The Mayor's Ambient Noise Strategy - Greater London Authority

The Mayor’s Ambient Noise Strategy Mayor of London 53
4 policies and proposals
4.1 Chapters 4A to 4E below consider noise measures in relation to the main
‘ambient’ sources highlighted in the Greater London Authority Act 1999 -
road traffic, railways, aircraft, water transport, and industry. Chapter 4F on
spatial planning and urban design focuses on how London’s needs for
more development can be met sustainably. Chapter 5 on integrated noise
management includes other key noise issues not covered by the GLA Act
definition of ‘ambient noise’ but which need to be considered in a
coherent approach.
4.2 This structure serves to identify responsibilities and actions. However,
action on noise needs to take full account of situations where
people may be exposed to noise from more than one source. This
includes noise from different transport modes and inter-relationships
between ambient and non-ambient noise. In practice, the noise reduction
achieved by a measure can depend on what other noise sources are
present. For example, reducing traffic noise in one location could allow an
annoying hum from a ventilation unit, previously at least partially masked,
to be heard. In another location, the same reduction could result in
pleasant quiet. Effectiveness also depends on the sequence in which
measures are introduced. These are important issues for future action
plans, especially where different agencies are responsible for different
sources. This derives from the non-linear nature of noise and how
different sources combine (see Appendix A2). This distinguishes noise
from many other pollutants. It will make assessing and prioritising
packages of measures more complex. Further research is needed on this
as national and European noise policy develops.
4.3 Resolving tensions between the many different needs and aspirations of
people across the city will require a range of responses which will vary by
time and place. London contains areas of widely differing built form and
land use mix. Noise levels can vary significantly over small distances, as
well as across the city. Noise levels also vary greatly over the day,
evening and night, with different components on different days of the
week, especially at weekends. Night-time noise needs to become a focus
for ambient noise policy, including improving information and
understanding of effects.