So, my final word in this series, at least for now: My thoughts on what could have been done better, instead of suspending the network for so long.
Firstly, some opinion.
Sadly, I’m sceptical we’ll see any accountability or transparency from TfGM nor the Metrolink operator (KeolisAmey) about what could have been done better.
TfGM appears to be engaged in finger-pointing at their supplier:
“I’ve emphasised to the operator the absolute urgency in which they need to get services running” – Danny Vaughan, TfGM Head of Metrolink.
Meanwhile, the supplier, KeolisAmey Metrolink seem to be hiding behind a “cloak of safety”:
“We take customer safety seriously so the decision was taken to suspend all services.” – Aline Frantzen, Managing Director of KeolisAmey Metrolink.
This isn’t the first time that KeolisAmey senior staff have hidden themselves. Following the last network-wide failure in July they refused to speak to the local press, saying they were “busy dealing with the problem”: “Aline Frantzen, new Metrolink MD, and Alistair Gordon, chief executive of Keolis UK, were not available to speak to the M.E.N.”
These people are senior folks, and putting what I call “a face on a farce” is part of their job while their staff work behind the scenes to fix whatever’s broken. It’s not their job to hide.
Okay, that’s the opinion/minor rant over.
Now the fun bit. What could have been done better at 0830 last Friday morning…
Receive report from incident trams about what has happened. Assume the incident trams cannot be moved. It is also desirable to prevent other movements in the area to preserve evidence until the Incident Officer arrives. It’s fairly certain this is going to be a long one, and we still have people to get to work. We can’t just throw our hands in the air and cry “stop the job” for the whole network, even if we have no choice but to suspend service in the incident area.
The first 15 minutes:
A “line blocked” situation now exists between:
- Exchange Square and Deansgate/Castlefield on 2CC, both directions.
- Piccadilly Gardens junction and Deansgate/Castlefield on 1CC, both directions.
What’s left on the network that’s good?
- Bury to Piccadilly via Market St
- Rochdale to Victoria
- Victoria to Exchange Square
- Ashton to Piccadilly
- All the South Manchester network up to Deansgate/Castlefield
Assumptions:
- Drivers sign all routes so can operate trams to anywhere under direction of Control.
- We can handle most issues with relieving/re-crewing/crew out of place, either by delaying breaks within legal limits, using alternative relief points, mobilising rostered spare drivers, and amending driver duties as required – the published plan is out of the window whatever now, anyway.
- We don’t want to block running lines unnecessarily with reversing trams, as this causes knock-on delays – reverse in loops/sidings only where possible.
- We can’t run non-ATS trams to Bury and Altrincham.
The network is effectively split in two pieces by the incident.
It’s the morning peak and the dominant flows are people heading into Central Manchester. We need to get trams as close into Central Manchester as we can.
Let’s look at the Northern part of the network first. This is actually going to be the easier one to maintain service on.
- Bury – Piccadilly: This is completely unaffected by the incident and could keep going.
- Bury – Altrincham: Can’t get past Market St.
- Rochdale/Shaw – Didsbury: Can’t get past Exchange Square.
- Ashton – Eccles: Can’t get past Piccadilly Gardens
Here’s how, immediately following the incident, the service could have been reformed to keep things moving:
- Bury – Piccadilly: No change.
- Bury – Altrincham: Continue from Market St via Piccadilly to Etihad Campus (maintains 6 minute headway between Piccadilly & Etihad).
- Rochdale – Didsbury: Continue from Victoria via Piccadilly to Ashton, effectively taking over that end of the Eccles – Ashton service.
- Shaw – Didsbury: Terminate at Exchange Square and reverse on crossover on Corporation St, return to Shaw.
- Ashton – Eccles: Continue from Piccadilly Gardens via Market St to Victoria and thence to Rochdale.
We also need to get rid of any Piccadilly – MediaCity trams on this side of the blocked line as if we can’t usefully repurpose them to keep the other lines running, they are in the way. We can probably stable one in the Sheffield St turnback road, and send any more to Queens Road depot.
The above changes will keep the Northern half of the network moving. We’ve even a) theoretically preserved headway and capacity on the majority of those sections of route, and b) managed to do the right thing with the ATS fitted trams for the Bury line. The benefit of sending the Bury – Altrincham trams to Etihad also means when the line is clear and it’s time to re-form the service, we can send them forward from Etihad as Altrincham trams if we choose.
The Southern Network is more tricky as it’s more impacted by the incident. Except for the Airport – Deansgate tram, everything is going through the centre.
- Firstly, nothing else can proceed beyond Deansgate until the incident site is cleared for operation. This could take a while.
There’s two ways we can turn trams around at Deansgate in this situation, one is in the centre platform, like the Airport trams usually do. The other is on the reversing crossing around the corner, on the viaduct up the side of Manchester Central – a tram arrives on the City Centre-bound or middle platform, unloads, departs to the crossover, reverses, and comes back on the Southbound platform to pick up passengers.
This still does limit how many trams we want running to Deansgate though. We certainly can’t support the close headway that is planned to run.
We need to thin the service down, and quickly, before it bottlenecks.
