Scottish Government

4 Action Planning Process

4.1 Key Stages

The Action Planning process comprises five key stages as shown in the Table 4 below.

Table 4 Key stages of the Action Planning process

Stages 1 and 2 of the Action Planning Process (Table 4 above) are complete and are described in earlier sections of this document. Stage 3, is also complete, and is the Prioritisation Process described in sections 4.2 to 4.4 following. Stages 4 and 5, which are described in this section of the document will be conducted as part of the first round Action Planning process, and will be informed by consultation on this draft Plan.

4.2 Prioritisation

Whilst noise maps presented in the Scottish Government Scottish Noise Mapping website present the information from the first round noise mapping exercise in terms of 5dB noise contours, it is not practical to use these contour maps alone to determine where the highest noise levels correlate with exposure of residential buildings. Furthermore an examination of the consolidated maps does not reveal sufficient information regarding the specific noise source (road, rail or industrial) affecting noise sensitive properties.

Article 1 of the END states the following.

"The aim of this Directive shall be to define a common approach intended to avoid, prevent or reduce on a prioritised basis the harmful effects, including annoyance, due to exposure to environmental noise."

A process for complying with Article 1 of the END was therefore required. This process is the prioritisation process described in Section 4.3 following. The process is a method of determining areas where the predicted road and rail noise levels are likely to cause most annoyance to people potentially affected.

4.3 Development of the Prioritisation Process

The purpose of prioritisation is to establish those locations within the area described in Section 2.5 where people are most likely to be annoyed by noise and that may require noise intervention or management, and to determine the order and process of this intervention or management in line with the aim of Article 1 of the END as reproduced in Section 4.2 above.

The prioritisation evaluates strategic noise levels within the first round noise maps, in terms of the road, railway, and aircraft source areas most likely to cause annoyance to people potentially affected. This will enable appropriate actions to be determined on the basis of a consideration of noise levels, the number of people potentially affected, and the annoyance response to road, railway, and aircraft noise.

The prioritisation process has been undertaken through a noise assessment process known as a Prioritisation Matrix. The matrix has been developed in a transparent and consistent manner to inform all of the action plans being progressed and uses a computer based noise model to analyse the data. Although the matrix provides a focus for action planning, due to the strategic nature of the mapping, a check on the strategic noise levels, the matrix input data and any proposed interventions will be essential prior to the implementation of any suggested actions. This check will be undertaken as an early measure in the action planning process (see Section 4.5).

The Prioritisation Matrix for the transportation plan has involved segmenting of the road and rail corridors identified from the round one noise mapping ( Appendix 1) into 100m sections. Using the noise mapping information, each building within each segment was assigned a score based on the predicted noise level, the number of people living in that building and the annoyance response. These scores are known as the Building Prioritisation Scores ( BPSs). Each building (with its associated BPS) is then assigned by the noise model to its nearest source of road or rail noise and for each 100m section of road or rail the assigned BPS scores are logarithmically summed to give a resultant Source Prioritisation Score ( SPS).

All SPS values are then prioritised in a manageable list for consideration in the action planning process. Whilst it is clearly desirable to start with the areas with the highest SPS the question of " how high does the SPS have to be before consideration is given in the first round of actions?" arose. Therefore a basic statistical analysis of the SPSs was undertaken and it was found that the top one percent of SPSs (normally distributed) corresponded to the mean SPS plus two standard deviations. Following consultation with all END working groups it was decided to identify the top three percent of the road and railway network assessed in terms of the highest three one percent bands of the SPS scores. The top one percent were then colour coded red, the next one percent colour coded amber, the next one percent colour coded green, and the remainder colour coded as black.

The Prioritisation Matrix is explained in more detail in Appendix 2.

4.4 Assigning Candidate Noise Management Areas

The colour coding of the SPS described in Section 4.3 above was the basis of determining Candidate Noise Management Areas ( CNMAs). Those areas with a red banding (the highest 1% of SPS scores) have been allocated CNMA status. The prioritisation process is described in further detail in Appendix 2 and the areas with CNMA status are described and mapped in Appendix 3.

An initial analysis of the total number of Candidate Noise Management Areas, using the bandings within Table 2, indicates 14,542 people in total are affected by road noise and 366 people in total are affected by railway noise in the CNMAs.

4.5 Assigning Noise Management Areas

The areas with CNMA status are shown in Appendix 3. During implementation of the Action Plan, a review process will be applied to each CNMA to determine whether it should become a Noise Management Area ( NMA). This process is necessary to verify the findings of the noise model from the prioritisation process in terms of the CNMAs. It will involve checking (and updating where necessary) of the data used in the Prioritisation Matrix and comparison of noise model assumptions regarding physical features with actual conditions on the ground (for example, presence of roadside noise barriers). The stages of the proposed review process are as follows:

Table 5 CNMA to NMA Checking Process

The assigning of Noise Management Areas and subsequent appraisal, planning, and implementation of mitigation measures in the NMAs form the core part of the Action Planning Process. The process of identification and prioritisation of actions to tackle noise in the NMAs is described further in Section 4.6 below.

4.6 Core Elements

In 1996, the European Commission Green Paper on Noise (1996) noted the financial impact of noise on society, with respect to the European Union, has been estimated to range between 0.2% to 2% of GDP. In addition, the Paper noted noise contributes greatly to reducing city dwellers' quality of life and may lead to health problems. There is a clear benefit to society to reducing environmental noise. At the same time however, reducing noise levels in identified NMA locations will often involve interventions requiring potentially significant expenditure and cost.

As part of assessing and identifying potential noise reduction measures in NMAs, it will be necessary to develop criteria to determine whether practical and cost effective noise mitigation measures can be implemented. In this way the available resources can be allocated to permit such measures to be implemented where benefit is justified and where the noise reduction potential is greatest.

Criteria for consideration in developing the prioritisation of actions in NMAs may include the following.

• Identifying the noisiest locations that affect the most people.
• Identifying the location of nearby sensitive buildings.
• Achieving effective noise reduction for the affected population.
• Minimising whole life cost.
• Reviewing existing maintenance and improvement programmes to identify when and how interventions can be implemented.
• Minimising disruption.
• Identifying appropriate and balanced Value for Money criteria.

It is envisaged the prioritisation process will be developed further by the Transportation Working Group and their partners to determine the NMAs following finalisation of the action plans (by early 2009). Thereafter a timetable and programme for a series of interventions, within the limits of available resources and alignment with planned maintenance, would be developed through the period of the first round Action Plan process (to 2012). The later stages of this planning period will also involve preparation for the second round of noise action planning required by the Environmental Noise Directive.

These core processes will be supported, as appropriate by other activities including participation in, and drawing on, relevant research and development in noise assessment and management. A description of the generic nature such supporting measures may involve is provided in Appendix 4.