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Northam junction S&C success

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Northam Junction is located in the heart of Southampton, close to St Mary’s Stadium, home of Southampton FC. It links the Basingstoke to Weymouth main line with the branches to Portsmouth and the harbour, as well as with Siemens’ Northam Traincare Facility.

The junction provides crossovers between Up and Down Fast, Up and Down Slow lines as well as access into Siemens’ depot. It is a very intensively used junction with 335 passenger trains, 66 freight trains and 48 empty coaching stock services passing through every day, equivalent to three trains a minute, 24 hours a day, every day.

The railway reached Northam as long ago as 1839, but last Christmas the site of the former Northam Road station witnessed one of the network’s most intensive ever S&C replacement projects.

Local closures

Network Rail had been monitoring the condition of the infrastructure through this junction and had determined that 14 sets of S&C, together with 200 metres of associated plain line, were worn and in need of renewal.

Delivery of this project was recognised as being a major logistical challenge, given the constrained nature of the site, the urban surroundings and the volume of train services that would be affected. This £8 million project was delivered by a dedicated team from the S&C South Alliance and was led by Kev Hoar, Project Manager for Wessex, based at the Bristol office and supported by a wider team from various departments spread through the Alliance and Network Rail.

A piecemeal replacement of this infrastructure over a period of years would have been very disruptive, and so the decision was taken to replace everything in one operation. The works were planned to take place over the now traditional rail engineers’ Christmas holiday, but in this case extended to nine days in total.

The line between Southampton Central and Southampton Airport Parkway was closed, as were St Deny’s, Bitterne and Swaythling stations, and services on the West Coastway line (west of Fareham) started and ended at Woolston. Rail replacement bus services were provided to cover these routes, with 371 trips in total.

The Mount Pleasant Road level crossing was within the work area and was closed, with local road diversions in place.

With this level of disruption to services, it was essential to publicise the works in good time to ensure that those affected would be aware and could make appropriate plans for their journeys over the extended Christmas break. Advance publicity at stations, on trains, and through local media, together with liaison with local authorities, businesses, Southampton Airport and local MPs, began two months before the project commenced and continued throughout, until the works were completed.

The urban location of the works and the nine day, 24 hour nature of the works meant that communications with nearby residents and businesses would also be vital to reduce the risk of disruption and complaints. Kev’s team began communications as long ago as August 2017, with local letter drops that provided details of the works, times of work, precautions being taken to minimise disruption and point of contact in case of queries. This proactive approach paid off for the team, with only a single complaint being received on site, and that only regarding a misaligned work light.


The replacement of the 14 S&Cs was designed by AECOM and was essentially like-for-like, with minimal change to alignment or geometry, apart from one set (504) that lay within a transition and was moved 20 metres towards Southampton.

The two sidings of the nearby Bevois Park freight depot were each extended by 60 metres, providing additional capacity to the yard and also facilitating the project by allowing longer engineer’s trains to be stabled.

The long duration of the project proved a logistical challenge, not least in mobilising the large team of machine operators, supervisors and technical trades that was required. Teams of up to 100 per shift worked a total of around 25,000 hours, with a team of 250 people covering three shifts each day over the nine days. Colas, as Alliance partner, carried out the permanent way works and VolkerRail undertook the signal testing. These were supported and managed by Kev’s team of managers from the S&C South delivery team based in site offices established in the Bevois Park yard.

During the end of October and beginning of November, rails and cables were delivered onto the site. Rails were placed in the four-foot as cesses were very tight through the site.

The new S&C was manufactured by Progress Rail Services works at Darlington. This was broken down for delivery and transported by road to Bevois Park during November, where it was assembled and loaded to engineering trains by a Baldwin Liebherr 1000t crane.

Efficient delivery

On 9 December, plant, lighting and small materials were delivered into the worksite in preparation for the blockade. The following weekend saw the replacement of the lead (513) at the south end between the Up Slow and Up Fast lines. This had to be dealt with separately as its inclusion in the blockade would have disrupted train movements and extended the duration of the works beyond the allotted nine days.

The blockade itself began at 01:00 on 24 December. In addition to the large workforce already described, the project included a Kirow 1200 crane, 25 engineering trains and 16 RRVs.

The intense activity within a confined area was made possible by the detailed planning of the S&C Alliance team and by careful management of the works and vehicle movements. The management team reviewed progress on an hourly basis and adapted the plan where necessary to maintain progress and certainty of delivery.

This was assisted by detailed pre-planning, during which programme certainty was checked using Pertmaster programme risk analysis, run three times rather than the usual once. Each time, the result exceeded the 90 per cent certainty of on-time completion required by the DWWP (Delivery of Works Within Possessions).

This predicted result was borne out in practice, when the team handed the site back 90 minutes early at 02:30 on 4 January. In addition, the project was handed over to traffic at a TSR (temporary speed restriction) of 60mph as opposed to the planned 50mph, and was handed back to the maintainer on 16 January.

Northam junction was one of the largest S&C replacements delivered to date and, as a result of the detailed planning and efficient delivery, has been seen as a complete success by the industry. Kev’s S&C alliance team’s work over the last 15 months was certainly vindicated and they will repeat this in the Christmases to come, at Westbury and Cardiff.

At the end of this project, Kev said that he “saluted everyone involved and their attitude, which was a real testament to collaborative working between all parties in the scheme; from management and works planners to the guys on the ground making it happen”.

The project team’s work on the project, and in particular its consideration for the site’s neighbours, was recognised after completion when it received Network Rail’s ‘Achieving Communications Excellence’ for ‘best example of comms transformation’.

This article was written by Bob Wright. 

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Bob Wright
Bob Wrighthttp://therailengineer.com
SPECIALIST AREAS - STRUCTURES, RAILWAY INFRASTRUCTURE. Now retired, Bob mainly worked in general contracting with May Gurney, and latterly Kier, and was involved with various Network Rail structures frameworks. For the last 40 years Bob has been a voluntary civil engineer on the North Norfolk Railway, latterly as Director. He also acts as a consultant to a number of other preserved railways.



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