Brent Cross Cricklewood is an ambitious growth and regeneration project that will effectively create a new sustainable town in north London. The scheme includes the construction of a new station, Brent Cross West, to provide a quick connection to Kings Cross St Pancras. Amey acquired the contract to develop essential infrastructure for the station project following the collapse of Carillion in January 2018.
The works centred on the relocation of a set of sidings, which had to be moved to make way for the new station. The infrastructure project included designs for three relocatable equipment buildings plus a tarmac road, signalling and telecoms cable routes, an auto transformer feeder route, siding and mainline signals, driver walkways and an overhead line equipment (OLE) switch walkway.
This was a complex multidisciplinary project which involved close collaboration with Network Rail, Arup (responsible for track and OLE), Amey Consulting’s specialist suppliers and its client, Amey Rail, who would be handling the construction. It was essential, for example, that electrification works did not clash with work on the physical structures or track. Amey Rail’s construction engineering manager coordinated the process, ensuring that the design and construction aspects worked seamlessly together. Also helpful was the presence of staff who had transferred to Amey from Carillion, bringing with them invaluable knowledge of the site.
The project was required to comply with building information modelling (BIM) Level 2 standards. A federated model was built to enable robust design integration, maintained by a dedicated Amey Consulting BIM manager.
In line with Amey’s flexible, creative approach, the Brent Cross team found various innovative ways to cut costs, save time and solve problems. For example, footings were designed to allow concrete to be poured in one go, rather than laying down a sub-base followed by a concrete layer. Discussions with the local infrastructure manager identified existing under track crossings that could be used for running services, saving the expense of installing new underground pipes. Walkways were designed to integrate where possible with existing foundations from old sheds, removing the need to dig out redundant concrete bases. To reduce carbon emissions, concrete was reused wherever possible across the site.
A good example of positive collaboration was the issue of culverts, which arose as the project progressed. It was discovered that several large, aged culverts in unknown condition were located up to seven metres below the site of the sidings. Amey worked with Thames Water to identify the state of the culverts and take the necessary action to cap any that were clashing with the relocation of the Sidings.
It was important that the works did not disrupt the operations of the train and freight operating companies using the existing sidings. Amey Rail developed a comprehensive construction strategy to comply with this requirement, which for the signalling alone involved 19 stages requiring design support. Amey Consulting drew on its pool of experienced signalling engineers to address the design implications of each stage, working closely with Amey Rail’s testing and construction managers. This partnership was instrumental to ensuring the safe operation of the infrastructure throughout the process.
This is the kind of multidisciplinary project where good relationships and informal channels of communication are vital to solving the challenges that inevitably arise. Amey Consulting’s project manager spent two days a week on site to help establish a collaborative working environment. A positive, easy-going ethos was created that made it possible for any team member to pick up a phone and chat to their opposite number in Network Rail or other project partner.
Network Rail’s capital delivery director commented: ‘The tight spatial constraints, tricky cross-party interfaces and tired existing assets make this a tough deliver – and therefore all the more well done! Another great result for Amey … who never seem to be beaten by even the toughest of multidisciplinary undertakings.’