FOI request detail

Traffic light timings

Request ID: FOI-2307-2122
Date published: 28 January 2022

You asked

Please can you also let me know under an FOI how many traffic light timings and programmes were changed during the pandemic and where?

We answered

TfL Ref: FOI-2307-2122

I am writing further to my email below of 24th January 2022.

Since sending that response it has come to my attention that the data that was supplied to you with that response was incomplete. I apologise for this oversight. The revised spreadsheet now attached provides the full set of data we hold in relation to your request.

This spreadsheet now provides data based on the following work streams:
  1. Traffic light timings and programmes were changed during the pandemic (March 2020 when restrictions were first introduced to the date of the request - 6th January 2022) as part of our COVID response which reduced cycle times to better reflect a different pattern of demand on the network.  Please see the tab “Signal Timing Changes” in the attached spreadsheet which were specifically made by TfL Network Managers
  1. Traffic light timings and programmes were also changed during the pandemic as part of our annual Timing Review Programme - please see the tab “Timing Reviews” showing the locations of signal timing changes specifically made by TfL Network Managers
  1. The information originally provided, containing a list of 149 site references, shows the ‘PROM’ changes which were made (see the “PROM changes” tab).  PROM stands for Programmable Read Only Memory - each installation contains a unique software configuration program, which is used to customise the operation of the signal equipment for a particular junction or crossing.

Note further that some traffic light timings and programmes were changed as part of our “365/24/7” network management following response to incidents on the network and events, and other timings were changed where the intelligent transport systems have automatically responded based on set criteria, such as traffic. However, to gather this data for the period March 2020 - 6 January 2022 would exceed the costs limit for responding to FOI cases as set out under section 12 of the Freedom of Information Act. Under section 12, TfL is not obliged to provide data if it would cost more than £450 to determine if the information is held, and to then locate, retrieve or extract that data from  elsewhere. This is calculated at a cost of £25 per hour, equivalent to 18 hours work. Should you wish to receive this information, please can you narrow the period of your request or refer to a more specific location.

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,

David Wells
FOI Case Officer
FOI Case Management Team
General Counsel
Transport for London



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