Glasgow agglomeration: noise action plan

5. Identification of Management Areas

5.1 Need to identify Management Areas

Production of the strategic noise maps is only the first step in the process in the management of environmental noise. The Directive is clear that Member States should aim to " avoid, prevent or reduce on a prioritised basis the harmful effects, including annoyance, due to exposure to environmental noise". In Scotland, specific steps have been taken in order to use the noise maps as a basis for identifying and focusing on those areas where people are most likely to be annoyed by noise. These are referred to as Noise Management Areas ( NMAs). It is such areas that are largely intended to form the basis of associated Action Plans. The process of agreeing NMAs involves various steps including provisional assignment as a Candidate Noise Management Area ( CNMA).

The Directive is also clear that Member States should aim to identify and preserve its Quiet Areas. Hence a similar process is followed whereby noise mapping can be used to identify Candidate Quiet Areas with a subsequent process leading to agreement of actual Quiet Areas.

5.2 Process of Identification of Noise Management and Quiet Areas - Prioritisation Matrix

There are no noise limits values or noise thresholds in place in Scotland as it is recognised that analysing the noise contours alone will not necessarily identify areas suffering from the greatest noise impact. In order to gain a better understanding of the potential noise impacts it is helpful to identify those areas where high population density comes together with high levels of noise. The means of achieving this has emerged using a specially developed prioritisation matrix which operates by assigning a numerical value to buildings and road/rail segments within the relevant areas. ^[9]

The objective of the prioritisation matrix is to identify areas where people living within these areas are most likely to be annoyed by noise from either road or railway traffic noise sources. The identification of such areas has been based on a scoring system which takes into account the number of people potentially affected, and the annoyance response to the particular noise source under consideration (either rail or road).

From initial analysis of the noise maps, the prioritisation process is a method of determining 'Candidate Noise Management Areas' ( CNMAs) and thereafter 'Noise Management Areas' ( NMAs). Figure 2 outlines the step-by-step journey of the prioritisation process.

Figure 2 Step by step stages of the Prioritisation Process. BPS = Building Prioritisation Score; SPS = Source Prioritisation Score (see below for more detail)

A prioritisation matrix is generated from a computer based model, where each building is assigned a Building Prioritisation Score ( BPS), which takes into account the predicted road and rail noise levels, in conjunction with the number of people potentially affected and the annoyance response of that exposed population relative to the transportation noise source in question. A Source Prioritisation Score ( SPS) is then determined by first segmenting the road or rail corridors into 100m sections. Each road/rail segment is then given a unique ID and for each building with a noise level greater than or equal to L _den 55dB the ID of the road/rail segment that is closest to it is assigned to that building. The logarithmic sum of BPS values for all buildings with the same nearest road/rail segment ID is then assigned to the relevant road segment to give the Source Prioritisation Score for that road/rail segment.

All SPS values are ranked, where the top 1% of SPSs (normally distributed) corresponded to the mean SPS plus two standard deviations, to identify the highest three 1% bands of the SPS scores across the road and railway network. These are subsequently referred to as Candidate Noise Management Areas ( CNMAs). Determination of a CNMA is simply a means of highlighting that a geographical area should be considered further in terms of a potential need for noise management. It may be that following further analysis, the area will be disregarded entirely or extended or reduced. Ultimately, the decision about whether or not a CNMA is eventually assigned full Noise Management Area ( NMA) status is dependent on a series of steps during which various assessments and considerations are taken into account. These are outlined in separate Technical Guidance ^[10] .

The areas with CNMA status within the Glasgow agglomeration are shown in Appendix 1. The CNMA to NMA review process will, amongst other steps, verify the noise model findings and assumptions in comparison to physical features which are evident on the transport network. The assigning of Noise Management Areas and subsequent appraisal, planning, and prioritisation of potential mitigation measures in the NMAs form a core part of the Action Planning Process.

It is estimated that within the Glasgow agglomeration a minimum of 30,144 people are housed within the road CNMA approximate areas and a minimum of 3,924 people are housed within the rail CNMA approximate areas.

5.3 Identification of Candidate Quiet Areas

The END recognises the importance of the preservation of existing quiet areas. Access to quiet areas and peaceful soundscapes is generally known to bring about a range of benefits to human health and well being. ^{[11] [12]} 'Quiet Areas' are not specifically defined in the Directive, rather they are recognised as areas to be determined by the Member State and which are subject to noise falling beneath a limit value set by the Member State.

With that in mind, a study by the Transport and Research Laboratory ( TRL) ^[13] was used as a basis for identification of 'Quiet Areas' in Scotland. It was decided by SENSG that Quiet Areas should be defined as areas which are a minimum of 9 hectares and in which at least 75% of the area is subject to noise levels not exceeding < 55 dB L _day. In addition, for the second round of mapping SENSG decided that any local authority within an agglomeration boundary can, with good and justifiable reasons, request that an area be classified as a Quiet Area.

In addition to identifying candidate noise management areas (described above), the strategic noise mapping exercise can also be used to identify Candidate Quiet Areas ( CQAs). As with the CNMA process, there are a series of steps to be taken to determine which of the CQAs will fully progress to actual Quiet Area status. This is covered in separate Technical Guidance ^[14] . The areas with CQA status within the Glasgow agglomeration are shown in Appendix 2.

