Request ID: FOI-2012-2122 Date published: 10 January 2022
You asked
The information required is a fully detailed history of the erection and maintenance of
this flyover and roundabout area. A head count of fatalities/injuries. A fully documented works schedule for the
imposition of the reduced speed limit effective at 00.01hours on September 10 2020.
All works effected from that time right up to the present, works in connection with signage, lighting
road surface and all and every change made along with times made and date(s) made.
In other words a fully documented history and an explanation of why the speed limit was
reduced and why on the material date.
It is vitally important that this information is received by return,
We answered
Our ref: FOI-2012-2122/GH
Thank you for your request received by Transport for London (TfL) on 9 December 2021 asking for information about Gallows Corner Flyer/Roundabout.
Your request has been considered under the requirements of the Freedom of Information Act 2000 and our information access policy. I can confirm that we do hold the information you require. You asked for:
The information required is a fully detailed history of the erection and maintenance of this flyover and roundabout area.
Gallows Corner Flyover is on the Major Road Network (MRN). It links the A12 Eastern Avenue with the A127 Southend Arterial Road, over the five-arm at-grade Gallows Corner roundabout.
The original flyover was built in 1970 as a temporary structure with a 20 year lifespan. Since then, structural and highway standards have advanced to improve road safety and maintainability. The Flyover consists of 13 simply supported composite modular steel and concrete slab spans of approximately 18m with a mass concrete ramp provided at each approach to allow traffic to transition onto the flyover deck. The spans are supported on steel trestles. The structure was designed by Braithwaite & Co with provision for simple erection and dismantling operations. Structures was fully refurbished between 2008 and 2009.
A head count of fatalities/injuries. For the 40 years to end August 2021, which is the latest processed information we have, there have been 721 personal injury collisions recorded at this site, three are recorded as fatal, 69 serious and 649 involved slight injury. Please find attached details of these collisions. One collision may involve multiple people being injured. Please note that all 2021 data is currently provisional and subject to change. Further details of personal injury collision information for the London area can be found on our website https://tfl.gov.uk/corporate/publications-and-reports/road-safety
For the purposes of answering your question, Gallows Corner is defined as the area within 200 metres of the centre of the junction (see the attached map.)
A fully documented works schedule for the imposition of the reduced speed limit effective at 00.01hours on September 10 2020. All works effected from that time right up to the present, works in connection with signage, lighting road surface and all and every change made along with times made and date(s) made.
Please find below, Gallows Corner Flyover maintenance works since September 2020;-
September 2020 - Implementation of 20mph & 7.5T Weight Restriction. Temporary and following permanent signage.
In other words a fully documented history and an explanation of why the speed limit was reduced and why on the material date.
A formal structural assessment of the flyover (Assessment Report dated March 2020 by TfL maintenance framework contractor Ringway) stated it was the assessor’s view at the time, based on engineering judgement, that Gallows Corner Flyover was unlikely to be identified as an immediate risk structure. However, it was expected that load mitigation measures will be required. It was anticipated that a BD79 risk review would recommend the installation of a 7.5tonne weight restriction. The weight limit would act to reduce the over-stress in the deck slab and increase any remaining residual fatigue life. The report recommended aformal BD79/13 risk assessment is carried out to inform the ongoing management of the structure. The report also recommended that abnormal loads are refused at this structure with immediate effect.
A risk assessment in accordance with BD79/13 The Management of Substandard Highway Structures was carried out in March 2020 also by Ringway (TfL’s maintenance framework contractor). Extracts from the report conclusions :
Based on the guidance in BD79/13 (and points raised in the report) it is considered that the structure does not pose an immediate risk to public safety when subject to normal highway loading. The exceptional loading risks arising from actions on the bridge would be mitigated to some extent by the reduction in the traffic speed and the imposition of a weight restriction.
If this is not the information you are looking for, or if you are unable to access it for some reason, please do not hesitate to contact me.
If you are not satisfied with this response please see the attached information sheet for details of your right to appeal.
Yours sincerely
Graham Hurt
FOI Case Officer FOI Case Management Team General Counsel Transport for London
