In the opening post in this series, I put forward a series of probably common questions as to why it took so long to recover service following the Metrolink disruption on 10th November:
- Why couldn’t the trams be diverted via 2CC?
- Why couldn’t the trams be turned around short of the destination?
- Why couldn’t the trams just run to a different destination?
- Why was the Bury-Piccadilly service, which doesn’t go anywhere near the incident, stopped?
Let’s take the first of these:
Why couldn’t some trams be diverted via 2CC (the Second City Crossing)?
Once it was ascertained that the incident was only affecting one line, the one which fed trams from St Peter’s Square toward Piccadilly Gardens, then you would think it becomes feasible to divert the approaching City-bound trams from Deansgate via 2CC, taking them “off-route”.
The problem arises with what you do with them once they reach the other side of the City Centre.
It is very difficult for a Piccadilly, Etihad or Ashton-bound tram to regain the booked line of route, as there is no easy way from the far end of 2CC to head back in to town via Market St. There is no direct link between 2CC and this line without reversing direction.
So, the route via 2CC becomes an easy option for the existing Altrincham-Bury services, but that’s largely it without a more complex operation.
It’s also likely that routing all the trams down the 2CC would cause road congestion as well, as Cross Street is a shared right of way between trams and road traffic. So it becomes necessary to “thin out” the service.
Once the trams get to Victoria you have to do something with them, either turning them short of destination, reversing them, or doing something else with them, such as taking them out of traffic and running them to depot.
This leads us nicely onto…
Limited Places to turnback or “recess” trams
While Metrolink has a number of emergency turnback crossings which can be used to maintain service during periods of disruption, these effectively block the line while the driver changes from one end of the tram to the other, then receives a slot to cross over to the other line and return in the opposite direction. A queue of trams could quickly build up if this happened along a busy section of line. Some of these are also “unsignalled moves” so are only useable under very specific circumstances.
Besides the outer ends of the network, there are some specific turnback locations which have extra platforms or sidings to cater for reversing trams:
- Timperley – has a siding so a Southbound tram can turn around and return toward the City Centre. This is most commonly used when trams can’t operate on the Network Rail managed section between Timperley and Altrincham, but is occasionally used to manage late running.
- Cornbrook – there is a long centre siding here, this was until recently the usual terminus for the Airport Line, it can hold a good number of trams, and is useful during emergencies, both for recessing trams and reversing trams approaching the City Centre.
- Deansgate – there is a centre platform which is bi-directionally signalled – that is trams can arrive and depart in either direction and reverse. It is currently regularly used for reversing the Airport service.
- Piccadilly (Sheffield Street) – outside the back wall of Piccadilly station undercroft this has a centre track for reversing trams that have arrived from the City Centre and sending them back into Piccadilly station and thence toward Piccadilly Gardens. This is normally used for reversing two services, MediaCity-Piccadilly and Bury-Piccadilly. There are a further pair of crossovers in the “tunnel” underneath Piccadilly Station, these are most commonly used for reversing a tram from the Ashton direction and sending it back that way.
- Etihad Campus – there is a long reversing track between the Etihad and Velopark stations. This is normally used for reversing trams on the Altrincham-Etihad service.
- Shaw & Crompton – there is one dead-end platform as well as the two through platforms. This is normally used for reversing trams on the Didsbury-Shaw services.
What’s clear to see is that except for Shaw there are no dedicated reversing loops on the Northern side of the City Centre.
That means there’s nowhere convenient to reverse trams without blocking the line to “through traffic”, which causes more delays.
“But what about that third platform at Victoria, the one in the middle?” I hear you ask.
Regular users of the network will be used to this “white elephant”. Installed during the recent Victoria redevelopment, it has rarely been used. I believe it may have been used on one or two occasions during some planned engineering works, but it otherwise sits there, and is never used in normal service. There are even “Tensabarriers” across the centre tracks here, that’s how unused it is.
If this was operational during Friday’s incident then diverting Eccles-Ashton or Altrincham-Etihad trams via 2CC, reversing at Victoria then running via Market St, and regaining their booked route at Piccadilly Gardens might have been possible, but it wasn’t.
There might be very good reasons why it is not used, but these are not shared with us mere mortals. Instead it sits there as an embarrassment.
Trams from the South of the city which are currently shown as terminating at Victoria actually run empty to Queens Road after emptying out – there they have to reverse direction on one of the main lines, either to return South or enter the tram depot at Queens Road. There is no shunting line or reversing siding provided to do this move, and limited space to build one even if there was funding to do it.
There used to be a reversing siding just outside Victoria that would have been useful, but I also believe that to be disconnected/decommissioned and not available for use.
So, in spite of the additional flexibility added by 2CC, there are still some fairly significant constraints facing the controllers, and a big risk of trams backing up.
The redevelopment work for Crumpsall station will provide a new “turnback” facility, which will normally be used as part of the new Trafford Park service, but again provides Metrolink controllers with another useful option on the Northern side of the network when handling disruption.
Anyway, that’s enough for today.
Next time, we’ll find out that despite looking the same not all Manchester trams are equal, and maybe a word or two on power.
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