Capacity issues will worsen at South London junctions

The article in RAIL 843 on performance or capacity discussed (among other things) timetable planning problems around busy junctions.

It prompted me to write questioning the feasibility of eventually running 24 peak trains per hour through Blackfriars, using Thameslink. I have serious concerns about the station’s ability to cope, with so many Thameslink trains conflicting with so many other trains at the numerous South London junctions - particularly those along the main artery between Blackfriars and East Croydon.

My own experience of using Thameslink in 2017, almost all off-peak, is that I never had a journey uninterrupted by signal stops at one or more of Herne Hill, Tulse Hill or Streatham Junctions, or those in the Selhurst area.

This was at a time of a maximum of ‘only’ 15 or so peak trains leaving Blackfriars per hour, two-thirds of which do not use the full artery to East Croydon as they divert to the likes of Bromley and Sevenoaks, avoiding most of the junctions listed, or to Sutton leaving at Streatham Junction.

The Thameslink timetable judiciously allows between 27 and 31 minutes for the ten-mile crawl to East Croydon (best average speed of 22mph!), so despite often multiple hold-ups I have mostly arrived at East Croydon on time, no doubt as a result of ample recovery time being built in.

But when the number of trains increases following the introduction of Peterborough/ Cambridge to Brighton/ Sutton and other destinations, so (inevitably) will the number of conflicts at the junctions mentioned.

These pressure points seem at full capacity already, especially at the peak. It would be interesting to hear what the planners have in mind to cope with this obvious future capacity risk - maybe 40 minutes will be needed to get to East Croydon!

Do other readers share my experience of stop-start progress on this line, and do they share my concerns?

Dave Fletcher, Bradford