Transport for London (TfL) has announced plans to refurbish the flyover, which was initially built in the 1970s as a temporary structure.
The flyover is now in poor condition and requires major strengthening and refurbishment to continue operating safely, TfL said.
The project will ensure the long-term safety of the structure and allow for the removal of current speed and weight restrictions.
Scott Haxton, TfL’s director of capital delivery, said: “This complete refurbishment of the ageing Gallows Corner flyover is essential to ensuring that the road network in Havering and beyond can continue to operate safely and effectively for years to come.”
The first phase of the project will see lane closures from March 10 until June.
New pedestrian and cycle crossings will also be installed to make it easier and safer for people walking and cycling, while improved road markings and resurfacing aim to improve journeys for motorists.
From June until September, TfL says there will be a full closure of both the Gallows Corner junction roundabout and flyover to all traffic except emergency services and buses.
From September, there will be overnight lane closures at Gallows Corner roundabout for resurfacing works when the flyover will remain open.
Mr Haxton added: “We’ve worked to minimise disruption as much as possible and are advising people to plan ahead for any journeys in the area.
“We’d like to thank residents for their patience while this vital work takes place.”
