The first chart shows the reliability of services on the Severn Beach Line over the last six months. Of the services that ran, it shows which arrived early, on time, 1-4 minutes late and over 4 minutes late.
Credit: Andy Mac

The below charts show how the reliability of services on the Severn Beach Line has changed since May 2017. This includes cancellations, but groups the short-delay trains (1-4 minutes) with on-time trains.
Note to regular visitors, we have inverted the date order so that most recent months are at the top.



Noteworthy causes of service disruption/improvement since January 2020: |
January 2021 – announcement of lockdown #3 from January 5th onwards, GWR says it will continue to run the December temporary timetable |
December 2020 – new timetable with later services on Sunday mornings for Temple Meads engineering, also GWR staff shortages due to Covid-19 result in temporary timetable over Xmas and new year |
November 2020 – announcement of lockdown #2 from November 5th-December 2nd |
July 2020 – full timetable resumed from Saturday 11th July with 46pd on Saturdays – passenger numbers rising |
May 2020 – service increased from Sunday 17th May – 26pd Sunday, 32pd Saturdays, 50pd weekdays, still very low passenger numbers due to Covid-19 |
April 2020 – official Covid-19 timetable introduced Monday 30th March – service reduced to 26pd Sunday, 32pd Saturdays, 26pd weekdays (28pd weekdays from 13th April) |
March 2020 – at least 118 of these 134 cancellations were “planned cancellations” for GWR interim emergency Covid-19 timetable from 23-27th March (start date of lockdown #1) |



Noteworthy causes of service disruption/improvement for May 2017 to December 2019: |
December 2019 – increase in IET London service frequency |
December 2018 – services are routed via four-tracks on Filton Bank |
Autumn 2018 – Filton Bank blockade 27th October to 18th November plus weekends of 13th/14th Oct, 24th/25th Nov, 1st/2nd Dec |
Summer 2018 – several weekends of engineering bustitution |
July 2018 – Network Rail complete BASRE/ARS tweaks to improve SBL regulation |
Spring/Summer 2018 – GWR introduce measures to improve Turbo 166 performance on SBL, e.g. intermediate door controls |
April 2018 – Network Rail (NR) complete Bristol Area Signal Renewal & Enhancement with some disruption to SBL services |
March 2018 – SBL problems due to snow |
July 2017 – issues with introduction of Turbo 166s |
Footnotes: |
“Late” = services 5 or more minutes late on arrival at Severn Beach Line destination northbound, or Bristol Temple Meads southbound |
“Cancellations & turnbacks” = includes services cancelled throughout, services turned back prior to (or started after) scheduled stations and services that skipped scheduled stops |
“On Time” = services run to time or less than 5 minutes late |
This data has been collected variously from realtimetrains, raildar and recenttraintimes, none of which guarantee 100% accuracy. (AM/TM/CJD) |
Number of services run per month depends on month length, weekdays in a month, extra summer Sunday services and scheduled timetable changes for engineering |