Striking the right chord

Here’s a big question: what’s the point of public transport? If you serve punters at the Tan Hill Inn (Britain’s highest pub) or kick a ball in the Premier League, you probably can’t see one. But sidestepping broader social issues, the population’s remaining 99.999% must surely just aspire to get from A to B in the quickest possible time. Writes Graeme Bickerdike

You might wonder then what possessed our transport planners to sever the Todmorden curve in 1972, compelling the townsfolk of Burnley to travel via Hebden Bridge – four miles in the wrong direction – when the bright lights of Manchester beckon, changing trains there to head back over the same bit of line and adding an unwelcome 20 minutes to their journeys.

But that’s a wrong that will soon be righted. Costing £9.6 million, a project to relay the curve is reaching its fruition thanks to the collective efforts of Network Rail, Northern Rail, the Buckingham Group and Burnley Borough Council, the latter having secured an £8.8 million Regional Growth Fund (RGF) package to deliver this longstanding objective, together with regeneration of the Weavers’ Triangle adjacent to Burnley Manchester Road Station.

So the next winter timetable will see the introduction of an hourly Blackburn-Manchester service – via Burnley and the new chord – giving next season’s Premier League glitterati no cause to power-up their Bentleys to reach Turf Moor from Cheshire. Not likely but hey, worth a shot.

On its face, this looks like a straightforward scheme involving less than 350 metres of new railway. The reality has – as you would expect – been rather different, not least because the granting of that RGF money came with a time limit by which it had to be spent. This triggered what might be described as a GRIP-light process, the aim being to fast-track the development work. Sounds great, but the search for a single option – particularly in relation to the signalling – was complicated by numerous physical and operational constraints.

Degree of difficulty

The Copy Pit route (FHR6) towards Burnley, used by York-Blackpool trains, diverges from the trans-Pennine Leeds-Manchester Victoria line (MVN2) at Hall Royd Junction, half-a-mile east of Todmorden Station. About 90 yards off the platform end towards the junction is a seven-span viaduct, extending for 165 yards, immediately to the east of which is the embanked triangle of land that formerly hosted a chord along its western edge, offering southbound Copy Pit traffic a route towards Manchester.

Standards have evolved a bit since this railway was originally engineered in 1849. Although Northern Rail’s operational preference was for a new two-track chord, there was no room to accommodate a double junction off the end of the viaduct whilst maintaining today’s prescribed minimum radius of 180 metres around the curve. Given its history of movement, the S&C and track alignment design – fulfilled by Atkins – had to ensure that nothing more than maintenance-level tamping was required on the viaduct itself.

Together with the high costs associated with a double junction, this tipped the balance in favour of a single- track chord, with Up trains travelling over the viaduct on the Down line to reach a crossover between it and the station. Locating the crossover here obviated the need for a considerable slewing of the main line – upwards of two metres – whilst further p-way design iterations ensured no works were needed to the station platforms. All this, though, has an implication given MVN2’s limited capacity: in order to accommodate the proposed hourly service, trains using the chord will have to stop at the exit signals before getting the route.

Two alternatives emerged for the position of the junction signal onto the chord from the Manchester direction. The first was to place it on the Down platform at Todmorden but this would have involved extending the platform at its southern end as otherwise there was insufficient space for the overlap. This came with a hefty price tag.



The other option was to relocate a signal on the approach to Dobroyd crossing – quarter-of-a-mile south of the station – to a position 100 yards beyond it. This simplified the interlocking works but necessitated the crossing’s closure as it would have been obstructed by any train standing at the signal.

A bridge too far

All in all, the chosen solution was born of compromise and pragmatism – not perfect, but affordable and all parties agreed that it would work. There was then, of course, the small matter of delivering it. In the project’s early days, the anticipated completion date was somewhat fluid but things firmed up early in 2013 when plans were agreed for a 20-week blockade of the Copy Pit route to allow the partial rebuilding of Holme Tunnel (issues 109 and 113, November 2013 and March 2014). This window of opportunity would define the limits of any disruptive impact the work could have on FHR6.

