Thameslink core broken - 13th July 26 - what could be done to improve things?

[ModernRailways]

Just tried to get into City Thameslink but it’s closed, staff at the gates said a tunnel has collapsed?

 

[rmHawk765]

staff at the gates said a tunnel has collapsed?

Oh dear. I think it's more likely to be an OHLE collapse or something that has been misinterpreted.

 

[pokemonsuper9]

Train operators have received reports of masonry and earthworks falling onto a train through a tunnel located between City Thameslink & Farringdon.

Staff are currently on site investigating the issue. Thameslink hope to have an update soon as to when the line could be reopened.

Incident: Farringdon | National Rail

Lines reopened between London Blackfriars and London St Pancras International. Find details of all current incidents on National Rail Enquiries.

www.nationalrail.co.uk

 

[zwk500]

Trains appear to be passing through both ways from the live berth maps.

 

[rmHawk765]

Was a rather quick fix.

All lines have reopened following urgent repairs to the railway between London Blackfriars and London St Pancras International. Trains running between these stations may still be cancelled, delayed by up to 45 minutes or revised.

Disruption is expected until 18:00.

Incident: Farringdon | National Rail

Lines reopened between London Blackfriars and London St Pancras International. Find details of all current incidents on National Rail Enquiries.

www.nationalrail.co.uk

Brighton to Cambridge is suspended according to NR, heavily disrupted service on everything else looking at RTT. Again, a failure of the TL network in terms of not being able to avoid the core.

 

[GraphitProjekt]

== Doublepost prevention - post automatically merged: 13 Jul 2026 ==

What kind of maintenance team/discipline would be dispatched to this kind of incident? Presumably a civil engineering department, but do they have local area teams stationed at Maintenance Delivery Units like Pway and S&T do?

 

[DelW]

Brighton to Cambridge is suspended according to NR, heavily disrupted service on everything else looking at RTT. Again, a failure of the TL network in terms of not being able to avoid the core.

Since only one Snow Hill tunnel was ever built, it's been a limitation for a hundred and sixty years. Building another north-south tunnel as a back-up / diversionary route would be an expensive exercise.

 

[The exile]

Since only one Snow Hill tunnel was ever built, it's been a limitation for a hundred and sixty years. Building another north-south tunnel as a back-up / diversionary route would be an expensive exercise.

In passenger terms it wasn’t a liability for 70 years from 1916!

 

[Bald Rick]

== Doublepost prevention - post automatically merged: 13 Jul 2026 ==

What kind of maintenance team/discipline would be dispatched to this kind of incident? Presumably a civil engineering department, but do they have local area teams stationed at Maintenance Delivery Units like Pway and S&T do?

First response would usually be a mobile operations manager, who will usually hold a ‘bridge bash’ competency, which would enable them to determine if there was something that would potentislly compromise safety. That is normally enough to,reopen the line, but if there is any doubt there is a call off contract for a rapid reposnse structural inspection by a civil engineer.

In this case the MOM evidently assessed the line to be safe.

I wonder if the building site immediately above the tunnel has anything to do with it.

The main disrpution on Thameslink today has actually been a points failure at Balcombe, and a bridge bash at the old favourite bridge in Leagrave.

 

[MadMac]

Didn’t something like this happen in the relatively recent past which turned out to be construction work above drilling into the tunnel?

 

[bramling]

Was a rather quick fix.

Incident: Farringdon | National Rail

Lines reopened between London Blackfriars and London St Pancras International. Find details of all current incidents on National Rail Enquiries.

www.nationalrail.co.uk

Brighton to Cambridge is suspended according to NR, heavily disrupted service on everything else looking at RTT. Again, a failure of the TL network in terms of not being able to avoid the core.

The way things have been recently, TL would be better to advertise when Brighton-Cambridge *is* running, given how much of a rarity that now is.

Thanks politicians for giving us this shambolic mess of a service.

 

[Recessio]

Didn’t something like this happen in the relatively recent past which turned out to be construction work above drilling into the tunnel?

