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If you’d stood in the doorway of Lower Mainwood Farm at Ringway a century ago, the view ahead would have been green and agricultural. Try the same today – not that I’d recommend it – and you’d probably be wiped out by a Boeing 747. Wrecking balls have long since razed the farm as part of the development of Manchester Airport, its history now buried beneath the north runway’s tarmac. From modest beginnings in the Thirties, the airport now handles more than 22 million people and 170,000 aircraft movements annually, an expansion which has elevated it to become the third busiest in the UK.

Opened in May 1993, the airport’s railway station acts as a key gateway with around 15% of passengers arriving or departing from there. Not surprisingly, the site it occupies is tight – hemmed in by hotels on three sides – and overflying the middle of it is a bridge carrying the dual carriageway that serves the terminal buildings. Called Outwood Lane, this follows the same alignment as it did when Lower Mainwood Farm was still a going concern.

The station was originally built with two platforms, each able to accommodate two four-car units either side of an island. However, service reliability relied on trains arriving in the right order, a reality which brought knock-on effects at Manchester Piccadilly where scarce platform capacity was often absorbed by trains waiting for paths. The installation of a third platform in 2008 largely resolved this, offering much greater operational flexibility.

May 2009 saw plans announced for a Metrolink route to the airport as part of its Phase 3 expansion project, connecting to the existing network at St Werburgh’s Road. Then, in July 2012, the government announced its support for a fourth mainline platform, creating capacity for more Manchester Airport services via the new Ordsall Chord. This forms part of the Northern Hub scheme, bringing more than £1 billion of investment to the North’s rail network. There has also been mooted the provision of a through route, extending the railway westwards – under the airport – to join the Northwich line, but let’s not go there right now.

In partnership

With the intention of trams and trains sharing the same station, it soon became clear that much would be gained by bringing forward the fourth platform’s proposed 2018 completion date, combining the works with those for Metrolink and thus taking fullest advantage of the access opportunities established. Train operators also favoured this approach as it would further enhance the benefits arising from the North West electrification programme. M-Pact Thales acted as designer and principal contractor, its client being Transport for Greater Manchester but with Network Rail using the same contracting mechanism to fulfil its requirements.

ManchesterAirport-093 [online]

The chosen design option – driven by physical and operational constraints – involved constructing the three tracks and platforms along the north side of the existing station on land previously occupied by an embankment up to ground level, the railway sitting in a six-metre deep cutting. Immediately beyond this is an airport building, known as No.4, and the Hilton Hotel which served as limits for the potential development footprint.

From Network Rail’s perspective, this package of work effectively formed Phase 1 and was undertaken during the spring of 2014. Delivered was most of the construction activity for  the new platform was delivered (the need to relocate several location cabinets prevented its completion) as well as the associated rebuilding of Outwood Lane bridge to include a new portal for the Metrolink line whilst extending the existing Platform 3 span to accommodate the fourth platform. This involved the lifting-in of 28 reinforced concrete beams and 11 parapet units whilst 118 wagon-loads of arisings were despatched for recycling. A temporary services bridge also had to be assembled.

The need for a 17-day road closure proved a challenge for all concerned due to its impact on airport access off the motorway network. Possession also had to be taken of Platform 3, with 30-hour blockades needed at the top and tail to dewire and then restore the platform’s overhead line. Despite these complexities, 5,000 trains continued to serve the station using the remaining two platforms and the work was successfully concluded ten hours early.

All together now

Phase 2 has involved fulfilment of the track, signalling, overhead line and remaining platform works, together with installation of the customer information system (CIS) and CCTV. Again, the access strategy was subject to discussions with the airport and train operators, the preferred approach being a one-hit winter blockade – a time of year that would cause the least possible disruption to the travelling public. The station was closed from 17 January to 9 February 2015, with Platform 3 further out of service for the previous week.

ManchesterAirport-029 [online]

Although AmeySersa – delivering the track works – was appointed principal contractor, the project actually adopted an alliance-style hub-and-spoke arrangement with the various firms engaged through Network Rail: Buckingham Group for civils, Siemens for signalling, OCR (Network Rail’s in-house team) for the overheads and Manchester Airport for the CIS/CCTV.

With nothing available close by, the team secured land a mile east of the station through Manchester Airport Group, establishing a compound there in October 2014. This offered sufficient space for offices and materials storage, but would demand a very disciplined approach to workforce management and the provision of minibus shuttles to get them to and from site.