5.4 Action Planning

The Directive requires that action plans are produced for each of the qualifying agglomerations, major airports and major transport systems. The content of the Action Plans are however for member states to determine but based on some minimum requirements as set out in Annex 5 of the Directive. This action plan document provides the basic outline of how we intend to manage noise and preserve quiet areas. On that basis, action plans are largely focused on taking forward the candidate noise management areas and quiet areas identified by the strategic noise mapping and prioritisation exercises described previously.

Scotland's Greenspace Map http://www.greenspacescotland.org.uk/scotlands-greenspace-map.aspx is a world first; no other country has mapped its greenspace in this way. This interactive map provides information about the type and extent of greenspace in urban Scotland ( i.e. towns and cities with a population of over 3000). It was compiled in 2011 from greenspace data provided by the 32 Scottish Councils. Although Greenspace Map does not directly use the term quiet does embrace the concept of passive recreation and breathing spaces which are defined as an oasis of calm amongst city bustle. Defining Quiet Areas as part of the Action Planning process can be seen as an extension of that work.

The preliminary actions to be undertaken as part the action planning process are set out in Table 3 below. Further detail on proposed noise actions can be found in sections 5.5 and 5.6

Preliminary Actions	Anticipated Completion Date
Assess all CNMA's as set out in the previously published guidance [10]	20th April 2014
Assess all CQA's as set out in the previously published guidance [14]	20th April 2014

Table 3 - Preliminary actions as part of planning process

5.5 Glasgow Agglomeration noise actions up to 2012

A number noise management measures and outcomes have been achieved in Scotland since the first Glasgow NAP was published, as detailed in Table 4.

Options
A review of current research on road surface reduction techniques. This research commissioned by the Scottish Government comments on applicability for Scotland The report can be found here.
We have updated planning advice to local authorities see PAN 1/2011
We have pressed the European Commission(through Defra) for quieter vehicle requirements e.g. quieter tyres and quieter vehicles
A review of Air Quality Guidance to take account of noise is due to commence this year.
We have asked Defra to carry out further annoyance research on a UK basis and this is now included in the research programme.
Use of low noise road surfacing on the roads within agglomerations where appropriate (and where benefits can be demonstrated) and the inclusion of this specification within tenders
Noise barrier installation considered for developments alongside busy road/rail routes where appropriate
Promoting the use of [low carbon] electric cars and City Car Clubs
Inclusion of Noise Management Areas and Quiet Areas within local authority development control (planning) process

Table 4 - Examples of noise mitigation between 2006 and 2012

5.6 Glasgow Agglomeration proposed noise actions between 2013 to 2018

Noise action options fall into five categories, as outlined in Table 5. The potential remedial actions will be the subject of a cost benefit analysis. Consideration will also be given to who would be responsible for any proposed actions and whether or not they are affordable or desirable.

Category	Options
1	Maintenance and improvement works where appropriate
2	Network operational management of roads within agglomerations where appropriate
3	Development Proposals and Policies where appropriate
4	Desktop: Research, appraisal and evaluation where appropriate
5	Communications and stakeholder engagement where appropriate

Table 5 - Remedial Actions

Glasgow NAP objectives, actions (falling within the above categories), timescales and cross-linkages to other Noise Action Plans in Scotland are outlined in Table 6.

No	Action	Timescale
		'12	'13	'14	'15	'16	'17	'18
Objective 1 - On a prioritised basis, by 2018 we aim to reduce the exposure to environmental noise in NMAs
1a	Develop and apply appropriate Appraisal and Test of Reasonableness tools through SENSG, including cost benefit analysis, to rank effective NMA interventions.
1b	Where appropriate apply noise management interventions on a prioritised basis during existing maintenance and improvement programmes where reasonably practicable.
1c	Engage with Transportation Working Group to assess trunk road and rail NMAs within agglomerations.
Objective 2 - By 2018, we will incorporate environmental noise management within all stages of the planning process including transportation planning, design, construction and maintenance activities as appropriate
2a	Consider incorporating a commitment to mitigate environmental noise emissions into future corporate and/or annual service plans
2b	Incorporate consideration of noise issues into future construction or maintenance contracts, franchise agreements and specifications.
2c	Conduct before-and-after sample noise measurement, where possible, to (i) determine measured baseline at selected NMAs prior to mitigation construction and (ii) appraise noise mitigation approaches in terms of cost benefit and delivery of effective noise reduction.
2d	Consideration to be given to post evaluation of completed mitigation measures specified within planning conditions where appropriate
Objective 3 - By 2018, we will endeavour to demonstrate a practical contribution to noise reduction via existing and future proposals and policies
3a	Transport and travel policies and proposals to both take into account and facilitate noise management.
3b	Consider promoting Intelligent Transport Systems to better manage road flows.
3c	Consider promoting uptake of low noise tyres where appropriate through SENSG
3d	Support for an update to Noise Insulation Scotland Regulations ( NISR) legislation
Objective 4 - By 2018, we will promote channels of communication to stakeholders that encourage a learning environment
4a	Provide guidance, information and progress updates on the Glasgow NAP actions to the Scottish Noise Mapping Website
4b	Conduct review of noise complaints on road network over the last 5 years in order to better understand their nature.
4c	Incorporate noise maps into appropriate local authority models

Table 6 - Transportation (within Glasgow agglomeration) noise mitigation between 2012 and 2018