1 · web viewan indicative worst case assessment of the properties within the new development,...

Mid Devon District Council

Tiverton Eastern Urban Extension

(Site B)

Tiverton

Noise AssessmentMay 2016Executive Park, Avalon Way, Anstey, Leicester, LE7 7GRTel: +44 (0)116 234 8000Email: [email protected]

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Document Control

Project: Tiverton Eastern Urban Extension

Client: Mid Devon District Council

Job Number: A095750

File Origin: O:\Acoustics Air Quality and Noise\Active Projects\A095750

Document Checking:

Prepared by: Helen MakewellSenior Environmental Scientist

Initialled: HM

Checked by: Daniel ClampinSenior Environmental Consultant

Initialled: DC

Verified by: Nigel MannDirector – Environmental Scientist

Initialled: NM

Issue Date Status

1 4th May 2016 First Issue

2 11th May 2016 Assessment Update

3 11th June 2016 Further Amendments

4 11th July 2016 Amendments to Construction Traffic


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Contents Page

1.0 Introduction.......................................................................................................................1

2.0 Assessment Criteria...........................................................................................................3

3.0 Assessment Methodology..................................................................................................5

4.0 Noise Survey......................................................................................................................8

5.0 Assessment of Key Effects...............................................................................................12

6.0 Conclusions.....................................................................................................................15

Appendix Contents

Appendix A – Acoustic Terminology and Abbreviations

Appendix B – Sketches


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Executive Summary

This report presents the findings of a noise assessment for a proposed residential development in Tiverton, Devon. Noise surveys have been undertaken and the results used to determine the noise exposure of future residential dwellings associated with the development.

An indicative worst case assessment of the properties within the new development, indentifies that enhanced glazing of Rw 32 dB is required for those properties facing existing roads; with indicatively assessed areas of the development requiring an alternative means of ventilation in order to meet both ventilation and internal ambient noise criteria.

An assessment of temporary (pre site B) traffic noise effects on existing receptors along Mayfair has been undertaken. This shows that the temporary traffic noise levels on Mayfair, from the site B traffic will be around 52 to 54 dB which is significantly lower than noise levels currently experienced on Post Hill where levels are around 65 dB.


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Noise Assessment Report

1.0 Introduction

1.1 Purpose of this Report

This report presents the findings of a noise assessment for a proposed residential development in Tiverton, Devon.

A description of the existing noise environment in and around the site is provided. Noise surveys have been undertaken and the results used to verify predictions of the short-term and long-term effects of noise. The noise levels from the proposed development have been predicted at local representative receptors using CADNA noise modelling software which incorporates ISO 9613 and CRTN methodologies and calculations.

A list of acoustic terminology and abbreviations used in this report is provided in Appendix A and a set of location plans and noise contour plots relevant to the assessment are presented in Appendix B.

1.2 Legislative Context (England)

PPG24 was replaced by NPPF on 27 March 2012. With regard to noise and planning NPPF contains the following 4 short statements (section 123):

A. Avoid noise from giving rise to significant adverse impacts on health and quality of life as a result of new development;

B. Mitigate and reduce to a minimum other adverse impacts on health and quality of life arising from noise from new development, including through the use of conditions;

C. Recognise that development will often create some noise and existing businesses wanting to develop in continuance of their business should not have unreasonable restrictions put on them because of changes in nearby land uses since they were established; and

D. Identify and protect areas of tranquillity which have remained relatively undisturbed by noise and are prized for their recreational and amenity value for this reason.

The national Planning Practice Guidance (PPG) web-based resource was launched by the Department for Communities and Local Government (DCLG) on 6 March 2014 to support the National Planning Policy Framework and make it more accessible. The overall aim of the guidance, tying in with the principles of the NPPF and the Explanatory Note of the Noise Policy Statement for England, is to “identify whether the overall effect of noise exposure is, or would

Mid Devon District Council 1 A095750Tiverton Eastern Urban Extension May 2016


be, above or below the significant observed adverse effect level and the lowest observed adverse effect level for the given situation.”

A summary of the effects of noise exposure associated with both noise generating developments and noise sensitive developments is presented within the PPG: Noise and repeated as follows:

Table 1.1 Noise Exposure Hierarchy

Perception Examples of Outcomes Increasing Effect Level Action

Not noticeable No Effect No Observed Effect No Specific Measures Required

Noticeable and not intrusive

Noise can be heard, but does not cause any change in behaviour or

attitude. Can slightly affect the acoustic character of the area but not such that there is a perceived change

in the quality of life.

No Observed Adverse Effect (NOEL)

No Specific Measures Required

Lowest Observed Adverse Effect Level (LOAEL)

Noticeable and intrusive

Noise can be heard and causes small changes in behaviour and/or attitude, e.g. turning up volume of television;

speaking more loudly; closing windows for some of the time

because of the noise. Potential for non-awakening sleep disturbance.

Affects the acoustic character of the area such that there is a perceived

change in the quality of life.

Observed Adverse Effect Mitigate and reduce to a minimum

Significant Observed Adverse Effect Level (SOAEL)

Noticeable and disruptive

The noise causes a material change in behaviour and/or attitude, e.g.

having to keep windows closed most of the time, avoiding certain

activities during periods of intrusion. Potential for sleep disturbance

resulting in difficulty in getting to sleep, premature awakening and difficulty in getting back to sleep. Quality of life diminished due to

change in acoustic character of the area.

