Thursday, December 02, 2010

New Government Funded Study Shows Significant Effect of London City Airport on Noise Levels


A government funded, pioneering new way to measure environmental noise has shown the excessive noise levels that London City Airport brings to the Royal Docks.

The National Physical Laboratory (NPL), a world-leading centre of excellence in developing and applying the most accurate measurement standards, science and technology has just completed a case study on Greater London Authority owned land in Silvertown.

The case study, not solely focused on London City Airport but looking at all sources of noise in the area, involved using a new measurement based approach using multiple prototype noise sensors situated across the piece of land with a system called Dreamsys. The system has been proven to be accurate during the case studies and is expected to offer a more representative noise measuring method to work alongside predictive noise mapping currently used for environmental noise measuring. This system will also be financially more accessible and a unit is expected to cost no more than a high end mobile phone.

The data collected was used to create noise mapping and illuminating graphs indicating noise levels at particular locations on the site, and also consider different environmental noise factors. The noise data collected was then compared to the predictive noise maps (the technique already used, but felt widely to be insufficient in displaying the actual impact of noise on communities and fails to take into account accumulative noise effects). It was found that the new noise levels measured in the case study and compared to the predictive noise maps created by Hoare Lee were most similar at the nearest locations to the airport runway, however as you moved away the predictive noise maps became less accurate in representing the noise actually measured on the site. This can be seen here on the map points.

Of particular significance is the data collected during the volcanic ash flight ban last April. The MEMs DREAMSys units stationed on the Silvertown site measured a notable change in daily noise level - a 10dblaeq reduction. This translates as a 10db average reduction in noise levels.

NPL Dreamsys commented: "Lasting for just over 5 days for London airports, the grounding of flights was widely observed through the quieter skies and the absence of vapour trails, bringing discussion into the public domain on the usually unnoticed effects of air traffic".

This drop in noise level reflects measurement levels taken by FTF and local residents during the same period with the help of University College London's Mapping for Change enterprise and uploaded onto the Royal Docks Map. Richmond Council in West London also recorded a 10db drop in noise levels during the same period. Overall noise levels around London City Airport were also found to be comparable to levels under the flight path in Kew,West London based on a HACAN commissioned study carried out by Bureau Veritas.

The NPL Dreamsys data, is all available to view on user friendly maps which you can command to show you noise levels and the times of the noise here.

Dr Richard Barham, Principal Research Scientist in NPL's Acoustic Group commented:

"DREAMSys greatly expands the coverage offered by the measurement system in conventional equipment. It enables a large number of measurement points to be installed and used to continually monitor an area for months or even years. However, it is not intended that DREAMSys replaces prediction entirely. We hope that both approaches will complement each other, with the measurements being made in areas carefully selected on the basis that action plans would be significantly enhanced as a result. This shows the essential role that cutting edge measurement science can have in helping to meet specific challenges."

But overall the results of the NPL Dreamsys Silvertown case study offer many other illuminating facts from the real data collected:

1. London City Airport contributes excessive noise levels to East London and the peaks and troughs of each day perfectly reflect the times at which most residents express they are most disturbed by aircraft noise.

2. The issue of accumulative noise is raised - particularly road traffic and the DLR on the site. Not only did residents notice a huge decrease in aviation noise during the flight ban, but they also noticed a huge decrease in road traffic. London City Airport attracts huge amounts of road traffic with it's noise and air pollution, just under half of it's passengers arrive by private car or taxi. This makes a huge contribution to noise and pollution levels in Newham and the surrounding boroughs. FTF and HACAN have been actively lobbying for accumulative noise mapping.

Allowing airports to expand is not just about what happens within the terminal or on the runway - it has far reaching impacts across a very wide area. Accumulative noise impacts of aircraft with extra traffic, alongside pre-existing businesses should be always be part of any environmental consideration in planning. It suits aviation in general and London City Airport in particular to continue to ignore the impact of their business activities over the wider area, hence the keenness on the aviation industry on the current noise measurement methods they employ which fail miserably to represent what residents hear and what communities actually experience.

FTF welcomes the NPL's case study results at Silvertown and is excited at the prospect of Dreamsys being adopted more widely by local and central government but also the system being more affordable and accessible to many organisations and groups affected by excessive noise levels. Essentially, this system could offer government a better, more effective way to meet the EU noise directives, allow scrutiny and to promote better noise mitigation and management. It is a positive development and we hope it will be embraced. This should in turn influence planning decisions, and environmental and health impact studies as the effects of accumulative noise effects on communities has sadly been overlooked for too long. The cost of excessive noise levels on human health and develpment is something that needs to be looked at more closely, but an essential part of any such work needs to be supported by accurate and representative noise measurements to see localised cause and effect.  

More press coverage can be found here, here and here.