TfL Ref: 2004-1920
 
Thank you for your request received by us on 2 October 2019 asking for information about the number of complaints received concerning noise levels on the London Underground from 2015 to 2019 and the highest decibel levels recorded during this period.
 
Your request has been considered in accordance with the requirements of the Environmental Information Regulations and our information access policy. I can confirm that we hold some of the information you require. You asked for:
 
1. The number of complaints received regarding noise levels on the London Underground broken down by year from 2015 to 2019. If possible, separate complaints between staff and others (i.e. members of the public)
 
The London Underground network supports around five million customer journeys per day and over 1.3bn journeys a year. We continuously take noise readings and review the track condition to assess what works can be done to reduce noise. There are various engineering initiatives which we are either trialling or aim to trial in an attempt to achieve this. For example, we are currently installing softer pads throughout our resilient track fastening sites to reduce airborne noise. Our loudest sites have already been completed and we are currently measuring the reduction in noise. Additionally, we are trialling other rail damping technology, which was installed on the Jubilee line earlier this year. We aim to have reduced the airborne noise in tunnels by the end of 2019.
 
Anyone affected by noise can contact our dedicated customer services line, which is available 24 hours a day, seven days a week via the link below:
https://tfl.gov.uk/help-and-contact/ 

The attached numbers of complaints received per London Underground line represents the data we have been able to retrieve from our reporting system since 2017; a change of database was implemented at this time and we no longer hold this information prior to 2017. The Hammersmith & City and Circle line services are grouped together for reporting purposes due to both lines sharing much of the same rail track infrastructure. Please note that the information displayed in the tables below includes all classifications of noise that we have categorised on our reporting system, from tannoy announcements to those that are track related for example.
 
2. The highest recorded decibel level on underground lines broken down by year from 2015 to 2019. If possible, break these figures down by the underground lines
 
Since this is not recorded in the format requested, we would need to identify, locate, extract and review a significant volume of noise recordings and documentation for the purposes of your request. We are therefore refusing Question Two in accordance with the Environmental Information Regulations under Regulation 12(4)(b), as we believe that this is ‘manifestly unreasonable’ because providing the information you have requested would impose unreasonable costs on us and require an unreasonable diversion of resources.
 
For example, the noise monitoring equipment we use for the London Underground network takes a noise reading several times a second. The noise surveys we undertake are carried out on an entire line three times over a period of two or three days. All of this data is then used to calculate the average noise between two London Underground stations. Some locations between stations may have a short period of louder noise recorded, which is noticeably higher than the average. To identify this short period of louder noise, the original data from the monitor would need to be reviewed. In some cases this original data is likely to no longer be available as the loudest noise was not a required measure to obtain at the time. It is also important to note that the maximum level would not be a true representation of noise level experienced throughout a specific London Underground line service.
 
Therefore, identifying and collating the information you have requested would present a significant burden to limited resources as it would require a manual review and comparison of a large volume of data.
 
The use of this exception is subject to a public interest test, which requires us to consider whether the public interest in applying the exception outweighs the public interest in disclosure. We recognise that the release of information would promote accountability and transparency in public services. However, the time it would take to provide the information you have requested would divert a disproportionate amount of our resources from its core functions and, taking into account the information already published on our website and in business plans (for most of the larger projects), on balance we consider that the public interest currently favours the use of the exception.
 
If this is not the information you are looking for, or if you are unable to access it for any reason, please do not hesitate to contact me.
 
Please see the attached information sheet for details of your right to appeal as well as information on copyright and what to do if you would like to re-use any of the information we have disclosed.
 
Yours sincerely
 
 
Jasmine Howard
FOI Case Officer
Information Governance
Transport For London

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