Significant Observed Adverse Effect Avoid

Noticeable and very disruptive

Extensive and regular changes in behaviour and/or an inability to

mitigate effect of noise leading to psychological stress or physiological

effects, e.g. regular sleep deprivation/awakening; loss of appetite, significant, medically

definable harm, e.g. auditory and non-auditory

Unacceptable Observed Adverse Effect Prevent

The NPPF, NSPE and PPG: Noise do not, however, present absolute noise level criteria which define SOAEL, LOAEL and NOEL which is applicable to all sources of noise in all situations. Therefore, within the context of the Proposed Development, national planning policy and appropriate guidance documents including the ‘World Health Organisation Community Noise



Guidelines’ (1999) and ‘BS 8233 – Guidance on Sound Insulation and Noise Reduction for Buildings‘ (2014), Section 2.0 presents the noise level criteria used as a basis of this assessment.

The PPG: Noise also states that “neither the NPSE nor the NPPF (which reflects the Noise Policy Statement) expects noise to be considered in isolation, separately from the economic, social and other environmental dimensions of the proposed development.”

2.0 Assessment Criteria

2.1 Internal Noise Assessment Criteria

In order to enable the assessment of the proposed development in terms of LOAEL and SOAEL, Table 2.1 presents equivalent noise levels and associated actions with the target noise level criteria identified. The noise level criteria detailed below have been derived from standards and design guidance contained within:

BS 8233:2014 ‘Guidance on sound insulation and noise reduction for buildings‘ Design Manual for Roads and Bridges Volume 11, Section 3, Part 7, HD 213/11 Revision 1, “Noise and Vibration”

Table 2.1 Noise Level Criteria and Actions Planning

Policy Guidance

Effect Level

Magnitude of

ImpactDevelopment

Receptors Noise Level Criteria Action

No Observed Adverse

Effect Level(NOAEL)

Negligible

Road Traffic Noise

Change in noise is:

< 1 dB Short Term< 3 dB Long Term

Magnitude of Change is Negligible (DMRB)

Proposed Residential Receptors

Noise levels are below:

Bedrooms – 30 dBLAeq,8hours / 45 dBLAmaxLiving Rooms – 30 dBLAeq,16hoursExternal Amenity Space – 50

dBLAeq,16hours

No Additional ActionsLevels are within BS8233 / WHO

criteria

Lowest Observed Adverse

Effect Level(LOAEL)

MinorRoad Traffic

Noise

Change in noise is:

1 ≤ 3 dB Short Term3 ≤ 5 dB Long Term

Magnitude of Change is Minor (DMRB)


Noise levels equal to or are below:


dBLAeq,16hours

No Additional ActionsLevels are within BS8233 / WHO

criteria



Planning Policy

Guidance Effect Level

Magnitude of

ImpactDevelopment

Receptors Noise Level Criteria Action

Moderate

Road Traffic Noise

Change in noise is:

3 ≤ 5 dB Short Term5 ≤ 10 dB Long Term

Magnitude of Change is Moderate (DMRB)


Noise levels exceed:

External Amenity Space – 55 dBLAeq,16hours

Reduce noise levels if possible

Levels are within BS8233 / WHO

criteria

Significant Observed Adverse Effect

(SOAEL)

High

Road Traffic Noise

Change in noise is:

5 < 10 dB Short Term10 < 15 dB Long Term

Magnitude of Change is Major (DMRB)




dBLAeq,16hours

Avoid

Unacceptable

Observed Adverse Effect

(UOAEL)

Substantial

Road Traffic Noise

Change in noise is:

≥10 dB Short Term≥15 dB Long Term

Prevent



Bedrooms – 35 dBLAeq,8hoursLiving Rooms – 40 dBLAeq,16hoursExternal Amenity Space – 60

dBLAeq,16hours

Prevent

2.2 Noise Insulation Regulations

The 1975 Noise Insulation Regulations and subsequent amendment Regulations [noise insulation (amendment) regulations 1988] provide criteria for assessing the eligibility for noise mitigation or properties based on variations in traffic noise due to a new or improved road scheme. Noise level criteria are given within the Regulations which, if satisfied, indicate whether properties in the vicinity may be entitled to the installation of additional noise insulation or to a grant to cover the cost of the noise insulation.

The entitlement conditions of the Noise Insulation Regulations are triggered when:

i. ‘the LA10 (18 hour) predicted figure is greater by at least 1 dB than the prevailing noise level’

ii. ‘the LA10 (18 hour) predicted figure is not less than the specified level (LA10 (18 hour) = 68 dB)’



iii. ‘the noise caused, or expected to be caused, by traffic using or expected to use the new highway makes an effective contribution to the LA10 (18 hour) predicted figure of at least 1 dB’



3.0 Assessment Methodology

3.1 Noise Modelling Methodology

Three dimensional noise modelling has been undertaken based on traffic data to predict LA10,

18hr noise levels at a large number of locations both horizontally and vertically. CADNA noise modelling software has been used (as shown in Figure 3.1). This model is based on the Department of Transport Calculation of Road Traffic Noise (CRTN) and ISO 9613 noise propagation methodology and allows for detailed prediction of noise levels to be undertaken for large numbers of receptor points and different noise emission scenarios both horizontally and vertically.

