Network Rail has outlined plans to work on the stretch of rail between Redhill and London between 2019 and 2024.
The rail operator said in a study that efforts to relieve Brighton Main Line congestion should be focused on the northern section of the route in Control Period 6.
“Already committed capacity interventions in CP4 and CP5 will have a significant impact in decongesting some peak trains, in particular those that serve London Bridge,” said the report.
“The key constraints to unlocking a further increment of capacity on the BML are the flat junctions and the number of fast line platforms at key stations. These constraints are not only limiting capacity on the route but are now a day-to-day part of the reliability challenge of delivering the existing timetable.
“The most heavily utilised flat junctions, platform faces and plain line sections are in the inner area of the route, ie from Stoats Nest Junction (north of Redhill) inwards to London, and it is here that the main focus of effort needs to be in CP6. These locations are acting as a bottleneck for the whole route.”
Campaign group BML2, which wants a new route between Brighton and Croydon, disputed the report’s findings.
“Indisputably, relief of the overburdened Brighton Main Line can only come with an effective ‘rail bypass’ – as achieved in 1900 at congested Redhill Junction.,” said BML2 in a statement.
“As politicians are beginning to concur, the south needs a new main line between the Sussex Coast and London.”
Network Rail is to carry out further work before publishing a draft Sussex Route Study later this year.