Action Plan Prioritisation Process

Background

The Environmental Noise (Scotland) Regulations 2006 require noise action plans to meet the following key objectives.

  • Prevent and reduce environmental noise where necessary, and in particular where exposure levels can induce harmful effects on human health.
  • Preserve environmental noise quality where it is good.
  • Manage noise issues and effects, including noise reduction if necessary.
  • Aim to protect Quiet Areas against an increase in noise.
  • Apply to the Most Important Areas as established by strategic noise maps.

Identification of Noise Management Areas (NMA)

The strategic noise mapping noted earlier in ,Strategic Noise Mapping and Action Planning and the related population exposure, provide the basis for identifying areas where the above objectives can be prioritised, and delivered, under the TNAP, and where noise management efforts can be focused, and effective. These areas are referred to as Noise Management Areas (NMAs), and Quiet Areas (QAs),

The identification of NMAs followed a three stage process as noted in the Table 12 below.

Table 12 - Stages of NMA identification

Number

Stage

Details

1

Identify Noise Areas

Define areas exposed to environmental noise which may be harmful to human health, as indicated by international guidance. Levels chosen for road and rail and number of people exposed are shown in Table 13 below.

2

Identify Noise Management Areas

These are a subset of Noise Areas, where the health effects are highest, determined through a consideration of noise exposure levels and the number of people exposed to noise. They have been defined using a heatmap density criterion of people highly annoyed to identify the top 3% of the area of Scotland.

3

Choose Noise Management Areas

This involves a selection of Noise Management Areas identified during the implementation of the TNAP.

Stage 1 involves an assessment of the strategic noise modelling to identify areas where people were experiencing noise above the WHO Environmental Noise Guidelines for the European Regions values, 54 dB Lden (rail) and 53 dB Lden (road). These are defined as Noise Areas.

Stage 2 involves an assessment of the areas identified in Stage 1 to determine locations where the health effects are highest, determined through a consideration of noise exposure levels and the number of people exposed to noise.

Stage 3 involves choosing a series of NMA to be managed during the period of the TNAP. These will be chosen by the TNAP delivery group based on cost benefit ratio and policy alignment.

The outcomes of the stage 2 process was determined using Geographical Information Systems (GIS) software, which created a heatmap, identifying areas with higher concentrations of people “highly annoyed,” as set out in the WHO guidelines, linked above. Information on the make up of the proposed Candidate Noise Management Areas (CNMA) is listed in Table 13 below.

Table 13 - Stage 2 Process Candidate Noise Management (CNMA) Outcomes

Source

Total CNMA

Total Population

Highly Annoyed (HA) Population

HA Threshold Used

(people per 100 m2)

Road

158

70,209

12,378

34

Rail

16

4,895

1,013

39

A validation and prioritisation process will be undertaken during the implementation of the TNAP to determine which CNMA areas should be considered first as Noise Management Areas.

Validation will include an assessment of each CNMA to determine any significant changes from the modelling data, and define these as NMA. The prioritisation process will evaluate each NMA and rank these in terms of deliverability.