Figure 3.1 CADNA Noise Model

The modelling software calculates noise levels based on the emission parameters and spatial settings that are entered. Input data, assumptions and model settings as given in the table below have been used.

Table 3.1 Modelling Parameters Sources and Assumptions

Parameter Source Details

Horizontal distances – around site Ordnance Survey Ordnance Survey

Ground levels – around site Ordnance Survey Ordnance Survey

Ground levels – other areas Site Observations and Ordnance Survey

OS 1:25,000 contours and OS 1:10,000 spot heights.

Traffic data, main surrounding roads WYGE Traffic flows for local roads based on WYGE observations and experience.



Parameter Source Details

Traffic data – local roads WYGE Traffic flows for local roads based on WYGE observations and experience.

Building heights – around site WYGE Observations 8 m height for two storey residential properties, and 4 m for Bungalows

Barrier heights WYGE ObservationsAll existing barriers at 1.0 m with the exception of hedges and trees which are assumed to offer no noise protection.

Receptor positions WYGE

1 m from façade, height of 1.5 m for ground floor, 4.5 m for first floor properties with a 3m increase per storey. 1.5 m height for model grid and monitoring locations for validation.

Reflections WYGE First order reflections have been applied based on mirror image sources

Absorbent Ground CADNAFrequency dependant ground absorption has been applied based on values specified in VDI 2714/16 clause 6.3.

Façade Correction CADNA Façade corrections have been incorporated into the modelling

Gradient CADNAGradient for each road has been calculated from the height information using the ‘calc slope of roads’ tool

It is acknowledged that a number of these assumptions will affect the overall noise levels presented in this report. However, it should be noted that certain assumptions made, as identified above, are worst case.

3.2 Model Input Data

3.2.1 Traffic Noise Data

All roads expected to make a significant contribution have been included within this assessment. Noise emissions from existing traffic flows have been derived from verification of the measured noise levels along with observations made during the site survey and/or WYG Environment (WYGE) experience of similar road systems. Estimates of the vehicle speeds in the “without development” scenarios have been made based upon the speed restrictions currently in force in the area, for the “with development” scenarios a reduction in traffic speed to 15mph along Mayfair has been incorporated.

3.3 Sensitive Receptors

Table 3.4 below summarises receptor locations that have been selected to represent worst-case residential receptors with respect to direct noise from the deliveries to the retail unit. The locations of the receptors are shown on SK02 in Appendix B.



Table 3.4 Existing Receptor Locations (Construction and Operational Assessment)

Ref. Description X Co-ordinate Y Co-ordinate

R1 10 Mayfair 298629 113089R2 8 Mayfair 298656 113116R3 12 Mayfair 298632 113144R4 6 Mayfair 298657 113149R5 4 Mayfair 298662 113169R6 3 Mayfair 298627 113191R7 2 Mayfair 298647 113231R8 34 Mayfair 298612 113240R9 Corner House Post Hill 298627 113246

R10 57 Post Hill 298993 113139R11 55 Post Hill 298972 113127R12 Woodleigh House, Manley Lane 298932 113115R13 Barns Close Manley Lane 298956 113087R14 Highfield, Manley Lane 298918 113064R15 47A Post Hill 298786 113221

3.4 Tranquillity Rating

An assessment of the existing tranquillity levels of the site has been based on the mapping data published by Campaign to Protect Rural England (CPRE). This uses a colour coded system and a 500m assessment grid for the whole of England, and a tranquillity rating of between 1 and 10 is assigned (1 being least tranquil and 10 being most). By reference to these maps the development is assessed as falling into Zone 4.



4.0 Noise Survey

4.1 Noise Survey Methodology

A monitoring survey was undertaken to characterise baseline ambient noise levels currently experienced on the site and to establish the relative local background and traffic noise levels.

Equipment used during the survey included:

B&K 2238 Environmental Noise Analyser (WYG9) s/n 2684499 B&K 4231 Calibrator s/n 2176211Norsonic 140 Environmental Noise Analyser s/n 1402987Rion NL-52 Environmental Noise Analyser s/n 51043Rion NL-52 Environmental Noise Analyser (WYG23) s/n 732146Rion NL-52 Environmental Noise Analyser s/n 610201Rion NL-52 Environmental Noise Analyser (WYG20) s/n 253702Norsonic 1251 Sound Calibrator s/n 31043

The measurement equipment was checked against the appropriate calibrator at the beginning and end of the measurements, in accordance with recommended practice and no drift was observed. The accuracy of the calibrators can be traced to National Physical Laboratory Standards, calibration certificates for which are available on request.

A baseline monitoring survey was undertaken at thirteen locations (as specified in the following table and shown in SK01 of Appendix B) from Tuesday 19th January 2016 to Thursday 28th January 2016. Attended short term measurements were undertaken at seven locations during the day, evening, and night-time periods with four additional locations being measured unattended over a 215.5 hour period. The raw data collected from the long term monitoring is available upon request.

Measurements were taken in general accordance with BS 7445-1:2003 The Description and Measurement of Environmental Noise: Guide to quantities and procedures. Weather conditions during the survey period were observed as being dry with scattered showers. Anemometer readings confirmed that wind speeds were less than 5 ms-1 at all times during the survey with a predominant north easterly wind direction.

