad, training, tournaments and social hire. We understand that a PA system will not be used at the courts. No changes are proposed for parking and no new mechanical plant will be installed as part of the proposal. Further assessment has been undertaken to determine the noise impact on patrons at the relocated tennis courts from passing road traffic on nearby arterial roads. The assessment was requested by Hornsby Shire Council (HSC) to form part of and in support of a Development Application for the proposal and to ensure any noise control measures are incorporated into the design of the centre.

2 TECHNICAL REFERENCE / DOCUMENTS Bies, D.A. and Hansen, C.H. (1996). Engineering Noise Control: Theory and Practice. London, E & F.N. Spon. Gréhant B. (1996). Acoustics in Buildings. Thomas Telford Publishing. Templeton, D. (1997). Acoustics in the Built Environment. Reed Education and Professional Publishing Ltd. AS 2107-2000 “Acoustics-Recommended Design Sound Levels and Reverberation Times for Building Interiors”. AS 1276.1-1999 “Acoustics – Rating of sound insulation in buildings and of building elements. Part 1: Airborne sound insulation”. NSW Environment Protection Authority (2000). Industrial Noise Policy NSW Environment Protection Authority (1999). Environmental Criteria for Road Traffic Noise NSW Roads and Traffic Authority (2001). Environmental Noise Management Manual Plans supplied by Hornsby Shire Council. Note that variations from the design supplied to us may affect the acoustic recommendations. A Glossary of commonly used acoustical terms is presented in Appendix A to aid the reader in understanding the Report.

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3 DESCRIPTION OF PROPOSAL HSC seek Development Consent for relocation of tennis courts from the southern end of Waitara Oval to the northern end. The tennis courts will be used for social tennis games, squad, training, tournaments and social hire. Proposed operating hours are as follows:

- 9am to 10pm Monday to Friday - 8am to 7pm on Saturday - 9am to 7pm on Sunday.

Potential noise sources, which may impact upon nearby residential neighbours include raised voices and ball impacts. We understand that a PA system will not be used at the courts. The assessment includes measurement of the existing acoustic environment at the site over several days to provide baseline data and enable establishment of noise assessment criteria. Plans supplied by HSC show the layout of the site and the location of nearby land uses. Nearest receivers identified during our site visits are as follows (also see Figure 1): R1 – Multi-storey residential apartments. R2 – Multi-storey residential apartments. R3 – Residences. R4 – Residences.

Figure 1: Site Plan


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4 EXISTING ACOUSTIC ENVIRONMENT A background and ambient noise level survey was conducted using a Type 1, Svan 949 environmental noise logging monitor, installed in a weatherproof security cage at the north east corner of the site, approximately 15 metres from the near lane of traffic on Edgeworth David Avenue (see Figure 1). The selected location is representative of the acoustic environment in the receiver area and is considered an acceptable location for determination of the background noise levels in accordance with Appendix B of the Office of Environment and Heritage’s (OEH’s) Industrial Noise Policy (INP). Sound levels were continuously monitored from 7 June to 14 June 2015, to determine the existing background and ambient noise levels for the area. The instrument was programmed to accumulate environmental noise data continuously and store results in internal memory. The data were then analysed to determine 15 minute Leq and statistical noise levels using dedicated software supplied with the instrument. The instrument was calibrated with a Brüel and Kjaer 4230 sound level calibrator producing 94dB at 1kHz before and after the monitoring period, as part of the instrument’s programming and downloading procedure, and showed an error less than 0.5dB. Additional traffic noise monitoring was conducted on the north west corner of the site, approximately 5 metres from the near lane of traffic, during peak morning and afternoon periods from 7am-9am. Tables 1 and 2 shows results of our noise survey, included in Table 1 are the Assessment Background Levels (ABL’s), for the day, evening and night periods. From these ABL’s the Rating Background Level (RBL) has been calculated, according to the procedures described in the OEH’s INP and by following the procedures and guidelines detailed in Australian Standard AS1055-1997, "Acoustics - Description and Measurement of Environmental Noise, Part 1 General Procedures". A complete set of logger results is not shown, but available on request.

