Against a backdrop of constrained funding, local authorities are under pressure to maintain and renew highways networks in a way that maximises budgets while minimising disruption to the travelling public. Too often, these twin pressures are at odds with each other, requiring innovative thinking to deliver essential infrastructure works quickly, safely and without escalating costs.
Transport for London (TfL) and CONWAY AECOM – FM Conway’s joint venture with AECOM – recently faced this dilemma on a major refurbishment scheme for Staples Corner Flyover on the A406, one of London’s busiest roads. The flyover is located at a busy intersection with the A5, just south of junction one of the M1 and west of Brent Cross Shopping Centre. The structure carries over 100,000 vehicles each day so the potential disruption that could be created by the vital upgrade works was significant.
Through meticulous planning and a novel approach to community liaison, we were not only able to keep disruption to a minimum, but also reduce the scheme’s overall timings and budget. It’s an approach that other local authorities and their highways construction partners can and should learn from to drive benefits both for public sector teams and their constituents.
Down to the minute
Delivered under CONWAY AECOM’s London Highways Alliance Contract with TfL, the project brief was technically challenging. It covered the replacement of two 22-metre steel joints that hold the central portion of the flyover in place to extend the structure’s lifespan for an additional 25 years, alongside associated resurfacing works, drainage maintenance, carriageway lining and signage. Given the comprehensive nature of the works, several options were considered in terms of the methodology for delivering the scheme, both to avoid disruption for the flyover’s many users and to protect the safety of workers and drivers.
Initially, the project was planned to be delivered over 57 nights in four-hour working windows, closing the flyover in one direction with an additional lane closure on the opposite side to create a safety zone.
Quite quickly, however, it became clear that this approach had the potential to cause a major headache for regular users of the route as well as adding to delivery costs. Using LEAN principles, we looked again at the brief and constraints around the project to identify an alternative solution.
Critically, in TfL we had a willing partner with which to consider alternative options – enabling us to undertake shorter, intense periods of activity rather than a long programme of partial closure. Detailed planning was key. We carefully mapped out each stage of the works, making sure that every moment was maximised.
As a result, we were able to radically cut back the original programme, opting for just a single week of night-time lane closures for enabling works, followed by full closure of the flyover over two weekends.
Informing road users
Concise programming was just one half of the story. Early on, we recognised that success of the new approach would rely on providing effective advance warning to road users to mitigate disruption to their journeys – allowing drivers to plan alternative routes well in advance.
The scale of the project and significance of the route meant that we needed to use multiple media channels to widely publicise the closures and to cooperate with a range of external partners to get the message out. The scheme was advertised on local radio, through online adverts in the London press and across 18 variable message signs strategically positioned on TfL’s and Highways England’s networks.
This approach was backed up by two public liaison officers who kept key stakeholders informed, including the London Boroughs of Brent and Barnet, Brent Cross Shopping Centre, local businesses like Ikea, and London Buses. In total over 22,000 letter drops were made to local residents to make them aware of the project.
The road to success
This close collaboration ensured that the scheme was a success, delivering a structure that will be fit for purpose for the next 25 years. Crucially the leaner approach selected for the project also saved money and required 488 fewer working hours. Over the entire period of the works just 12 complaints were received about delays – a remarkable feat for such a complex engineering scheme.
John Holliday is contract director at FM Conway