Table 4.1 Noise Monitoring Locations

Ref Description Grid ReferenceX Y

LT1 Trees to rear of 14 Uplowman Rd 298430 113624LT2 Trees to rear of Pool Anthony Dr 298154 113331LT3 W Manley Ln 298399 112546



Ref Description Grid ReferenceX Y

LT4 End of Follett Rd 297846 112214MT1 End W Manley Ln in proximity to Post Hill 298946 113107ST1 Uplowman Rd, Bridge over A361 298967 114039ST2 Uplowman Rd/Pomeroy Rd 298344 113443ST3 Hartnoll Business Centre 299090 113059ST4 W Manley Ln in close proximity to Pool Anthony Dr 297830 112831ST5 Entrance to Tidcombe Walk 297350 112681ST6 Westcott Rd 297743 112370ST7 East Manley Fruit Farm 298722 111914

CRTN1 Mayfair (off Post Hill) 298656 113200CRTN2 East Manley Fruit Farm opposite ST7 298597 111922

4.2 Noise Survey Results

Existing ambient noise levels around the site are dominated by road traffic noise generated by vehicles (including agricultural vehicles) travelling on A361, Post Hill, and HGV’s travelling to and from Hartnoll Business Park.

Ambient and background noise levels are usually described using the LAeq index (a form of energy average) and the LA90 index (i.e. the level exceeded for 90% of the measurement period) respectively. Road traffic noise is generally described using the LA10 index (i.e. the level exceeded for 10% of the measurement period).

Table 4.2. Metrological Conditions during the Survey

Survey Location/ Date & Time Temperatu

re °C Wind Speed (ms-1)

Wind Directio

n

Cloud Cover

(Oktas)Dominant Noise Source

DayST1

19/01/2016 14:33 4 2-3 E 2 Road traffic noise A361.

DayST2

19/01/2016 14:59 4 2-3 E 2 Distant road traffic noise,

occasional passing car.DayST3

19/01/2016 15:27 4 2-3 E 2 Road traffic noise Post Hill.

DayST4

19/01/2016 14:37 4 2-3 E 2

Very distant road traffic, local farm and livestock

noise.DayST5

19/01/2016 15:50 4 2-3 E 2

Distant local road traffic noise, stream, garden

maintenance.DayST6

19/01/2016 15:28 4 2-3 E 2 Pedestrian movements,

cars turning around.

DayST7

19/01/2016 15:03 4 2-3 E 2

Distant road traffic noise, local birdsong, occasional

passing traffic, loud tractor.

CRTN 1 20/01/2016 09:42 -1 1 E 1

Distant road traffic noise, occasional agricultural

vehiclesCRTN 2 20/01/2016

09:54-1 1 E 1 Distant road traffic noise,

occasional agricultural



Survey Location/ Date & Time Temperatu

re °C Wind Speed (ms-1)

Wind Directio

n

Cloud Cover

(Oktas)Dominant Noise Source

vehiclesEvening

ST119/01/2016

21:47 -4 1 NNE 0 Road traffic noise A361.Evening

ST219/01/2016

22:12 -4 1 NNE 0 Distant road traffic noise, occasional passing car.

EveningST3

19/01/2016 22:38 -4 1 NNE 0 Road traffic noise Post Hill.

EveningST4

19/01/2016 21:52 -4 1 NNE 0 Distant road traffic,

livestock.Evening

ST619/01/2015

22:43 -4 1 NNE 0 Distant road traffic.Evening

ST719/01/2016

22:20 -4 1 NNE 0 Distant road traffic, running water, wildlife.

NightST1

19/01/2016 23:54 -4 1 NNE 0 Road traffic noise A361.

NightST2

19/01/2016 23:26 -4 1 NNE 0 Distant road traffic noise,

occasional passing car.

NightST3

19/01/2016 23:00 -4 1 NNE 0 Road traffic noise on Post

Hill.NightST4

20/01/2016 00:04 -4 1 NNE 0 Distant road traffic,

livestock in barn.NightST5

19/01/2016 23:21 -4 1 NNE 0 Local road traffic, stream.

NightST6

19/01/2016 23:01 -4 1 NNE 0 Distant road traffic.

NightST7

19/01/2016 23:43 -4 1 NNE 0 Local road traffic, wildlife in

bushes.

The results of the statistical measurements and frequency measurements conducted during the survey are summarised in the following table. All values are sound pressure levels in dB (re: 2 x 10-5 Pa).

Table 4.3 Results of Baseline Noise Monitoring Survey (Average Levels)

Period Duration(T)

Monitoring Date and Times Location LAeq,T

(dB)LAmax,T(dB)

LAmin,T(dB)

LA10,T(dB)

LA90,T(dB)

Week Day07:00 - 23:00

13.5 Hours

19/01/2016 – 20/01/201607:00 – 23:00

MT150.3 81.7 30.0 46.0 41.0

Week Night23:00 – 07:00

8 Hours 19/01/2016 – 20/01/201623:00 – 07:00 38.1 71.9 26 37.5 33.1

Week Day07:00 - 23:00

96 Hours 19/01/2016 – 28/01/201607:00 - 23:00

LT1

61.6 92.3 29.9 62.7 56.5

Week Night23:00 – 07:00

56 Hours 19/01/2016 – 28/01/201623:00 - 07:00 53.1 74.6 21.9 54.8 40.1

Weekend Day

07:00 - 23:00

32 Hours 19/01/2016 – 28/01/201607:00 - 23:00 57.6 84.5 32.2 59.6 52.2

Weekend Night

23:00 – 07:00

16 Hours 19/01/2016 – 28/01/201623:00 - 07:00 51.0 73.2 23.7 54.0 36.9

Week Day07:00 - 23:00

96 Hours 19/01/2016 – 28/01/201607:00 - 23:00 LT2 56.8 95.8 26.8 57.8 49.3



Period Duration(T)


