South Western Railway (SWR) December 2018 Timetable Review

The South Western Railway (SWR) mainline to Weymouth connects London Waterloo station to the south-west of England. SWR provides suburban services in the counties of Surrey, Hampshire and Dorset, as well as regional services in Devon, Somerset, Berkshire and Wiltshire. The eight tracks entering London Waterloo are subdivided into two double track main lines (fast and slow lines) with the remaining four single-track lines serving suburban services (Windsor lines). During peak hours up to 24 trains per hour travel on the fast line in each direction. Despite the high density of block sections, the high number of trains per hour increases the probability of delays that can quickly propagate in the wider network.

In this project trenolab analysed current operations, evaluated the proposed 2018 timetable and developed improvement recommendations. As part of the project we identified critical trains and delay propagation scenarios, but also created and calibrated a microscopic simulation model of the critical Surbiton-Waterloo section. We used the calibrated model to test the draft December 2018 timetable paying specific attention to the additional platforms provided at Waterloo Station (the former international services platforms).

A sensitivity analysis performed in this study demonstrated that, even with almost perfectly on-time departures, delays would propagate due to the high number of trains planned during peak hours. The positive results of this study paved the way towards new projects between Network Rail and trenolab to test the May 19 and December 19 timetable drafts, as well as the simulation of other infrastructure projects and operational scenarios.