Are you thinking of the Northern City line back in 2013? Drilling from a construction site above punched through into the tunnel - turns out NR were never consulted in the planning stage.

Report 03/2014: Penetration of a tunnel at Old Street

Penetration and obstruction of a tunnel between Old Street and Essex Road stations, London, 8 March 2013.

www.gov.uk

During the morning of 8 March 2013, a train driver reported that flood water was flowing from the roof of a railway tunnel north of Old Street station near central London. The driver of an out-of-service passenger train was asked to examine the tunnel at low speed and check for damage. The driver stopped short of the water flow and reported that two large drills (augers) had come through the tunnel wall and were fouling the line ahead of his train.

The augers were being used for boring piles from a construction site about 13 metres above the top of the tunnel. The operators of the piling rig involved were unaware that they were working above an operational railway tunnel. Its position was not shown on the site plan, or on any map available to either the developer or the local planning authority. As a consequence, Network Rail was not consulted during the planning application stage and was unaware of the construction activity.

The RAIB has determined that approximately half of the piles required for the new development would have intersected with the tunnel had they had been constructed. It has identified two learning points from this incident which are relevant to the construction industry: clients and design teams should be aware of the importance of information shown on land ownership records; and those carrying out investigations for proposed developments should be aware that not all railway tunnels are shown on Ordnance Survey mapping.

There was also a nasty one in Wanstead in 1986 from M11 construction. The train was severely damaged and I believe the driver was signed off for months.

 

[Spartacus]

Didn’t something like this happen in the relatively recent past which turned out to be construction work above drilling into the tunnel?

Not a million miles off. This time it appears that those pouring concrete weren't exactly careful about where they were pouring it. Luckily not much made it into the tunnels/onto the 700.....

In some ways down there it's less of a tunnel, more a mix of consecutive bridges and tunnels. Is it the Amazon building? Other 'careful' delivery

 

[jon0844]

Not a million miles off. This time it appears that those pouring concrete weren't exactly careful about where they were pouring it. Luckily not much made it into the tunnels/onto the 700.....

In some ways down there it's less of a tunnel, more a mix of consecutive bridges and tunnels. Is it the Amazon building? Other 'careful' delivery

Well, it if was Evri the concrete would have been poured a mile up the road and signed off as 'handed to resident'.

There must have been further fun in the morning when a bus hit a bridge at Finsbury Park. I thought buses could go under them, but seems not (although to be fair, I think the bus go under one bridge but not the next).

 

[Watershed]

There must have been further fun in the morning when a bus hit a bridge at Finsbury Park. I thought buses could go under them, but seems not (although to be fair, I think the bus go under one bridge but not the next).

It was a W3 bus, these terminate at the northwest side of the station but perhaps the driver took a wrong turn! Double deckers fit under the bridge on the south side of the station, but not under the bridge on the north side.

 

[jon0844]

It was a W3 bus, these terminate at the northwest side of the station but perhaps the driver took a wrong turn! Double deckers fit under the bridge on the south side of the station, but not under the bridge on the north side.

I wonder what else will happen this week. Users of the ECML (or up to Kings Lynn) are having a really bad month.

 

[norbitonflyer]

There was also a nasty one in Wanstead in 1986 from M11 construction. The train was severely damaged and I believe the driver was signed off for months.

Indeed - the auger went straight through the cab window - fortunately on the opposite side to the driver's position

 

[GordonT]

The way things have been recently, TL would be better to advertise when Brighton-Cambridge *is* running, given how much of a rarity that now is.

Thanks politicians for giving us this shambolic mess of a service.

There seems to be an impressive smorgasbord of flaws which compound disruption e.g. inflexible end-to-end driver diagrams, lack of "wiggle room" either side of the core to restore services and keep whatever happens to be "the good half" of services north or south of the core operating more reasonably.