(dB)LAmax,T(dB)

LAmin,T(dB)

LA10,T(dB)

LA90,T(dB)

Week Night23:00 – 07:00

56 Hours 19/01/2016 – 28/01/201623:00 - 07:00 47.6 76.8 18 46.9 34.6

Weekend Day

07:00 - 23:00

32 Hours 19/01/2016 – 28/01/201607:00 - 23:00 55.0 95.5 30.2 54.9 42.7

Weekend Night

23:00 – 07:00

16 Hours 19/01/2016 – 28/01/201623:00 - 07:00 46.0 70.5 23.4 47.7 33.9

Week Day07:00 - 23:00

96 Hours 19/01/2016 – 28/01/201607:00 - 23:00

LT3

52.8 98.7 21.9 47.5 38.6

Week Night23:00 – 07:00

56 Hours 19/01/2016 – 28/01/201623:00 - 07:00 42.8 81.0 23.0 38.3 32.6

Weekend Day

07:00 - 23:00

32 Hours 19/01/2016 – 28/01/201607:00 - 23:00 50.6 89.4 25.3 45.7 34.2

Weekend Night

23:00 – 07:00

16 Hours 19/01/2016 – 28/01/201623:00 - 07:00 31.8 58.8 23.7 32.1 28.1

Week Day07:00 - 23:00

96 Hours 19/01/2016 – 28/01/201607:00 - 23:00

LT4

51.8 90.8 28.6 48.3 40.2

Week Night23:00 – 07:00

56 Hours 19/01/2016 – 28/01/201623:00 - 07:00 42.7 90.8 27.6 39.4 34.4

Weekend Day

07:00 - 23:00

32 Hours 19/01/2016 – 28/01/201607:00 - 23:00 50.3 86.9 29.7 48.0 37.9

Weekend Night

23:00 – 07:00

16 Hours 19/01/2016 – 28/01/201623:00 - 07:00 35.2 63.6 28.7 35.9 31.8

Day07:00 - 19:00

15 Mins 19/01/2016 14:33 ST1 75.2 86.7 49.2 78.9 67.115 Mins 19/01/2016 14:59 ST2 59.4 83.9 38.9 55.5 45.115 Mins 19/01/2016 15:27 ST3 62.3 83.8 40.7 59.3 43.815 Mins 19/01/2016 14:37 ST4 50.8 74.4 29.8 48.3 32.215 Mins 19/01/2016 15:50 ST5 60.2 79.0 43.8 64.1 46.515 Mins 19/01/2016 15:28 ST6 42.9 60.2 34.6 43.5 36.415 Mins 19/01/2016 15:03 ST7 59.9 84.5 31.6 56.8 34.23 Hours 20/01/2016 09:42 CRTN 1 58.5 93.3 30.7 53.9 36.9

3 Hours 20/01/2016 09:54 CRTN 2 49.5 77.2 34.4 50.6 39.4

Evening19:00 - 23:00

15 Mins 19/01/2016 21:47 ST1 70.3 85 43.7 74.2 54.615 Mins 19/01/2016 22:12 ST2 51.1 75.5 37.4 47.9 40.615 Mins 19/01/2016 22:38 ST3 53.9 75.2 30.7 56.3 35.115 Mins 19/01/2016 21:52 ST4 34.8 65.2 27.9 36.2 31.315 Mins 19/01/2015 22:43 ST6 37.9 68.2 29.5 39.8 33.0

19/01/2016 22:20 ST7 34.2 67.5 29.8 35.4 30.8Night

23:00 - 07:00

15 Mins 19/01/2016 23:54 ST1 64.5 82.2 33.7 67.3 40.315 Mins 19/01/2016 23:26 ST2 48.6 73.8 33.2 47.5 37.7



Period Duration(T)


(dB)LAmax,T(dB)

LAmin,T(dB)

LA10,T(dB)

LA90,T(dB)

15 Mins 19/01/2016 23:00 ST3 48.5 69.8 28.2 50.1 32.815 Mins 20/01/2016 00:04 ST4 32.3 57.9 24.1 34.6 25.915 Mins 19/01/2016 23:21 ST5 46.5 65.4 39.4 44.1 40.515 Mins 19/01/2016 23:01 ST6 35.9 63.0 30.1 38.5 31.815 Mins 19/01/2016 23:43 ST7 35.9 70.3 28.9 34.6 30.0

All values are sound pressure levels in dB re: 2x 10-5 Pa



5.0 Assessment of Key Effects

5.1 Construction Traffic Noise

Throughout the construction phase of Site B the development will generate traffic associated with the transportation of construction plant and materials to and from the Site. It is likely that these operations will involve the use of heavy goods vehicles (HGV’s). In addition, traffic will be generated by the transportation of construction staff to and from the site.