Over the weeks that followed, surveys were undertaken to validate the designs (Parsons Brinckerhoff for track, Mott MacDonald for OLE) as well as regular whiteboard meetings to ensure the robustness of plans for the blockade, with appropriate contingencies. Where possible, progress was made with the installation of concrete bases for the new overhead line steelwork. This took place at Christmas and during the airport branch’s limited Rules of the Route access periods which afford five-hour possessions for four consecutive nights every six weeks.

Hit the ground running

The closure of Platform 3 on Sunday 11 January allowed the team to start work on the careful demolition of a low 300-metre long retaining wall just outside the ballast shoulder, as well as carrying out a deep dig between it and the new fourth platform to make way for the track.

Possession of the remaining station and the branch back to Heald Green North/South junctions was taken over the following weekend, allowing the rest of the wall and the concrete bases for the old OLE steelwork to be removed. Combined with a 30-hour isolation of the Metrolink route, the opportunity was created to crane in a couple of dozen overhead line structures from car parks adjacent to the railway – a contrast to the conventional installation method using roadrailers.

This allowed an early start to the process of changing over the wires and then taking out the redundant steelwork whilst keeping the wires in the air.

Also lifted in was a cantilevered signal gantry from the Hilton Hotel car park to the end of platforms 3/4. On the face of it, this appears hugely over-engineered for its purpose, but it allows testing and maintenance of the signal heads to take place without the need for an OLE isolation.

Time of the essence

Complicating the track work planning was the route’s curvature, the presence of an overbridge 170 yards off the platform end and the ability to approach the site from one direction only.

Getting the timings right for arrival, departure and movement of the 14 engineering trains therefore demanded a sharp focus.

The track and drainage work proceeded eastwards from the new bufferstop, with the panels mostly brought in by tilting wagons to increase productivity before installation was carried out by a pair of Kirow cranes. In terms of layout, the Platform 4 line joins the existing Down Airport via a single turnout just before the overbridge, beyond which is an existing trailing crossover. To provide a route from the Up Airport into Platform 4, new S&C has been established on the curve approaching Woodhouse Lane overbridge. Whilst this created engineering and design issues, the proximity of booster overlap zones for the overhead line made this the optimum location.

image5 [online]

In parallel with the track activity, Siemens staff were running in cables for the signalling and telecoms equipment. To meet current standards, two RA and OFF indicators have been provided on each of the platforms; previously there was only one. The route’s conventional signal heads have also been replaced with LED units from Unipart Dorman. The scheme has involved a data change to the route’s SSI (Solid State Interlocking) signalling but the most complex aspect has been the associated works in Piccadilly Power Box where wiring into the existing system, given its size, proved quite challenging.

Registering the overhead line to the new track alignment occupied much of the blockade’s final week. The wires were installed under tension using Network Rail’s wiring train, the longest run being around 1,500 metres. Again, this approach was adopted in an effort to minimise the amount of disruptive access needed.
The final weekend saw the whole system brought back into use through testing and commissioning; handback came on the morning of Monday 9 February. Platform 4’s first passengers will arrive in May as part of the new Spring timetable.

Different worlds

“Project by project, the upgrades being made to provide a better railway across the north of England are being completed,” insists Network Rail’s Area Director Ian Joslin. “The new fourth platform at Manchester Airport station is the latest example and will contribute to an improved rail service to the airport.”
And it will need that improved service as work on the £800 million Airport City property development gathers pace over the next 15 years, during which time the intention is to offer new office space, hotels, advanced manufacturing, logistics and warehouse facilities on a site north of the station. The promotional blurb describes it as “a vibrant economic hub”, much as Lower Mainwood Farm was a century before.

Photos: Four by Three.

Graeme Bickerdike
Graeme Bickerdikehttp://therailengineer.com
SPECIALIST AREAS Tunnels and bridges, historic structures and construction techniques, railway safety Graeme Bickerdike's association with the railway industry goes back to the mid-nineties when he was contracted to produce safety awareness videos and printed materials aimed at the on-track community. This led to him heading a stream of work to improve the way safety rules are communicated and understood - ultimately simplifying them - for which he received the IRSE’s Wing Award for Safety in 2007. In 2005, Graeme launched a website to catalogue and celebrate some of the more notable disused railway structures which still grace Britain’s landscape. Several hundred have since had their history researched and a photographic record captured. A particular focus has been the construction methods adopted by Victorian engineers and contractors; as a result, the site has become a useful resource for those with asset management responsibilities. Graeme has been writing for Rail Engineer for the past ten years, generally looking at civil engineering projects and associated issues. He has a deep appreciation of the difficulties involved in building tunnels and viaducts through the 19th Century, a trait which is often reflected in his stories.
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