The Mayor's Ambient Noise Strategy - Greater London Authority

The Mayor’s Ambient Noise Strategy Mayor of London 41
Box 14: Transport Strategy assessment by MVA for TfL - summary
■ Modelling of basic noise levels, using methodology in ‘Calculation of
Road Traffic Noise’ (CRTN) Department of Transport, 1988, indicated
that many roads on the network, such as motorways and major roads,
particularly those carrying a significant amount of commuter traffic
such as the North Circular and the A40, and some central area roads
such as Oxford Street, had noise levels of over 76 dB for 2001.
■ The 2001 base case was projected to 2011 without measures in the
Mayor’s Transport Strategy. Traffic noise would increase on all the
modelled roads. The smallest increases would be concentrated in
central London, where a 15 per cent increase in bus flow would be
partially offset by a 1.6 per cent decrease in car flow. Oxford Street,
where traffic is predominantly buses, would have the largest increase in
noise levels in central London - but this assumes no reduction in the
noise of buses.
■ The 2001 base case was projected to 2011 with measures in the
Mayor’s Transport Strategy. Traffic noise would decrease on several
routes in central London. This would be as a result of Congestion
Charging and a consequential decrease in car flow in central London.
The highest projected increases in noise levels (up to 1.6 dB) would be
on roads with high bus flows, associated with an overall increase of 40
per cent in buses, on some links in central London, in town centres and
on other major bus routes. However, this calculation included buses in
the heavy vehicle category of ‘Calculation of Road Traffic Noise’. In
practice, improvements in technologies are likely to reduce bus noise
levels by 2011. Quiet fuel cell buses are being trialled in London.
Benefits from quieter buses would be greatest in central London,
where buses comprise a large proportion of all vehicles. Laying quiet
road surfaces was assessed to give noticeable improvements on busy
roads (those carrying over 25,000 vehicles per day).
■ Modelling of railway noise levels, using methodology in ‘Calculation of
Railway Noise’ (CRN) Department of Transport, 1995, showed the
busiest national rail routes into and out of London as the noisiest, while
those with higher speeds were also relatively noisy. Modelled change
between 2001 and 2011 without measures in the Mayor’s Transport
Strategy would, for the most part, be less than 2 dB, with the exception
of the Channel Tunnel Rail Link, which, however, would be in tunnel on
its approach to London to avoid noise and other impacts. Increased
services with the Mayor’s Transport Strategy lead to a projected increase
of over 2dB on a number of routes, particularly from the major stations
north of the Thames. Services on the West London Line, East London
Line, and the Gospel Oak-Barking Line also show increases, as does
Crossrail (although this is in tunnel through the central area). For the
network as a whole, however, the increase in noise levels is generally