Remodelling Cricklewood

Next time you travel down to London on the Midland main line, look out of the left hand window as you enter the capital. Depending on the time of day, you will see either a load of trains parked up, waiting for the next peak period, or an expanse of empty sidings.

This is Cricklewood. A large part of the East Midlands Trains fleet seems to be parked here during the day, and that role is due to be expanded as the new Thameslink fleet comes into operation.

There are two sets of sidings at Cricklewood – North and South – which are linked by a scissors crossover. Both were to be extended, but without reducing the existing capacity which is used daily and would have to remain operational throughout the development.

Planning brings success

“The success of the project lay in the planning and the collaboration,” said Carillion project director William Dundas. His Carillion team has worked on a number of depots – Bedford, Selhurst, Brighton and Peterborough – so had the skills learned on previous projects to bring to the Cricklewood project.

The first stage of the project was to remove the northernmost out-of-use section of the North Sidings. This created a brownfield site where the new extension to the sidings could be built. The area had previously been managed by a wood waste broker, which engaged with its supply chain to remove 643 tonnes of wood waste from this area, diverting 100% from landfill.

The new North Sidings has six tracks and a total stabling space for120 carriages. Once completed, so all trains could be stabled there, work began on the 500 metre long South Sidings to create capacity for a further 120 carriages.

All work on the sidings took place while Cricklewood depot was a live operational environment. In order to complete the work required, the overhead lines to the areas over the old sidings had to be removed. Carillion worked with Tata, the scheme designers, to thoroughly plan the isolation arrangements for adjoining lines prior to work commencing. The work wasn’t started until everyone involved in the project was satisfied that the arrangements would provide the levels of safety required to undertake the works.

A question of control

The new site is fully signalled and controlled from Cricklewood Depot signal box, via a new NX panel and RRI interlocking. A new 650V signalling power supply has been provided for the new depot equipment and a new Westronic system, acting as a panel multiplexer and train describer, was fitted within the Cricklewood panel.

The North Connection will be signalled in and out of the Reception line by the West Hampstead signaller via two new sets of points, with an existing signal moved to facilitate moves into the reception line, and a new signal to signal out. The South Connection entry and exit remained essentially unchanged, although the entry signal has historical sighting issues so it has therefore been replaced and a new Banner Repeater provided. Slots have been provided for the signallers at Cricklewood and West Hampstead signal boxes to send and receive trains over the boundary.

Apart from pre-planned weekend possessions the North Sidings remained operational throughout the construction phases of this scheme, but the South sidings were temporarily decommissioned once the North Sidings had been extended to allow their reconstruction for the new layout. As part of the scheme, nine ends of hand points were changed to clamp-lock operation, and were operated under power by the shunter as a local arrangement in advance of the final commissioning; one set of trailing hand points remains as sprung points.

The final commissioning was split over four weekend possessions during June 2015, during which the re-controlled assets from the new Cricklewood interlocking were tested to reduce the time required for the final commissioning and bringing into use.

The two Ss

During the planning phase, Network Rail introduced the Planning Delivery and Safe Working mandate and this impacted the work at Cricklewood.

As well as the challenges trackside, there were also a number of traffic management issues because the site was next door to a scrap metal merchant and other parties used the service road. Project manager Tom McElhatton and team devised a number of traffic management strategies to ensure safety and segregation on site. Large fences were erected to prevent any loose materials blowing onto the track and a speed limit of 5mph was enforced, both to protect the workforce and help prevent traffic accidents. In addition the walking route from Cricklewood station to the site was refurbished to provide a safe, segregated route.

There was an excavation incident on the site which was investigated and led to a new process for excavating on all Carillion Rail sites. Steve Bladen and Ray Rushe developed a video and training programme at Cricklewood to demonstrate how the new safer process works which has been shared across the business. The knowledge gained at Cricklewood has been successfully implemented at Peterborough and Horsham depots.

Sustainability was a key feature of the project and, in addition to the community project, the team also focused on resource efficiency – recycled ballast on site diverting 99% waste from landfill, saving natural resources as well as the benefit of significant cost savings from not having to buy in new aggregate.

Despite the challenges of getting everyone onto the large site at the same time, everyone working on Cricklewood attended a morning briefing every working day. This ensured that everyone knew what was happening on site and there was a greater understanding of what other disciplines were focusing on. It also encouraged the sharing of safety best practice which extended beyond this project to other Carillion Thameslink sites. The level of collaboration with Network Rail was superb and Jim Brown, the Network Rail operations manager, really encouraged the sense of ‘one team’ on this project with the civils, p/way, OLE, signalling and planning teams all working together harmoniously.