First thing would be to suspend the MediaCity – Piccadilly service, and run all Eccles trams via MediaCity to maintain service there. There are two double unit sized platforms at MediaCity, so we could berth two units there, and still leave one platform vacant for use by the remaining services, even if they happened to be formed of double units. We can also recess a couple of trams in the centre siding at Cornbrook.
Anything that’s already between Cornbrook and Deansgate is a done deal. We’re turning it around at Deansgate, whatever it is. Turn it around and send it back to the outer end of it’s route. Abandon even headwaying at this point, we just need to clear what’s between Cornbrook and Deansgate and get it back heading out of town – remember, there’s people using the network to head out of town too.
With the MediaCity service taken out, we have the following happening:
- Didsbury line services approaching at 6 minute intervals
- Airport line services approaching every 12 minutes
- Altrincham line services approaching every 6 minutes
- Eccles line services coming every 12 minutes.
So, that’s still a tram every 2 minutes, technically. Can it be done?
We know that during the Summer of 2016, they turned all routes around here during the blockade to finish and connect the new St Peter’s Square stop, and these were:
- East Didsbury – Deansgate
- Altrincham – Deansgate
- Eccles – Deansgate
These all operated on 12 minute headways (the Airport line terminated at Cornbrook, as did half the Altrincham trams), which means a tram every 4 minutes, so half the trams we would be getting once we’d dropped out the MediaCity service.
I would suggest it cannot be done reliably and we need to reduce even further to prevent tailbacks on the viaduct at Castlefield.
If the Airport service is cut back to Cornbrook, which is a fairly normal technique used by control during congestion or problems between Cornbrook and the City Centre, that at least drops another movement out at Deansgate.
We’ve also got the Trafford Depot available if we have too many trams around and need to get some off the road, and this depot is readily accessible from all passing lines, without a need to perform any reversing or shunting – moves to and from the depot are straight-in/straight-out. We can also readily terminate or reverse trams approaching from Firswood or Old Trafford here if we need to relieve pressure in the Cornbrook area. It doesn’t help get people to work, but it helps prevent gridlocking if it seems like it’s a risk, and is an option.
Let’s assume we can take a tram every 3 minutes at Deansgate and turn it around using one or the other of the two techniques. That’s 4 trams every 12 minutes. We also want to try and make the best use of the double units we have, if we can. We can run the following service on the South side:
- Didsbury – Deansgate every 6 minutes, mostly single, with some double trams
- Altrincham – Deansgate, double trams, every 12 minutes
- Eccles – Deansgate, single trams, every 12 minutes
- Altrincham – Cornbrook, single trams, every 12 minutes
- Airport – Cornbrook, single trams, every 12 minutes
So, that’s the system kept mostly moving for the first 30-60 minutes following the incident.
Once rush-hour has cleared, so from 0930, the sensible move would be to drop to a 12 minute headway on the South side while the network operates in a degraded state:
- Didsbury – Deansgate every 12 minutes
- Altrincham – Deansgate every 12 minutes
- Eccles – Deansgate via MediaCity every 12 minutes
- Airport – Cornbrook every 12 minutes.
We know this service pattern can be supported, we can easily take trams out of traffic from all directions at Trafford Depot, and berth trams at Altrincham.
We can consider redeployment of the released tram drivers as necessary as well.
Once St Peter’s Square could be re-opened to traffic on all lines except the line blocked by the incident, we can reform to the following, each on 12 min headways:
- Bury – Altrincham via 2CC
- Didsbury – Shaw via 2CC
- Rochdale – Ashton via Market St
- Bury – Etihad Campus
- Altrincham – Deansgate
- Eccles – Deansgate via MediaCity
- Airport – Cornbrook
I accept this involves a reduction in headway on some South Side routes, but that’s because they are constrained, both in routes through the city centre, and where services can be turned around before the blockage.
The Northern part of the network and the Ashton line have maintained their advertised headways, the Ashton line maintains through services into Piccadilly Gardens rather than turfing everyone out at Piccadilly, and with a change at Victoria, passengers can access the South side of the network from there.
So that’s the network kept moving. People arriving at work maybe only 10/15 minutes late rather than 30-60 minutes late. People in Oldham not left wondering why they can’t get where they need to go because of an incident 10 miles away.
Why didn’t the above happen? I don’t know the answer.
The impression I get from an informed rider’s perspective of incident handling at Metrolink is that they cope reasonably well with routine issues affecting a single route, but if there is a major incident, their attention becomes turned wholly to the incident, rather than breaking the responsibilities of incident handling and service recovery up.
It feels like the disruption handling procedures and training may be out-dated, maybe written for a time when the network was much simpler and a 30-35tph service didn’t exist, or that there simply aren’t enough pre-rehearsed plans for service recovery, written up into “run-books”, that could be rapidly referred to and activated.
I’m honestly happy and willing to be corrected if these things do exist, but if they do, that then that raises the question of whether they are reviewed and audited regularly, and updated where necessary.
The message that was sent last week by suspending service for 30-60 minutes network wide is “We currently have no plan for this” regardless of whether that is really the case.
Media reports in the last week state that there will be a RAIB investigation into the collision between the two trams. I don’t believe that anything I’ve written here is in any way directly related to the collision, but more the operator’s response to reforming the service in response to the reactionary effects of the incident. I don’t believe any of the above is prejudicial to the RAIB investigation.
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