TfL Confirms Updated Timeline for Gallows Corner Flyover Renewal

Transport for London (TfL) has announced a revised schedule for the renewal of the Gallows Corner flyover, confirming that the major refurbishment project is now expected to be completed by spring 2026.

Under the new plan, the flyover will reopen to general traffic first, followed shortly after by the full reopening of the roundabout and surrounding roads. For now, the junction remains closed to all vehicles except emergency services, black cabs, and TfL buses as work continues to strengthen and modernise the ageing structure.

Originally installed in the 1970s as a temporary measure, the flyover is undergoing a full-scale overhaul to ensure its long-term safety and reliability. Once finished, the improvements will allow the removal of existing speed and weight restrictions, enhancing both safety and journey times for drivers.

Ground Challenges Delay Progress

The project has faced setbacks due to unexpected ground conditions encountered during excavation. Engineers discovered pockets of unstable shale, making the original tunnelling method unsafe and affecting the diversion of a 36-inch water main — a critical piece of infrastructure that pre-dates the flyover and sits within its foundations.

This diversion is essential before new bridge structures can be installed. As a result, TfL, Essex & Suffolk Water (ESW), and contractor Costain have collaborated to redesign the project and reprogramme the works to keep the scheme on track.

Three-Phase Revised Programme

The updated plan will now be delivered in three phases:

Phase One: Completion of bridge sections over the roundabout and installation of the adjacent section of the new water main.

Phase Two: ESW will continue water main installation east and west of the roundabout, navigating three culverts beneath the structure. At the same time, Costain will complete foundation works and add the final bridge sections at the eastern end. Waterproofing and surfacing will follow, enabling the flyover to reopen to traffic by spring 2026. Access to the roundabout will remain restricted during this phase.

Phase Three: Final diversion and commissioning of the new water main, along with highway improvements on the A127and grouting of the redundant pipe. Once this stage is complete, the roundabout and nearby roads will fully reopen.

Visible Progress So Far

Work on site continues to advance steadily. Nine of the 13 bridge sections have already been installed on the western side of the flyover, and foundation preparation at the eastern end is under way. Earlier this month, a new bridge span was erected, marking a visible step forward in the project. The first phase of the water main installation has also been completed, allowing engineers to switch traffic and open up more of the roundabout for ongoing works.

TfL and ESW are coordinating their efforts to replace the water main — a vital supply route for north-east London — in tandem with the flyover renewal, helping to reduce future disruption to the local road network.

Complex Coordination and Additional Obstacles

The delay in completion stems from a combination of technical and logistical challenges, including difficult ground conditions, intricate scheduling between the two overlapping projects, and the discovery of two previously unmapped gas mains that required redesigning sections of the works.

Voices from the Project

Scott Haxton, TfL’s Director of Capital Delivery, said:

“We’re extremely grateful to residents and businesses for their continued patience during these essential works at Gallows Corner. We understand how disruptive this has been, and we’re working closely with our partners to finish the project as quickly and safely as possible. Once complete, the renewed flyover will be safer, more reliable, and will better serve East London for years to come.”

Alastair Tawn, Head of Integrated Delivery Services at Essex & Suffolk Water, added:

“We recognise how important this junction is to local people and road users, and we’re sorry for the inconvenience caused. Our teams are making strong progress under the new schedule, and we remain committed to completing this complex project safely and efficiently alongside TfL and Costain.”

Marcus Hollan, Senior Project Manager at Costain, commented:

“We appreciate the understanding shown by the community as we continue delivering these vital improvements. Our teams will be working extended hours, including through the Christmas period, to complete the additional works without compromising on safety or quality.”

TfL said more detailed completion dates for each phase will be published early next year.