Table 1: Summary of Noise Logger Results – Newcastle Road, dB(A) Time

Period Background L90 Ambient Leq

Day 7am-6pm

Evening 6pm-10pm

Night 10pm-7am

Day 7am-6pm

Evening 6pm-10pm

Night 10pm-7am

7-8 June - 44.8 35.7 - 57.3 51.3

8-9 June 45.7 44.3 37.9 59.2 57.4 56.1

9-10 June 53.5 46.1 38.0 62.1 58.5 57.6

10-11 June 55.4 47.2 37.9 63.0 58.5 55.3

11-12 June 55.0 48.2 35.6 62.0 60.3 55.0

12-13 June 53.8 48.6 35.9 61.6 58.8 53.0

13-14 June 54.5 48.2 36.6 63.2 58.2 53.7

RBL* 54.1 47.2 36.6 -- -- --

LAeq -- -- -- 62.0 58.5 55.0 * RBL - Rating Background Level, median value of each ABL over the entire monitoring period. The ABL is a single figure representing the "L90 of the L90’s", as recommended by the DEC, for each separate day of monitoring.

Table 2: Measured Traffic Noise Levels – Edgeworth David Avenue

Descriptor Noise Level dB(A) Time Interval

Leq,1hr (day) 62.8 07:00 to 22:00

Leq,1hr (night) 58.1 22:00 to 07:00

Leq,8hr 53.6 22:00 to 06:00

Leq,9hr 55.0 22:00 to 07:00

Leq,15hr 60.9 07:00 to 22:00

Leq,16hr 60.8 06:00 to 22:00

Leq,24hr 59.5 06:00 to 06:00


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Site, weather and measuring conditions were all satisfactory during the noise survey. We therefore see no serious reason to modify the results because of influencing factors related to the site, weather or our measuring techniques. A summary of the measured noise environment at the site appears in Table 3, taken from our logger results.

Table 3: Existing Noise levels Time Leq Lmax L10 L90

Period Range Average Range Average Range Average Range Average

Day 54-69 61 65-90 75 58-68 63 44-59 55

Evening 55-63 58 63-85 70 58-64 61 43-57 50

Night 42-70 52 58-95 67 40-67 55 35-59 41

5 CRITERIA

5.1 Road Traffic Noise (Impact on Proposal) The OEH’s NSW Road Noise Policy is the most recent document for assessment of road traffic noise impacts on various sensitive land use types. The Guideline recommends the following assessment criteria for open space/recreational areas: Open Space (active use) 60dB(A),Leq (15 hour) Active recreation is characterised by sporting activities and activities which generate their own noise or focus for participants, making them less sensitive to external noise intrusion Open Space (passive use) 55dB(A),Leq (15 hour) The Guideline suggests that In determining whether areas are used for active or passive recreation, the type of activity that occurs in that area and its sensitivity to noise intrusion should be established. For areas where there may be a mix of passive and active recreation, e.g. school playgrounds, the more stringent criteria apply. We consider the tennis courts to be a mix of passive and active use and have therefore adopted the more stringent passive use criterion for assessment purposes, i.e. 55dB(A),Leq (15 hour).

5.2 Site Noise (Impact on Nearby Neighbours) Noise from industrial noise sources scheduled under the Protection of Environment Operations Act is assessed using the OEH’s INP. However, local Councils may also apply the criteria for land use planning, compliance and complaints management. The INP specifies two separate criteria designed to ensure existing and future developments meet environmental noise objectives. The first limits intrusive noise to 5dB(A) above the background noise level and the other aims to protect against progressively increasing noise in developing areas, based on the existing (Leq) noise level from industrial noise sources. Project Specific Noise Levels are established for new developments by applying both criteria to the situation and adopting the more stringent of the two. The existing L(A)eq for the receiver area is dominated by traffic on nearby roads and some commercial activity. Reference to Table 2.1 of the INP shows that the area is classified as urban. Industrial noise contributions are more than 6dB(A) below the recommended Leq, so the recommended Acceptable Noise Level (ANL) applies in this case, i.e. no ANL reduction required for industrial noise contributions.


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Table 4 below specifies the applicable base objectives for the proposed development. In high traffic areas where the existing traffic noise levels are at least 10dB above the Acceptable Noise Level, the high traffic amenity criterion applies.