 

[Spartacus]

There seems to be an impressive smorgasbord of flaws which compound disruption e.g. inflexible end-to-end driver diagrams, lack of "wiggle room" either side of the core to restore services and keep whatever happens to be "the good half" of services north or south of the core operating more reasonably.

I seem to find where exactly the issue occurs has a big impact on what type of service recovery there is, if any. Sometimes I feel issues affecting the MML are just left to work themselves out until services are approaching a hour late!

 

[riceuten]

I seem to find where exactly the issue occurs has a big impact on what type of service recovery there is, if any. Sometimes I feel issues affecting the MML are just left to work themselves out until services are approaching a hour late!

If there is a "service recovery plan", there seems little evidence of it on the ground. TSGN seem to instantaneously cancel the Brighton to Cambridge trains when there are any issues at all.

 

[GordonT]

TSGN seem to instantaneously cancel the Brighton to Cambridge trains when there are any issues at all.

The theory is that there are alternative services covering most of the route. However recently the alternatives have sometimes been more notional than actual at times where they have had their own separate disruption.

 

[bramling]

The theory is that there are alternative services covering most of the route. However recently the alternatives have sometimes been more notional than actual at times where they have had their own separate disruption.

The problem is that the stopping service isn’t a like-for-like alternative. If we take Letchworth to London, using the stopping service means in practice to arrive in London at the same time requires commencing the journey about 25 minutes earlier. As an example, in real-life terms for me that would mean the difference between whether or not I can go to the gym in the morning.

Also, when Cambridge-Brighton doesn’t run it means the stopping services become more crowded, with implications for people further in.

The Cambridge semi-fast service is important, and its unreliability makes it unfit for purpose.

There’s now four separate issues on GN:
* Fen Line unreliability - just looking at RTT for today there is loads of late running
* Persistent cancellation of Cambridge-Brighton service so users simply can’t depend on it
* Unteliability of Horsham-Peterborough, and implications for users between Hitchin and Peterborough who have no alternatives
* Complete meltdown and shutting up shop of the entire GN outer-suburban service during disruption

Pretty impressive for a route that is allegedly so “simple”…

 

[Jimcam]

The problem is that the stopping service isn’t a like-for-like alternative. If we take Letchworth to London, using the stopping service means in practice to arrive in London at the same time requires commencing the journey about 25 minutes earlier. As an example, in real-life terms for me that would mean the difference between whether or not I can go to the gym in the morning.

Also, when Cambridge-Brighton doesn’t run it means the stopping services become more crowded, with implications for people further in.

The Cambridge semi-fast service is important, and its unreliability makes it unfit for purpose.

There’s now four separate issues on GN:
* Fen Line unreliability - just looking at RTT for today there is loads of late running
* Persistent cancellation of Cambridge-Brighton service so users simply can’t depend on it
* Unteliability of Horsham-Peterborough, and implications for users between Hitchin and Peterborough who have no alternatives
* Complete meltdown and shutting up shop of the entire GN outer-suburban service during disruption

Pretty impressive for a route that is allegedly so “simple”…

Has there ever been a day - just one - since the inception of the Cambridge-Brighton service (2018?) when all the trains on that route have run, and have run the full length of their timetabled journey?

 

[GraphitProjekt]

Has there ever been a day - just one - since the inception of the Cambridge-Brighton service (2018?) when all the trains on that route have run, and have run the full length of their timetabled journey?

Although this question was asked somewhat rhetorically, or in jest. I did decide to have a look at the last 2 weeks of RTT data, and the answer is no. The best day I found was the 02 July where every train did run (with no more than 10mins lateness) but there were still two short forms: 9S05 ending at Gatwick and 9S14 starting from Three Bridges.

 

[Jimcam]

Although this question was asked somewhat rhetorically, or in jest. I did decide to have a look at the last 2 weeks of RTT data, and the answer is no. The best day I found was the 02 July where every train did run (with no more than 10mins lateness) but there were still two short forms: 9S05 ending at Gatwick and 9S14 starting from Three Bridges.

