Request ID: FOI-0842-2122 Date published: 15 September 2021
You asked
Dear Transport for London,
Dulwich Low Traffic Neighbourhood (LTN) instigated by Southwark Council. Boundary roads have experienced longer traffic queuing since this LTN has been implemented. What studies, reports, recorded extra time data or similar do you have re the time buses take going along these roads ie South Circular (A205) between Lordship Lane and Croxted Road junctions, Croxted Road between Thurlow Park Road and Norwood Road junctions, Norwood Road between Croxted Road and Half Moon Lane junctions, Half Moon Lane / East Dulwich Grove between Norwood Road and Lordship Lane junctions and Lordship Lane between East Dulwich Grove and the South Circular compared with before the LTN was introduced?
Thank you
We answered
TfL Ref: 0842-2122
Thank you for your request received by us on 21 July 2021 asking for data and reports about bus journey times in the Dulwich Low Traffic Neighbourhood (LTN) area.
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 information regarding the:
Dulwich Low Traffic Neighbourhood (LTN) instigated by Southwark Council. Boundary roads have experienced longer traffic queuing since this LTN has been implemented.
What studies, reports, recorded extra time data or similar do you have re the time buses take going along these roads ie South Circular (A205) between Lordship Lane and Croxted Road junctions, Croxted Road between Thurlow Park Road and Norwood Road junctions, Norwood Road between Croxted Road and Half Moon Lane junctions, Half Moon Lane / East Dulwich Grove between Norwood Road and Lordship Lane junctions and Lordship Lane between East Dulwich Grove and the South Circular compared with before the LTN was introduced?
Whilst the Low Traffic Neighbourhood was introduced in response to the Pandemic as a rapid delivery measure following a bid by the London Borough of Southwark, it is important to note that the journey time bus data we hold is not a comparison of like for like conditions, as there are generally fewer people using London Buses because of the pandemic.
Given that the LTN was introduced as a rapid delivery measure, no modelling or studies were undertaken by TfL. However, ‘Spreadsheet A’ attached consists of iBus data for the bus corridors we have been monitoring around the Dulwich LTN; generated from the automatic vehicle location and radio system, which provides real-time journey information. This is the most recent summarised data we hold, covering the period from 15 March 2019 to 30 July 2021 for the bus routes and highways listed below, as mentioned in the attached ‘methodology’ tab:
- A205 (P4, P13)
- Croxted Rd (3, 201)
- Dulwich Village (P4)
- East Dulwich Grove (37, 42)
- Grove Vale/Champion Park (P13, 40, 42, 176, 185, 484)
- Half Moon Lane (37)
- Lordship Lane (P13 (Northbound only), 40, 176, 185, 197)
- Norwood Rd (68, 196, 322, 468)
- Red Post Hill (P4, 42)
The following explanations for the acronyms referenced in the spreadsheet are listed here:
JT – Journey Time Avg - Average EB – Eastbound WB – Westbound SB – Southbound NB - Northbound
Additionally, ‘Spreadsheet B’ summarises the average weekday bus journey time data per hour for all bus corridors surrounding the Dulwich LTN, versus the corresponding 2019 period average. These journey times are stop-to-stop times only and so exclude dwell time.
The methodology used for this data is also contained in the spreadsheet, stating in part that threshold values were found by taking the mean +/- 1 standard deviation, for the weekly corridor averages during the baseline period covering 11 March 2019 to 9 March 2020. These thresholds are meant to represent ‘normal’; journey times. This allows for a reasonable amount of week-to-week variation but gives a threshold above which journey times would be deemed above ‘normal’.
A bus corridor is reported to revise and improve the bus operating capabilities for journey times on the roads when there are three or more consecutive weeks of above threshold bus delay. There is constant work to improve bus journey time outcomes. As of 23 August 2021, there were no corridors failing the criteria for revising and improving bus journey times.
Whilst the LTN is not a bus priority scheme as such, there are many considerations to bear in mind with the bus journey times provided. For example, varying levels of road traffic demand throughout the day, reduced use of public transport during the pandemic, together with social distancing measures in place.
Furthermore, a copy of the ‘Dulwich Streetspace Monitoring Report for Southwark Council’ is attached, which compliments the aforementioned research for this area.
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 FOI Case Management Team General Counsel Transport for London