It should be noted that any impacts from construction traffic are temporary in nature and will only last for the duration of the construction works. In addition, construction traffic generation is unlikely to be constant for the whole duration of the contract, with peak traffic flows usually occurring during the early stages when relevant plant is being imported and infrastructure material deliveries are typically greatest, tapering off as internal fitting and finishing operations are undertaken.

As detailed in the transportation assessment, a Construction Traffic Management Plan will need to be developed in order to minimise conflict between existing road users, future residents of Site B and construction traffic.

As the document will help to control the levels of construction traffic moving in and out of the site and the times they will do so, it will also help control noise levels from the additional traffic moving on to and off of the site. More information regarding this can be found in the transport assessment associated with this development.

5.2 Operational Traffic Noise

5.2.1 DMRB Noise Change Assessment

The table below shows the results of the traffic noise assessment comparing the ‘with’ and ‘without’ development traffic noise levels for the first and last phases of the proposed development. A visual representation is shown in SK03 and SK04.

It should be noted however that the access to site B, as modelled in this assessment, will only be for the first five years. After this time, access to site B will be from a purpose built junction on Post Hill and via Site A. The noise levels will subsequently reduce at the identified receivers.

Scenario 1a is defined as the traffic noise with 300 houses within the proposed development with all traffic entering and exiting the site via Mayfair



Scenario 1b is defined as the traffic noise with 300 houses within the proposed development with traffic entering site via Manley Lane and exiting site via Mayfair.

Scenario 2 (shown on Table 5.3) is defined as the traffic noise with 475 houses within the proposed development with all traffic entering and exiting the site via Mayfair

Scenario 3a is defined as the traffic noise with 500 houses within the proposed development with all traffic entering and exiting the site via Mayfair

Scenario 3b is defined as the traffic noise with 500 houses within the proposed development with traffic entering site via Manley Lane and exiting site via Mayfair.

Table 5.1 Difference Between With and Without Scenarios (One Way Traffic (Mayfair))

Location

Scenario 1A Scenario 3A

Traffic NoiseWithout

Development 2026(LA10,18hr dB(A))

Traffic NoiseWith

Development Only 2026

(LA10,18hr dB(A))

Scenario 1

Difference between with and without development

scenarios(dB(A))


Development 2026

(LA10,18hr dB(A))

Traffic NoiseWith


(LA10,18hr dB(A))

Scenario 2


scenarios(dB(A))

10 Mayfair 46.8 53.7 6.9 46.8 56.0 9.28 Mayfair 48.1 55.7 7.6 48.1 57.9 9.812 Mayfair 47.9 54.3 6.4 47.9 56.5 8.66 Mayfair 47.0 54.4 7.4 47.0 56.8 9.84 Mayfair 43.9 51.7 7.8 43.9 53.9 10.03 Mayfair 46.1 52.3 6.2 46.1 54.5 8.42 Mayfair 49.9 56.3 6.4 49.9 58.8 8.934 Mayfair 51.6 52.5 0.9 51.6 53.0 1.4

Corner House Post Hill 58.1 59.2 1.1 58.1 60.0 1.9

57 Post Hill 62.8 62.8 0.0 62.8 62.9 0.155 Post Hill 56.6 56.7 0.1 56.6 56.8 0.2Woodleigh

House, Manley Lane 54.3 54.4 0.1 54.3 54.5 0.2

Barns Close Manley Lane 52.4 52.5 0.1 52.4 52.5 0.1

Highfield, Manley Lane 50.2 50.2 0.0 50.2 50.3 0.1

R1547A Post Hill

65.5 65.9 0.4 65.5 66.1 0.6

Table 5.2 Difference Between With and Without Scenarios (Two Way Traffic)



Location

Scenario 1B Scenario 3B


Development 2026(LA10,18hr dB(A))

Traffic NoiseWith


(LA10,18hr dB(A))

Scenario 1


scenarios(dB(A))


Development 2026

(LA10,18hr dB(A))

Traffic NoiseWith


(LA10,18hr dB(A))

Scenario 2


scenarios(dB(A))

10 Mayfair 46.8 51.3 4.5 46.8 53.6 6.88 Mayfair 48.2 53.3 5.1 48.2 55.8 7.612 Mayfair 48.0 52.2 4.2 48.0 54.5 6.56 Mayfair 47.0 51.8 4.8 47.0 54.2 7.24 Mayfair 44.4 49.3 4.9 43.8 51.5 7.73 Mayfair 46.0 50.2 4.2 46.0 52.5 6.52 Mayfair 49.9 53.7 3.8 49.9 56.2 6.334 Mayfair 51.6 52.4 0.8 51.6 53.0 1.4

Corner House Post Hill 58.1 58.9 0.8 58.1 59.6 1.5

57 Post Hill 62.8 63.3 0.5 62.8 64.0 1.255 Post Hill 56.9 60.1 3.2 56.9 64.4 7.5Woodleigh

House, Manley Lane 54.9 59.6 4.7 54.9 64.6 9.7

Barns Close Manley Lane 53.4 59.5 6.1 53.4 65.5 12.1

Highfield, Manley Lane 51.3 57.8 6.5 51.3 63.0 11.7

R1547A Post Hill

65.2 65.6 0.4 65.2 65.7 0.5

Table 5.3 Difference Between With and Without Scenarios (Two Way Traffic)

Location

Scenario 2

Traffic NoiseWithout Development 2026

(LA10,18hr dB(A))