The Buckingham Group had been involved from the outline design stage through its Multi Asset Framework Agreement (MAFA), the philosophy being to ensure early contractor input which helps to drive out inefficiencies. The design-and-build phase got underway with site mobilisation last summer, although the chord’s alignment had by then been deveged and treatment begun on an infestation of Japanese knotweed. This meant that the track could be laid early doors, alongside which a lit walking/troughing route was installed – using Trojan TroTred – to ensure that drivers were able to change ends safely when the chord was used as a turnback facility.

For the workforce, access into the triangle – with live railways on two sides and a 10-metre drop off its third – involved a regime of regular line blockages arranged with the good folk at Preston PSB to coincide with the start and end of each shift, as well as meal breaks. This was far from ideal for either party but, given the traffic levels and sighting issues on the lines that had to be crossed, something had to give and the alternative, a temporary footbridge, had little to commend it from a financial perspective.

Creeping scope

The longstanding intention with Stansfield Hall Junction, where the north end of the chord connects with FHR6, was to subject it to heavy maintenance. However, the Holme Tunnel blockade brought a late decision to fully renew the junction instead, thus resolving a geometry compliance issue with it and minimising the disruption resulting from future maintenance needs.


That was last September; the blockade ended in March. Procuring S&C can sometimes take three months. Such tight timescales prompted a splitting of the workload: Buckinghams with Colas Rail, the signalling designers, looked after the repositioning of signals and the telecoms activity whilst Network Rail’s S&C Collaboration Team, based in Crewe, fulfilled the track installation, point heating etc using their contractor, Babcock Rail. The tricky interfaces involved did not prevent the work’s completion in time for Copy Pit’s reopening, despite the project having to accommodate the late requirement for a commissioning-weekend measurement train which prompted some hasty replanning.

On MVN2, the team took advantage of two 50-hour weekend possessions in November, first to install the crossover and then the turnout onto the chord. Power supply equipment for the signalling was commissioned during a possession in February whilst March saw another secured to plain-line, a crossover close to Hall Royd Junction, used as a turnback facility but made redundant by the new one adjacent to the station. The still-in-situ interlocking for the long-gone Eastwood loop was also recovered; the space it occupied was needed to host the Westpac relays associated with the new curve. Adapting this ageing geographical technology to meet the specific requirements here – and comply with modern standards - has proved a difficult one to crack, resulting in the signalling design undergoing a lengthy period of evolution.

To mitigate the chord’s impact on capacity – a real concern for Northern Rail – another belated addition to the scope has involved the respacing of signals between Todmorden and Summit Tunnel to address their non-compliance and create additional signal sections. Dorman’s lightweight LED signals have been used across the scheme, ten in number and delivering benefits in terms of installation, cost and ongoing maintenance.


And then there’s the new footbridge. Sorry, didn’t I mention that? Previous usage surveys suggested that Dobroyd crossing was visited only by occasional dog- walkers; nobody expected any great issue with closing it. But due diligence demanded that another survey was conducted, with the crossing being monitored by CCTV around-the-clock for ten days. Initially the team didn’t believe the results: they suggested peaks of 150 users daily, most of them being children. Only then did it become clear that an activity centre had opened at nearby Dobroyd Castle in 2009 and the chosen route to get groups up there was over the railway. This launched the crossing’s risk assessment score into the north-west’s top ten.

There was then no option but to bridge the gap its closure would create. The Kier Group was contracted to install the new structure under the auspices of the National Footbridge Team, completing the work early in March 2014 and bringing it into use at the end of April, coinciding with the signal being moved from its approach side to beyond it. The safety benefit to all crossing users hardly needs stating.

Game-changer

This hasn’t been an easy one. Time, cost and infrastructure constraints, together with the complexities of applying Westpac geographical interlocking to a chord junction, have confronted the project team at every turn, and they continue to do so as the clock counts down. The chord became available for timetabled turnback services in May, with some works continuing on the interlocking to deliver enhanced functionality prior to through trains using it from December.


And then there have been those spanners. “It’s been something of a recurring theme with this job: late changes have been the biggest challenge”, reflects Rob Grey, Network Rail’s scheme project manager. “There’s been plenty for us to cope with. But the new service will encourage growth in the Burnley area. This is a really positive scheme – it will make a huge difference.”

That’s the point of public transport.

Photos courtesy of Four by Three




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