Not rhetorical nor, unfortunately, in jest. Whenever I've looked, there's always been at least one cancellation or short termination. I really don't think there has ever actually been a "clean" day.

 

[Transilien]

Not rhetorical nor, unfortunately, in jest. Whenever I've looked, there's always been at least one cancellation or short termination. I really don't think there has ever actually been a "clean" day.

I’m surprised that this wasn’t factored in before they decided to start this service.

 

[rmHawk765]

Thanks politicians for giving us this shambolic mess of a service.

If the issue was at Farringdon was it not possible just turn around as many trains as possible at St Pancras, Kentish Town, Blackfriars or City Thameslink & London Bridge? Instead of cancelling half the lot and letting everything else run an hour late...

It's really a fundamental flaw with just sending trains from everywhere to everywhere and making them share track with hundreds of other services. It works a lot better on XR because you can just send (some) trains that originally would've gone to Abbey Wood to Shenfield or vice versa, and terminate westbound trains short at Paddington, because it has full use of almost all of its infrastructure. Whereas a Brighton-Bedford train cannot just terminate at Kentish Town or Finsbury Park.

If there is a "service recovery plan", there seems little evidence of it on the ground. TSGN seem to instantaneously cancel the Brighton to Cambridge trains when there are any issues at all.

The Thameslink network is inherently so interdependent on everything that it is nigh on impossible to have a reliable recovery plan.

There’s now four separate issues on GN:
* Fen Line unreliability - just looking at RTT for today there is loads of late running
* Persistent cancellation of Cambridge-Brighton service so users simply can’t depend on it
* Unteliability of Horsham-Peterborough, and implications for users between Hitchin and Peterborough who have no alternatives
* Complete meltdown and shutting up shop of the entire GN outer-suburban service during disruption

Can also add crowding and subpar frequencies on the Inners to this list. The whole lot is broken... And the Horsham situation is a complete joke, I have a friend who lives on that section and has had to deal with it for years.

I’m surprised that this wasn’t factored in before they decided to start this service.

There are several pinch points on the route.

• The Cambridge line timetable is rather busy and there is no overtaking capability, despite the need for this having been identified years ago
• Welwyn Viaduct and needing to fit in with other possible delayed services on the fasts
• Finsbury Park - delay to literally any train can easily force a train to wait here due to the subpar layout
• A train cannot turn around at neither Finsbury Park nor King's Cross due to layout and capacity constraints respectively
• London Bridge has no southbound turnback facility (not even past the station)
• East Croydon and the Windmill Bridge Jn situation - trains often lose a few minutes here

== Doublepost prevention - post automatically merged: 14 Jul 2026 ==

The theory is that there are alternative services covering most of the route. However recently the alternatives have sometimes been more notional than actual at times where they have had their own separate disruption.

If a route's existence is only 'justified' by the presence of alternative services, the route is broken.

 

[Hadders]

No ticket acceptance was put in place yesterday with LNER between Stevenage and Kings Cross despite the severe disruption.

 

[Robski]

No ticket acceptance was put in place yesterday with LNER between Stevenage and Kings Cross despite the severe disruption.

The LNER "promise" of accepting GTR passengers has completely vanished. When GTR issued a "do not travel" notice because of major disruption a few months ago, I asked both GTR and LNER to accept tickets between Stevenage and London - only to be told they won't because a) the Cambridge stoppers were running (nothing else was!) and b) LNER is a separate company and has nothing to do with GTR passengers!

I can count on one hand the number of times LNER conveyed GTR pax between Stevenage and London. Most of those times it wasn't even advertised!!

 

[Transilien]

If a route's existence is only 'justified' by the presence of alternative services, the route is broken.

This reminds me of the RER D, which was too long and complicated to the point that many services were shortened and the 'interconnection' across Paris was stopped. If only the London Termini had the space to carry these services. Perhaps HS2 will allow a capacity release at Kings Cross, but I feel that that won't be enough and we will be stuck with this unacceptable situation.