Traffic NoiseWith Development Only

2026(LA10,18hr dB(A))


scenarios(dB(A))

10 Mayfair 46.8 55.7 8.98 Mayfair 48.1 57.7 9.6

12 Mayfair 47.9 56.2 8.36 Mayfair 47.0 56.5 9.54 Mayfair 43.9 53.6 9.73 Mayfair 46.1 54.2 8.12 Mayfair 49.9 58.5 8.6

34 Mayfair 51.6 52.9 1.3Corner House

Post Hill 58.1 59.9 1.8



Location

Scenario 2

Traffic NoiseWithout Development 2026

(LA10,18hr dB(A))

Traffic NoiseWith Development Only

2026(LA10,18hr dB(A))


scenarios(dB(A))

57 Post Hill 62.8 62.9 0.155 Post Hill 56.6 56.8 0.2Woodleigh

House, Manley Lane 54.3 54.5 0.2

Barns Close Manley Lane 52.4 52.5 0.1

Highfield, Manley Lane 50.2 50.3 0.1

R1547A Post Hill 65.5 65.7 0.2

The assessments in Tables 5.1 to 5.3 above show a worst case scenario with the highest predicted traffic flows in the first five years. The levels of change indicated in Tables 5.1 to Table 5.3 are expected when there are large increases in traffic flows on previously low flow roads.

Additionally the assessment indicates that for the temporary period during the introduction of 300 properties on site B there are impacts where the noise level change is greater than 5 dB but less than 10 dB at properties along Mayfair in both the one way and two way assessments and along Manley Lane for the one way assessment. This is also true for the development of 475 properties on site B with two way access via Mayfair.

During the temporary period the introduction of 500 properties on Site B, the one way traffic route indicates noise change impacts for properties along Mayfair of greater than 5 dB and but less than 10 dB, however noise change impacts greater than 10 dB along Manley Lane. The two way traffic route indicates noise change levels for properties along Mayfair of up to 10 dB. Given that the one way traffic scenario with 500 properties exceeds 12 dB along Manley lane, this route is not being considered further.

Table 5.4 below summarises the assessment findings under the different scenarios

Table 5.4 Summary of Traffic Impacts



Mayfair (2-Way) Mayfair (1-Way) Manley Lane (1-Way)300

PropertiesScenario 1A

>5dB - <10dBScenario 1B

>5dB - <10dBScenario 1B>5dB - <10d

475 Properties

Scenario 2>5dB - <10dB

Not Assessed Not Assessed

500 Properties

Scenario 3A>=10dB

Scenario 3B>5dB - <10dB

Scenario 3B>10dB

It should be noted however that the access to site B, as modelled in this assessment, will only be for the first five years. After this time, access to site B will be from a purpose built junction on Post Hill and via Site A. The noise levels will subsequently reduce at the identified receivers.

In respect to external areas, additional predictions of the noise level changes indicate that the noise level in the gardens of the identified receivers will not exceed 55dB LAeq,16h where they did not do so already.

In respect to the Noise Insulation Regulations, none of the residential receptors have exceeded 68dB LA10,18h and so based on the predicted traffic flows the findings of this assessment indicate no eligibility under these regulations.

5.2.2 Noise Intrusion LAeq Daytime and Night-Time and LAmax Glazing Requirements

Internal noise levels, at two indicative locations along the Site B boundary assuming worst case use, based on the existing ambient noise climate, have been assessed both with windows open, where a reduction from a partially open window of 10 dB has been used, and with windows closed where an assumption of a glazing with a sound reduction of 30 dB has been used unless stated otherwise.

Where the relevant internal ambient noise level criteria are not met with standard double glazing (sound reduction 30 dB) then higher glazing specifications have been provided (bold text) accordingly in Table 5.3.

The glazing and ventilation strategy has been designed to achieve WHO/BS 8233 internal LAeq

daytime noise level criteria of 35 dB and internal night-time LAeq noise level criteria (30 dB) with windows closed within residential spaces. The glazing specifications would also meet the LAmax criteria of 45 dB with windows closed.

Table 5.3 Noise Intrusion Levels LAeq and LAmax



Location Room Type Daytime External LAeq

Night-TimeExternal LAeq

External LAmax

Glazing Specification

(SRI) to Achieve 35 dB LAeq day, 30 dB LAeq night and LAmax 45

dB

Alternative Ventilation Required?

Facing Post Hill Bedroom 56.8 47.6 76.8 32.0 YesFacing Manley

Lane Bedroom 50.3 38.1 71.9 30.0 Yes

Within the new development bedrooms/living spaces with windows facing Mayfair, Post Hill and Manley Lane will require improved glazing and all areas require an alternative means of ventilation in order to meet both ventilation and internal ambient noise criteria. Alternative ventilation can be provided in several ways from acoustic trickle vents (which need to have the same acoustic performance as the glazing), wall vents or other passive ventilation systems or mechanical ventilations systems.

5.3 Tranquillity Assessment

An assessment of the existing tranquillity levels of the site has been based on the mapping data published by Campaign to Protect Rural England (CPRE). This uses a colour coded system and a 500m assessment grid for the whole of England, and a tranquillity rating of between 1 and 10 is assigned (1 being least tranquil and 10 being most). By reference to these maps the development is assessed as falling into Zone 4.