Table 4: - Base Noise Level Objectives

Period Intrusiveness Criteria Amenity Criteria

Day 59 (54+5) 60

Evening 52 (47+5) 50

Night 42 (37+5) 45 (55-10)

Receiver Type: Urban (See OEH’s INP - Table 2.1)

Project specific noise levels, determined as the more stringent of the intrusiveness criteria and the amenity / high traffic criteria, are as follows: Day 59dB LAeq,15 Minute 7am to 6pm Mon to Sat or 8am to 6pm Sun and Pub Hol. Evening 50dB LAeq,15 Minute 6pm to 10pm Night 42dB LAeq,15 Minute 10pm to 7am Mon to Sat or 10pm to 8am Sun and Pub Hol.

6 METHODOLOGY

6.1 Road Traffic Noise (Impact on Proposal) Applicable noise level metrics are those calculated from our measurements at the site. A +2.5dB(A) facade adjustment must be applied to our results, as measurements were conducted in the free-field. Received traffic noise for 2015 was calculated as follows:

received noise (free field) + facade correction = received noise Applying the above formula gives: Day 62.8dB(A) + 2.5dB(A) = 65.3dB(A) Leq15hr 7am – 10pm Reference to nearby RMS traffic stations indicate that approximately 22,000 vehicles pass the site each day along Edgeworth David Avenue, projected to the year 2015. A figure of 5% heavy vehicles has been adopted. The AADT for the year 2015 was applied to our computer programme, based on the OEH and RMS approved CORTN Method of Traffic Noise Prediction, and noise levels were calculated at various locations over the courts. The CoRTN values are merely arbitrary, as calculated noise levels are adjusted to correlate with our measured peak external noise levels, with the intention is to provide a (theoretical) means of determining the degree of noise control required for the site. Equivalent continuous noise levels were calculated for each traffic lane separately on the basis that the noise source (i.e. the traffic) was located in approximately the centre of the respective lane. In particular, this gives an accurate estimation of the location of bus and truck exhausts which are generally located on the right hand side, being approximately at the same point for both traffic directions. Our calculations have been modified to compensate for the differing acoustic centres of cars and heavy vehicles, by modelling each separately and logarithmically adding received noise levels.


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6.1.1 CoRTN Model Conversion The OEH released their ECRTN in June 1999 and RNP in 2011, which specify modified assessment periods for day and night, namely, Leq,15hr (7am to 10pm) and Leq,9hr (10pm to 7am). These assessment periods have rendered the original Australian version of the CoRTN model invalid, which was designed to assess the impact over a single 24 or 18 hour period. Consequently, modification of the Model is required to adequately describe the new metrics. The CoRTN algorithm pertaining to traffic flow percentages has been modified by inserting all AADT figures for arterial roads, contained in RTA publications - Traffic Volume Data for Hunter and Northern Regions, 1998, and establishing AADT figures for the applicable day and night periods. Our CoRTN model was then calibrated against long term measurements made at locations with reliable AADT figures.

6.2 Site Noise (Impact on Nearby Neighbours) Future noise sources on the site were not measured during peak usage periods, consequently typical noise levels from similar developments have been sourced from our library of technical data. This library has been accumulated from measurements taken in many similar situations on other sites, and allows theoretical predictions of future noise impacts at each receiver and recommendations concerning noise control measures to be incorporated in the design of the site. The calculated acoustic sound power (dB re 1pW) for all likely noise sources on the site is then theoretically propagated to the receiver, taking into account attenuation due to distance, topographical features and any intervening barriers. Atmospheric absorption, directivity and ground absorption have been ignored in the calculations. Where noise impacts above the criteria are identified, suitable noise control measures are implemented and reassessed to demonstrate satisfactory received noise levels in the residential area.

7 ANALYSIS

7.1 Received Noise Levels – Road Traffic (Impact on Proposal) Shown below is a sample calculation detailing the procedure followed in order to calculate the noise impact in the centre of the courts, assuming an acoustic barrier . The traffic noise level at the outer face of the glazing is calculated as follows,

Table 5: Sample Calculation – Road Traffic Noise Impact on Tennis Courts

Octave band Sound Pressure Levels, dB(A)

Propagation calculation dB(A) 63 125 250 500 1k 2k 4k 8k

Traffic noise, Leq1 65 45 53 54 58 60 57 51 43

Traffic noise centre of courts 55 40 46 48 50 48 45 36 24 1. Noise level at north edge of court. Allowance made for 2400mm acoustic barrier.

As can be seen by the above results, an acoustic barrier 2400mm above ground level will need to be erected between the courts and traffic on Edgeworth David Avenue to reduce noise levels to the adopted criterion of 55dB(A),Leq. See Section 8 for barrier construction details and locations.


