Aberdeen agglomeration: noise action plan

5. Identification of Management Areas

1.9 Need to identify Management Areas

Production of the strategic noise maps is only the first step in the process of 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.

1.10 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 55 dB 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 Aberdeen 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 Aberdeen agglomeration a minimum of 4100 people are housed within the road CNMA approximate areas and a minimum of 600 people are housed within the rail CNMA approximate areas.

1.11 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 Aberdeen agglomeration are shown in Appendix 2. These CQAs were obtained from national data sets and maps and local knowledge will be used to identify and assess any other potential CQAs during the consultation process.

1.12 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 it 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.

Table 3 - Preliminary actions as part of planning process

Preliminary Actions	Anticipated Completion Date
Assess all CNMA's as set out in the previously published guidance10	20th April 2014
Assess all CQA's as set out in the previously published guidance14	20th April 2014

1.13 Noise Mitigation Measures

A number of road infrastructure developments are programmed over the next 5 years that will reduce noise levels across the CNMAs.

The most significant of these is the Aberdeen Western Peripheral Route ( AWPR) which will provide a link from the north to the south enabling traffic to bypass Aberdeen. Benefits will be most apparent on Anderson Drive and Auchmill Road where the traffic flow is predicted to reduce by 5-10%, with associated reduction in noise levels. Traffic flows will also reduce on the majority of the other CNMAs. Preparation works commenced in 2013 and completion of the AWPR is predicted by 2018.

A Third Crossing over the River Don is also a major development that will provide a new route to reduce congestion at the existing 2 crossings over the River. The Crossing will particularly reduce the traffic flow on parts of King Street, parts of Great Northern Road and Auchmill Road, again with an anticipated noise reduction in the CNMAs in these areas. Construction is due to commence in 2014 for a late 2015 opening.

Other road infrastructure measures with the potential to reduce noise levels in the CNMAs include improvements to Haudagain roundabout on the North Anderson Dr/Auchmill Road corridor, the Berryden corridor, South College Street and the partial pedestrianisation of Union St.

Similarly, the Council commenced the development of a Strategic Urban Mobility Plan ( SUMP) for the City Centre during 2012. A SUMP is essentially a transport masterplan looking at the way people move around by different modes of transport. These include walking, cycling, bus, train, taxi, motorcycle, car, van and HGVs. The SUMP vision is to create a vibrant, attractive, connected and economically sustainable city centre that is accessible to all and well equipped to adapt to changing circumstances over time. Footfalls studies, on street interviews, on-line questionnaire and 4 stakeholder workshops were all used to engage and consult with the public and other stakeholders. Aberdeen received a E10,000 EU award in recognition of excellence in the development of the SUMP. The Plan will be further developed in 2014 and, when implemented, has the potential to reduce noise levels in the City Centre CNMAs.

Potential additional noise mitigations measures will be considered between 2013 and 2018.

1.14 Aberdeen Agglomeration proposed noise actions between 2013 and 2018

Noise action options fall into five categories, as outlined in Table 4. 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.

Table 4 - Remedial Actions

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

Aberdeen NAP objectives, actions (falling within the above categories), timescales and cross-linkages to other Noise Action Plans in Scotland are outlined in Table 5. It is estimated that within the Aberdeen agglomeration a minimum of 4100 people are housed within the road CNMA approximate areas and a minimum of 600 people are housed within the rail CNMA approximate areas.

Table 5 - Transportation (within Aberdeen agglomeration) noise mitigation between 2013 and 2018

No	Action
		'13	'14	'15	'16	'17	'18
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.
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
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
4a	Provide guidance, information and progress updates on the Aberdeen 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 traffic models where feasible