01.11.11
Behind the curve - The Ordsall Chord is a poor choice
Peter Johnston, Rail Services Officer with responsibility for rail timetabling and operations at GMPTE from 1993 to his retirement in 2005, devised and wrote the Passenger Service Requirement Specifications for the Greater Manchester local rail network at the time of privatisation. Here he argues that the Ordsall Chord proposals are unlikely to increase capacity as much as claimed.
History and context
The present context of rail operations in central Manchester was established in 1991. Before that date, there was little cross-city working and Manchester had effectively two separate networks, based respectively on Victoria and Piccadilly stations.
Services from Blackpool, Blackburn, Windermere and Barrow-in-Furness operated into Manchester Victoria, and south side services operated into and through Piccadilly. A limited Transpennine service from Liverpool to Newcastle-upon-Tyne or Hull operated via the Chat Moss route, Manchester Victoria and Stalybridge with a free-standing service of seven or eight trains per day between Stockport and Stalybridge in each direction providing a link between North-South and West-East services.
In 1991, the Windsor Link was completed and opened. This ran from Windsor Bridge Junction and the newly-constructed Salford Crescent station to Ordsall Lane Junction, and together with the existing link from Ordsall Lane Junction to Castlefields Junction enabled services from Blackpool via Preston and Bolton to operate to Deansgate, Oxford Road and Piccadilly, providing an improved direct linkage into principal North-South services. For operational convenience this service was linked to the existing Piccadilly – Buxton service.
At the same time Transpennine services from Liverpool were switched from the Chat Moss route to the CLC route through Warrington Central, and operated directly through Piccadilly via Ardwick Junction to Guide Bridge and Stalybridge, continuing to Leeds and York, and Scarborough, Middlesbrough or Newcastle. A second hourly fast service from Liverpool took the same route, continuing via Stockport, the Hazel Grove chord line and the Hope Valley route to Sheffield, Nottingham and East Anglia. Patronage on the Stockport – Stalybridge service dropped to negligible proportions, and this service was subsequently reduced to the Parliamentary minimum of one train per week in one direction only.
A spur from Heald Green on the Styal line to a new station at Manchester Airport opened in May 1993, enabling the development of a range of direct services to Manchester Airport from Liverpool, Southport/Wigan, Blackpool, Barrow-in-Furness and Windermere as well as Transpennine services from Newcastle, Middlesbrough, and Scarborough via York and Leeds. The pattern was fixed in its present shape when Transpennine Express took over the provision of regular services between Manchester and Edinburgh/Glasgow, extending the service backwards to Manchester Airport.
Analysis
There have been in total three consultancy reports within the last 20 years, the most recent of which was commissioned by the Regional Development Agencies involved, under the banner of the Northern Way. All offered a range of broadly similar solutions involving additional through platforms at Manchester Piccadilly, on or adjacent to the Mayfield station site, additional track capacity from Piccadilly to Slade Lane Junction upgrading the existing down goods loop, a grade-separated junction at Ardwick and the construction of a west-to-east curve from Salford Central station to Castlefields Junction with grade separation (optionally) at Ordsall Lane Junction, to enable trains from Manchester Victoria to access the link from Castlefields Junction through Deansgate, Oxford Road and Manchester Piccadilly.
The common feature of all analyses is the key limitation of track and platform capacity on the section between Castlefields Junction and Manchester Piccadilly, and the crucial limitation of the four minutes ‘platform dwell and reoccupation time’ on the through platforms 13/14 at Piccadilly provided under Rules of the Plan.
For severely practical reasons, this applies to all trains except a single local suburban service from the south terminating at Deansgate, and means that a total of 12 train paths per standard hour in each direction is the maximum which can be accommodated. All of these are presently taken up. It follows that no additional services can be accommodated unless the option of providing additional through platforms at Piccadilly is taken up, or some existing services are removed. The consequence of creating two additional through platforms at Piccadilly on the Mayfield site would be to increase the number of permissible through paths per standard hour in each direction from 12 to 19 or 20 train paths.
Implicit in the decision to authorise the Ordsall Chord is the long-held desire of network access planners to remove the Liverpool to the North East Transpennine service from Piccadilly and the CLC route and transfer it instead to the Chat Moss route and Manchester Victoria.
Similarly there is a wish to transfer the Newcastle/Middlesbrough to Manchester Airport services which presently reverse in-platform in the main trainshed at Piccadilly and instead to run them via Stalybridge, Manchester Victoria, the Ordsall Chord, Castlefields Junction and Piccadilly.
The immediate consequence of removing the Liverpool service from Piccadilly would be to vacate a single train path per standard hour in each direction from the Castlefields-Piccadilly link, and halve the fast service between Liverpool, Warrington Central and Piccadilly. If this vacant path is used to accommodate an hourly Calder Valley service extended from Manchester Victoria via the Ordsall Chord to Manchester Airport, any replacement Liverpool – Manchester fast service on the CLC route will not be able to run east of Oxford Road, since the principal bottleneck on the Northern Hub is not between Victoria, Salford Central and Ordsall Lane Junction, but between Castlefields Junction and Ardwick Junction: we must assume that Network Rail are less interested in developing cross-Manchester capacity than in getting the Transpennine services off the throat of Piccadilly station.