There is currently no public access across the site and considering the residential nature of the development and its proximity to existing residential areas immediately adjacent to the site, the area could therefore be considered to be of less tranquillity value than the mixed woodland to the north of the site or the Grand Western Canal Country Park to the south. Therefore the proposed development is considered to have a negligible effect on local access to areas of tranquillity.



6.0 Conclusions

NPPF 123 A & B

In considering the NPPF test in section 123, points A & B, the proposed development is not expected to have an ‘adverse impact’ on health or quality of life. Similarly, with regard to NPPF (123) point B, it is considered that all ‘adverse impacts on health and quality of life’ (relating to noise) are mitigated by the use of the following mitigation.

An assessment of external noise levels from changes to road traffic flows as a result of the development of Site B, has shown that noise levels (including the effects of reducing the speeds to 15mph) are not predicted to be above the Lowest Observed Adverse Effect Level (LOAEL) criteria at properties along Mayfair. Furthermore the worst case assessment shows that the temporary traffic noise levels on Mayfair, from the site B traffic will be around 52 to 54 dB which is significantly lower than noise levels currently experienced on Post Hill where levels are around 65 dB.

Therefore, the proposed development is unlikely to have ‘significant adverse impact’ on health, amenity or quality of life at certain receptors.

Assessment of external noise levels from the changes to road traffic flows has shown that noise levels in proposed gardens (external amenity areas) will not exceed LOAEL where they did not do so previously.

Glazing and Ventilation Strategy

A glazing and ventilation strategy has been provided for the proposed dwellings which achieves both ventilation and internal ambient noise level requirements of LAeq daytime 35 dB, LAeq

night-time of 30 dB and LAmax night-time of 45 dB in all residential bedroom/spaces of the proposed development. The suggested glazing specifications are understood to achievable.

NPPF 123 C & D

The development is situated in a CPRE Zone 4 area of tranquillity (Zone 10 being the most tranquil and Zone 1 being the least tranquil), as such NPPF 123 point D is not considered to apply to this site.

Planning Practice Guidance

It is considered that the noise mitigation in section 5.1 of this report is sufficient to reduce the effects of any noticeable and disruptive noise being currently emitted from the surrounding



environment by helping to prevent noise levels exceeding the BS 8233 criteria for daytime LAeq within all areas of the proposed development.



Appendices

Mid Devon District Council A095750Tiverton Eastern Urban Extension May 2016


Appendix A – Acoustic Terminology and Abbreviations

Acoustic Terminology

dB Sound levels from any source can be measured in frequency bands in order to provide detailed information about the spectral content of the noise, i.e. whether it is high-pitched, low-pitched, or with no distinct tonal character. These measurements are usually undertaken in octave or third octave frequency bands. If these values are summed logarithmically, a single dB figure is obtained. This is usually not very helpful as it simply describes the total amount of acoustic energy measured and does not take any account of the ear’s ability to hear certain frequencies more readily than others.

dB(A) Instead, the dBA figure is used, as this is found to relate better to the loudness of the sound heard. The dBA figure is obtained by subtracting an appropriate correction, which represents the variation in the ear’s ability to hear different frequencies, from the individual octave or third octave band values, before summing them logarithmically. As a result the single dBA value provides a good representation of how loud a sound is.

LAeq Since almost all sounds vary or fluctuate with time it is helpful, instead of having an instantaneous value to describe the noise event, to have an average of the total acoustic energy experienced over its duration. The LAeq, 07:00 – 23:00 for example, describes the equivalent continuous noise level over the 12 hour period between 7 am and 11 pm. During this time period the LpA at any particular time is likely to have been either greater or lower that the LAeq, 07:00 – 23:00.

LAmin The LAmin is the quietest instantaneous noise level. This is usually the quietest 125 milliseconds measured during any given period of time.

LAmax The LAmax is the loudest instantaneous noise level. This is usually the loudest 125 milliseconds measured during any given period of time.

Ln Another method of describing, with a single value, a noise level which varies over a given time period is, instead of considering the average amount of acoustic energy, to consider the length of time for which a particular noise level is exceeded. If a level of x dBA is exceeded for say. 6 minutes within one hour, then that level can be described as being exceeded for 10% of the total measurement period. This is denoted as the LA10, 1 hr = x dB.

The LA10 index is often used in the description of road traffic noise, whilst the LA90, the noise level exceeded for 90% of the measurement period, is the usual descriptor for underlying background noise. LA1 and LAmax are common descriptors of construction noise.



Rw The weighted sound reduction index determined using the above measurement procedure, but weighted in accordance with the procedures set down in BS EN ISO 717-1. Partitioning and building board manufacturers commonly use this index to describe the inherent sound insulation performance of their products.

Abbreviations

CADNA – Computer Aided Noise Abatement

DMRB – Design Manual for Roads and Bridges

HGV – Heavy Goods Vehicle

PPG – Planning Practice Guidance

UDP – Unitary Development Plan

UKAS – United Kingdom Accreditation Service

WYGE – WYG Environment



Appendix B – Sketches

SK01 Noise Monitoring Locations

SK02 Existing Receptor Locations

SK03 Existing Daytime LA10,18hr

SK04 Final Phase Daytime LA10,18hr

SK05 68dB Contour - Final Phase Daytime LA10,18hr


1 · web viewan indicative worst case assessment of the properties within the new development,...

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