Tube Noise written answers September 2020
Question No: 2020/3115
Andrew Dismore
TfL have informed me that they will not be proceeding with the installation of Delkor track fastenings, having trialled its use recently. Will you publish the report and results of the trial?
Answer for Tube Noise [1]
The Mayor
Last updated: 22 September, 2020
Officers are drafting a response
Tube Noise [1]
The Mayor
Last updated: 27 September, 2020
Transport for London (TfL) is still proceeding with the use of Delkor track fastening products where viable. TfL continues to investigate the feasibility of Delkor and other similar products in various locations across the Tube network, in order to identify the best practicable solution within its engineering and financial constraints.
In some locations, a particular Delkor product has been found unsuitable for engineering reasons. Where sleepers are spaced around one metre apart, on the Victoria line for example, adding this variant of Delkor baseplate would lead to flex in the rail, which causes corrugation. Given this, Delkor would not deal with the corrugation, which is the root cause of the residential Tube noise in this area. It could also lead to increased in-carriage noise.
The trial between Baker Street and St John’s Wood is still ongoing and installation is underway, expected to be completed in spring 2021. TfL needs to collect data for six months after installation has been completed in order to assess the longer-term effects of the product. I have asked TfL to keep you updated on the trial’s progress, and to share preliminary results as soon as feasible.
Question No: 2020/3116
Andrew Dismore
Did the Delkor track fastenings installation reduce tube noise? Did it have other impacts elsewhere, such as increased in-carriage noise?
Answer for Tube Noise [2]
The Mayor
Last updated: 22 September, 2020
Officers are drafting a response
Tube Noise [2]
The Mayor
Last updated: 25 September, 2020
Please see my response to Mayor’s Question 2020/3115.
Question No: 2020/3117
Andrew Dismore
Given the decision not to proceed with Delkor track fastenings, what further action are you taking to reduce tube noise?
Answer for Tube Noise [3]
The Mayor
Last updated: 22 September, 2020
Officers are drafting a response
Tube Noise [3]
The Mayor
Last updated: 27 September, 2020
Transport for London (TfL) and I take the issue of Tube noise very seriously. TfL continues to invest significant resource to investigate and mitigate the impact across the network over the last four years.
TfL’s targeted methods to try and reduce noise levels include its ongoing rail grinding programme, the application of additional lubrication, the installation of new rail and removal of redundant rail joints, where feasible and appropriate.
TfL is also working with suppliers to innovate and develop new technology to reduce noise levels across the network. Please see my response to Mayor’s Question 2020/3115 on Delkor track fastening products.
Question No: 2020/3118
Andrew Dismore
All known locations of severe tube noise in my constituency, Finchley Central, Golders Green, Kentish Town, Mornington Crescent and Warren Street have reported an increase in tube noise over the last few months. What is the reason for this in each location?
Answer for Tube Noise [4]
The Mayor
Last updated: 22 September, 2020
Officers are drafting a response
Tube Noise [4]
The Mayor
Last updated: 27 September, 2020
Transport for London (TfL) carried out rail grinding at Finchley Central in June 2020. As this is a tight curve, train wheels are slowly wearing the rail back into a comfortable equilibrium, which is causing the noise. This is normal and is expected to reduce in time through the passage of trains. TfL is monitoring the bedding-in progress.
TfL is aware of existing concerns at Golders Green and Kentish Town, and is managing these through rail grinding.
At Mornington Crescent, noise measurements were taken recently, and TfL is currently reviewing the results to identify the most appropriate solution. I have asked TfL to update you once this has been completed.
At Warren Street, TfL has undertaken a number of interventions, including the installation of track fasteners and flat-bottom rail conversion works, which have successfully reduced noise levels. When rail grinding is next carried out on the Victoria line, TfL will assess the levels of corrugation in this area, to determine whether it would benefit from rail grinding.
TfL continues to regularly monitor all known hotspot locations, to respond with the most appropriate and practicable mitigations.
Question No: 2020/3119
Andrew Dismore
I note a recent report by Hird Rail states that they are working with TfL on the potential for new sleepers which reduce tube noise: https://www.railbusinessdaily.com/hird-rail-introduce-new-unique-sleeper-to-reduce-noise-and-vibration-to-the-london-underground/
Has TfL tested their Hybrid Polymer Sleepers? What was the outcome of these tests, and will you consider a trial? If successful, will you install these in locations that suffer from tube noise?
Answer for Tube Noise [5]
The Mayor
Last updated: 22 September, 2020
Officers are drafting a response
Tube Noise [5]
The Mayor
Last updated: 27 September, 2020
While noise reduction is an added benefit, Transport for London (TfL) primarily uses Hybrid Polymer Sleepers in the open sections of the Tube network when carrying out ballasted track renewals.
Hybrid Polymer Sleepers cannot be used in the deep Tube (where the majority of Tube noise complaints relate to), primarily for reasons of fire compliance.
Question No: 2020/2561
Andrew Dismore
Do you have comparative costs, timelines and a prioritisation of locations for the installation of Hybrid Polymer Sleepers?
Answer for Tube Noise [2]
Unknown
Last updated: 21 September, 2020
Officers are drafting a response
Answer for Tube Noise [2]
Unknown
Last updated: 15 September, 2020
Officers are drafting a response
Tube Noise [2]
The Mayor
Last updated: 27 September, 2020
While noise reduction is an added benefit, Transport for London (TfL) primarily uses Hybrid Polymer Sleepers in the open sections of the Tube network when carrying out ballasted track renewals.
Hybrid Polymer Sleepers cannot be used in the deep Tube (where the majority of Tube noise complaints relate to), primarily for reasons of fire compliance.
Please see below the cost comparison of the softwood, hardwood and composite (Hybrid Polymer) sleepers:
- 6m Soft Wood Sleeper – £38.54
- 6m Hard Wood Sleeper – £86.20
- 6m Composite (Hybrid Polymer) Sleeper – £127.31
Hybrid Polymer Sleepers are a cost effective solution when balanced against the shorter lifespan of other varieties