The other consequences of transferring Transpennine airport services to run via Manchester Victoria and the Ordsall curve are likely to result in 12 minutes or so additional journey time for through airport passengers, by comparison with in-platform reversal at Piccadilly, and – were access planners similarly to divert the East Midlands Trains Liverpool to East Anglia service to travel via Manchester Victoria, Stalybridge (with reversal in-platform) thence Denton and Heaton Norris Junction – even larger additions to end to end journey times. This would then allow a second hourly Calder Valley service to extend to Manchester Airport.
The only obvious benefit therefore would be to liberate fast-line paths into the main trainshed at Piccadilly. Since platforms 1 to 4 are fully occupied by Eastern side services to Marple, New Mills, Sheffield via the Hope Valley, Glossop and Rose Hill, and Transpennnine services from the North East to Manchester Airport, and platforms 5 to 9 are almost exclusively occupied by Virgin West Coast and Arriva Cross Country, platforms 10 to 12 can accommodate Crewe and airport locals, mid-Cheshire lines and Buxton services. It is difficult to see what else could be accommodated, especially since platform 12 can only accommodate three-car units. The only short-term expansion presently under consideration is the expansion of Virgin West Coast services from three trains per hour to four.
In the medium term, it may be possible to free up some capacity by converting Marple or Glossop services to tram-train, but this is not entirely easy to bring about, partly because of the disparity in vehicle capacity between a two-car tram-train (or even two of them coupled together) and the three-car electric trains presently operating the Glossop service, and partly because of limitations of on-street capacity. Further, a Marple tram-train operating on low-voltage 750-volt overhead electrification would have to go on-street somewhere east of Ashburys to avoid conflict with the existing 25kV electrification on the Glossop line, which might well form part of future Transpennine electrification from Guide Bridge via Stalybridge to the Diggle route.
Clearly, there are certain choices to be made, and a number of problems identified below, which need to be addressed. One problem is that, in some quarters, tram-train is seen less as a means of improving the operational performance of the local rail network, than as a means of facilitating other ambitions at minimal cost.
In particular, it has been a favourite aspiration of Network Rail’s access planners to get the dross away from the throat of Manchester Piccadilly, at whatever cost to the local network, the more readily to facilitate the movement of bigger, more important trains to bigger, more important places. This has been a fundamental principle of train planning at least since the days of the London & North Western Railway.
Electrification vs alternative forms of traction
Diesel traction is a second option. This has the advantage of not requiring the provision of new overhead line equipment, and the disadvantage that interworking with existing Metrolink services into the city centre would increase noise and pollution, and might encounter future cost penalties dependent upon the behaviour of world oil prices. It is unlikely to be environmentally acceptable.
A hybrid electro-diesel option with diesel power being used for those sections of route not electrified is similarly an alternative, and suffers the twin disadvantages enjoyed by purely diesel traction and the weight and performance penalties of having a dual power system on board.
Route options for tram-train conversion
By far the most obvious, and the most suitable choice would be the mid-Cheshire line from Chester via Northwich to Altrincham, where it could join end-on with the existing Metrolink line, to give improved access from mid-Cheshire and Hale to central Manchester destinations.
For Wigan – Wallgate to central Manchester there are two specific problems. To avoid existing congestion on all routes inbound from Salford Crescent it would be necessary to go on-street or provide a new alignment from this point. It is not easy to see how this could be integrated with existing Metrolink provision, and when Phases 3a and 3b of Metrolink are complete, it is unlikely that the network could accommodate any additional tram-trains, at least pending completion of the second city crossing.
Likewise given existing levels of congestion on the A6 in the Salford Crescent area, it is unlikely that an on-street alignment could be provided without profound disruption to existing traffic flows. The distances involved, by comparison with other candidate routes, and the lower speed obtainable with tram-train vehicles, by comparison with conventional diesel units, suggest that conversion would result in an extended journey time by comparison with existing heavy rail, and the need to go on-street as far out as Salford Crescent would similarly extend end-to-end journey times, perhaps in combination by as much as 20 minutes. This could result in the transfer of through passengers to other routes between Wigan and Manchester via Bolton. Not recommended.
Conclusion
Investment in the Ordsall Chord, unless accompanied by investment in additional through capacity at Piccadilly, would seem a poor choice, and indeed by this reckoning is quite the least important element in the Manchester Hub proposals. One may only conclude that it is being given priority for other than the publicly stated reasons. On any rational calculation of investment and benefits the Ordsall curve would appear to offer only limited scope for increasing capacity, by comparison with the additional through platforms for Piccadilly.
Ordsall Chord timeline
Autumn / Winter 2011: Consultation on outline scheme
Spring / Summer 2012: Consultation on detailed designs
Winter 2012/2013: Consultation on draft application
Spring 2013: Submission of final scheme to the Infrastructure Planning Commission (IPC)
Spring 2014: Application to be determined by the IPC
Winter 2016/2017: New Ordsall Chord to be operational