With electrification being high on everybody’s consciousness, the schemes to electrify the Great Western and Midland main lines have been getting all the attention. Similarly, the works in the North West and Scotland have been proceeding apace and gaining publicity but the scheme to electrify the railway from Walsall to Rugeley has managed to stay ‘under the radar’.
The scheme is, in fact, a significant step in the direction of developing the public transport system in the West Midlands by improving services on what was a relatively-forgotten part of the network. Due to be completed by December 2017, the project will allow electric trains to run between Birmingham New Street and Rugeley via the Cannock lines, providing passengers with a more reliable, efficient and greener service.
In fact, the scheme will revitalise a line which, not so many years ago, had no regular passenger services at all.
Closure and reopening
The line from Birmingham to Walsall (sometimes referred to as the Walsall line) has two alternative routes, both electrified at 25 kV AC overhead. One leaves New Street to the east, following the Cross- City Line as far as Aston, where it diverges to the west. The other leaves to the west, and travels via Soho. Beyond Walsall, the line was not electrified, and continues north to Hednesford and Rugeley. This is sometimes called the Chase line, referring to the Cannock Chase area through which it runs at its northern end.
Beyond Walsall, the line to Rugeley Trent Valley closed to passengers in 1965, although it remained open to freight. Despite this, the route was occasionally used as a diversionary route for Inter-City passenger services from Birmingham to Manchester, Edinburgh and Glasgow in the event of the Wolverhampton-Stafford route being shut for Sunday or late evening engineering work.
Passenger services returned to the route in stages:
» 10 April 1989 — Walsall to Hednesford
» 2 June 1997 — Hednesford to Rugeley Town
» 25 May 1998 — Rugeley Town to Stafford.
However, from the 12 December 2008, Chase line trains were withdrawn from running through to Stafford and were cut back to Rugeley Trent Valley on the West Coast main line.
The lines between Birmingham New Street and Walsall were electrified in 1966 as a part of the West Coast main line electrification, together with the Walsall to Wolverhampton line. Electrification of the Chase line was first discussed in the early 1960s, but funding was not secured until February 2013.
In July 2013, the government announced electrification of the line between Rugeley Trent Valley and Walsall, the work scheduled to take place from 2014, with a completion date of December 2017.
Electrification of the line will be accompanied by a speed increase from the historical 45mph to 75mph. The line will also be cleared to W10 loading gauge, allowing flexible use of the line for freight container traffic. As it is intended to run longer trains on the route, station platforms will need to be extended to accommodate them.
Prior to the electrification work, resignalling of the route has been undertaken with the closure of three manual signal boxes at Bloxwich, Hednesford and Brereton Sidings, together with the panel boxes at Walsall and Bescot. Control of the area passed to the West Midlands Signalling Control Centre at Saltley. The resignalling has incorporated renewal of signalling power supplies and associated electrical works.
Service pattern changes will reduce both journey times and overcrowding to Birmingham as journeys will be up to 15 minutes shorter and there will be four trains per hour. Additionally, new services may be introduced to Birmingham International (two trains per hour), Coventry (two trains per hour) and Liverpool Lime Street. Even a direct service to London Euston has been mooted.
The project team
Although primarily an electrification scheme, the project is also about civil engineering work – not only to facilitate that electrification, but also to obtain the linespeed improvements, to enhance the gauge to W10 and to close a few level crossings.
Adhering to the principles of collaborative working, the project team and the contractor are in one office, effecively ‘one team, joint processes’. The scheme is being overseen by senior programme manager Katie Ferrier on behalf of the central electrification team.
This integration supports a joint approach to access planning across the route and the integration of engineering assurance within the Network Rail standards. A fortnightly meeting is held to ensure engineering coordination.
Design meets the philosophy of ‘safe by design’ and is in compliance with the current set of applicable European technical standards for interoperability (TSIs).
The core project covers 51 single track kilometres of electrification including foundations, structures, the contact system and steelwork. The main electrification works are being managed by Sam Evans who joined Network Rail as a graduate five years ago and has been a project manager within the electrification and plant renewals team since 2012.
Design of the new system is being undertaken by Atkins whilst construction is in the hands of the holders of the framework agreement, the ABC consortium of Alstom, Babcock and Costain.
The new electrification is keyed into the existing electrification infrastructure and an early project design and construction challenge is to abut the new auto- tensioned Series 2 OLE system into the 1960s fixed- tension equipment at Pleck Junction, some of which may need to be replaced.