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7.2 Tennis Court Usage (Impact on Nearby Neighbours)

Usage of the tennis courts for social tennis games, squad, training, tournaments and social hire has the potential to create unacceptable noise levels at nearest receivers. To create our acoustic model we have assumed a worst-case situation where all courts are being used during a tournament, with intermittent audience participation. The sources were placed randomly over the available areas and the resulting sound pressure level was propagated to nearest residences using an equation giving the sound field due to an incoherent plane radiator. The following Table shows results of our calculations.

Table 6: Noise Impact from Tennis Court Usage, dB(A),Leq. Propagated to Nearest Residences

Location/Activity Tennis Courts/Receivers

R1 R2 R3 R4

Received 45 43 44 42

Criteria (day/evening) 59dB(A),Leq (15 minute) / 50dB(A),Leq (15 minute)

Impact 0 0 0 0

As can be seen by the results in the above Table, noise from tennis court activities is predicted to be compliant with the criteria at nearest residential receivers during the day and evening. See Section 8 for detailed acoustic recommendations.

8 SUMMARY OF RECOMMENDED NOISE CONTROL 1. The following court operating hours are acceptable:

- 9am to 10pm Monday to Friday - 8am to 7pm on Saturday - 9am to 7pm on Sunday.

2. No PA system is permitted at the courts. 3. Acoustic fences are to be erected on top of the existing retaining walls at the following locations (also see Appendix B):

Location Total Height Above Court Level (Retaining Wall and Acoustic Fence) North Court Perimeter 2400mm East/West Court Perimeter 2400mm above court level north end & 1000mm south end 4. Acceptable forms of acoustic fence construction include lapped and capped timber, Hebel Powerpanel, masonry, safety glass panels, etc. No significant gaps should remain in the fence/wall to allow the passage of sound below the recommended height. Other construction options are available if desired, providing the fence or wall is impervious and of equivalent or greater surface mass than the above construction options. The above noise control recommendations are not necessarily the only options available, but are expected to be the most cost-effective and practical with the information currently to hand. Alternative options can be considered provided they result in the same or lower received noise levels at any nearby residence.


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9 CONCLUSION A noise impact assessment for relocation of tennis courts from the southern end of Waitara Oval to the northern end, has been completed. The assessment has shown that the new location is suitable for the intended purpose, subject to our recommendations. With these or equivalent measures in place, noise from the site will be either within the criteria or generally below the existing noise level in the area for the majority of the time. This assessment is based on a worst-case situation, i.e. all courts being used during a tournament, while in reality many activities will not always be taking place in the most exposed areas, so actual received noise levels are expected to be less than the predictions shown in this report, or at worst equal to the predicted noise levels for only part of the time. An assessment of road traffic noise impacting on court usage has resulted in recommendation of acoustic fences along the north, east and west perimeter of the courts to satisfy the requirements of the OEH, DOPI and HSC. Subject to noise control recommendations discussed within this report, this assessment has shown operation of the relocated tennis courts should result in minimal impact on the surrounding residential area. Therefore, with the proposed noise control measures and strategies incorporated into the design, we see no acoustic reason why the proposal should be denied.


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APPENDIX A Definition of Acoustic Terms


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Definition of Acoustic Terms

Term Definition

dB(A) A unit of measurement in decibels (A), of sound pressure level which has its frequency characteristics modified by a filter ("A-weighted") so as to more closely approximate the frequency response of the human ear.

ABL Assessment Background Level – A single figure representing each individual assessment period (day, evening, night). Determined as the L90 of the L90’s for each separate period.

RBL Rating Background Level – The overall single figure background level for each assessment period (day, evening, night) over the entire monitoring period.

Leq Equivalent Continuous Noise Level - which, lasting for as long as a given noise event has the same amount of acoustic energy as the given event.

L90 The noise level which is equalled or exceeded for 90% of the measurement period. An indicator of the mean minimum noise level, and is used in Australia as the descriptor for background or ambient noise (usually in dBA).

L10 The noise level which is equalled or exceeded for 10% of the measurement period. L10 is an indicator of the mean maximum noise level, and was previously used in Australia as the descriptor for intrusive noise (usually in dBA).


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APPENDIX B Acoustic Fence Locations


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