The first chart shows the reliability of services on the Severn Beach Line in 2020. 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 chart shows 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.

Severn Beach Line Reliability
Severn Beach Line Reliability
Noteworthy causes of service disruption/improvement are listed below:
July 2017 – issues with introduction of Turbo 166s
March 2018 – SBL problems due to snow
April 2018 – Network Rail (NR) complete Bristol Area Signal Renewal & Enhancement with some disruption to SBL services
Spring/Summer 2018 – GWR introduce measures to improve Turbo 166 performance on SBL, e.g. intermediate door controls
July 2018 – Network Rail complete BASRE/ARS tweaks to improve SBL regulation
Summer 2018 – several weekends of engineering bustitution
Autumn 2018 – Filton Bank blockade 27th October to 18th November plus weekends of 13th/14th Oct, 24th/25th Nov, 1st/2nd Dec
December 2018 – services are routed via four-tracks on Filton Bank
December 2019 – increase in IET London service frequency
March 2020 – at least 118 of these 134 cancellations were “planned cancellations”  for GWR interim emergency Covid-19 timetable during week 23-27th March
April 2020 – official Covid-19 timetable introduced Monday 30th March – service reduced to 26pd Sunday, 32pd Saturdays, 26pd weekdays (28pd weekdays from 13th April)
May 2020 – service increased from Sunday 17th May – 26pd Sunday, 32pd Saturdays, 50pd weekdays, still very low passenger numbers due to Covid-19
July 2020 – full timetable resumed from Saturday 11th July with 46pd on Saturdays – passenger numbers appear to be rising