The new equipment will deal with the raised speeds proposed in the parallel linespeed improvement project; the OLE being designed to meet the 75 mph running. Configuration of the Series 2 equipment will be a boosterless classic system with a 12kA fault level. As a novel configuration, this will be the subject of a specific safety case analysis. Cable theft in the area is a significant concern and some novel defence against this crime is proposed.
The distribution side of the project is taken care of by three substations, new installations at Walsall Pleck Junction and Hednesford with modifications to the substation at Brereton.
There is a telecommunications aspect to the works, including a dedicated fibre-optic route for accelerated distance electrical fault protection within the electrical distribution which is allied to the national telecommunications strategy and the national SCADA (system control and data acquisition) project.
Structural foundations will, for the northern end of the line, be of a piled format taking advantage of the productivity of the piling train. However, there is a long history of mining at the southern end and there is a gap of eighty years of missing mining records. To allow robust concrete OLE foundation installation, there is a significant survey workload involving ground proving radar and other relevant methods.
The piling train is provided by ABC and consists of a Kirov crane with ABC’s own piling rig attached; it is anticipated that a rate of three piled foundations an hour may be achieved. Structural erection can be undertaken using a mechanical manipulator, reducing the need for staff to be placed at risk by being close to the worksite and allowing maximum flexibility of construction. Final erection of the contact system wiring will be by the ABC group’s own wiring train and skilled teams.
The Series 2 equipment has proved to be very adaptable to high-productivity erection. Advanced techniques allow the positioning of structures to be fed back to the designer in the office ensuring a level of design accuracy that allows steelwork to be pre-assembled before final erection on the foundation. Auto-tensioning will be of the Tensorex arrangement, avoiding the use of traditional balance weights and bringing live equipment within the curtilage of the OLE structures.
Much emphasis has been placed on productivity and safety during maintenance, and the system will incorporate motorised three postion switches to facilitate isolations and alternative feeding. It is anticipated that the whole line may be safely isolated within half an hour of taking the route.
A separate civil engineering team is managed by Matt Brown, who has a background in bridge reconstruction and became involved with the project in 2013 at GRIP stage 1 (output definition).
The works are composed of four packages:
1. Early works took place in Control Period 4 with three bridge reconstructions undertaken by the contractor Amalgamated Construction (AMCO).
2. There are two sub-packages. Firstly 2A which encompasses Walsall tunnel – undertaken again by AMCO. This work includes the partial reconstruction of a covered way around a main shopping area. Major changes to the track layout are taking place which has rendered the option of track lowering unavailable. It was emphasised that there was no gauging information for the infrastructure at the site. These particular works are being dealt with in three phases to minimise disruption to the service and the stakeholders. Secondly 2B is being undertaken by Murphy covering the two bridges at Walsall and commencing spring / summer 2015.
3. A package of track lowering at eleven sites; the works in this case being undertaken by Stobart Rail.
4. A package covering parapet height upgrades driven by the need for TSI compliance. Construction of this parapet work also being undertaken by AMCO.
The total project scope includes nineteen major interventions with 30 parapet extensions. These latter works tend to arise from a change in emphasis within the Technical Specifications for Interoperability where the specification for parapet height over electrified lines has increased from the traditional United Kingdom norm.
The initial scope of the work included a high percentage of bridge reconstructions, but careful analysis of the requirements and integrated planning with the electrification function allowed a revised view. Experience on the North West electrification programme showed that taking advantage of track lowering opportunities could significantly reduce the need for total bridge reconstruction and this lesson was brought to the Walsall – Rugeley project. As a result, 11 bridge reconstructions were deemed unnecessary and there are now only two in the final scope. This lesson has usefully spread across other electrification schemes, although the specifics of permanent way drainage and contact system gradients have to be taken into account in each case.
The electrification works carry the usual challenge of the United Kingdom where a restricted Victorian infrastructure is being adapted to modern railway use; clearances being very restrictive and the need to observe TSIs influencing clearances and compliance works. Behind the decisions to undertake track lowering were the robust condition of most bridges suggesting excessive works would be wasteful of scarce investment funds. There has been no intention to use the alternative of bridge jacking within the scope.
A separate but related project is in progress to close Bloxwich level crossing to motorised traffic, accompanied by one of the retained bridge reconstructions, enabling the current 20mph line speed limit to be lifted.
In Matt’s view, the greatest challenge is “the best fit between bridge reconstructions and track lowering and selling the solution to the infrastructure managers in the route.” Consultation has resulted in a positive and productive relationship with the route asset managers’ teams and a real understanding of the whole life cost issues.
The electrification of this West Midlands route has emerged as a positive illustration of the new electrification design and construction methodologies. The experience gained will be fed into the many similar schemes now being proposed to expand the electrified portion of the United Kingdom rail network.