The London Overground Gospel Oak to Barking line will reopen next week after the installation of new overhead electric lines.

Network Rail said the “transformational, once in a generation upgrade” designed to improve air quality and make journeys more comfortable and reliable for passengers will be unveiled on Monday, January 15.

Last May the route - which runs through Walthamstow, Leytonstone and Wanstead – was closed for works just three months after an eight-month closure due to design blunder.

Commuters faced continued disruption to the service in 2017 to allow for the engineering work to be carried out.

The existing two-car diesel trains will be used until the four-car electric trains have been fully tested and driver training complete in spring 2018.

There will be services every 15 minutes throughout the day until late evening and at least every 20 minutes after 10pm.

Jonathan Fox, Transport for London’s Director of Rail and Sponsored Services, said: “I welcome the return of services to the Gospel Oak to Barking line and would like to thank customers for their patience while Network Rail completed this stage of the electrification works.

“A period of testing of the new electrified line will now take place ahead of introducing new, more reliable and longer electric trains in the spring.”

The work is part of TfL’s improvement plans and Network Rail’s London Railway Upgrade plan aimed at creating new connections and increasing capacity in the peak hour by 30 per cent.

Improvements to the London Overground network are included in the Mayor’s draft Transport Strategy, which aims to improve public transport and reduce reliance on car journeys.

Meliha Duymaz, Network Rail’s route managing director for Anglia, said: “Passengers travelling on the Gospel Oak to Barking line are set to benefit from a transformational, once in a generation upgrade with a new fleet of longer, electric trains so that twice as many people can travel comfortably, once line testing is complete.

“I’d like to say a big thank you to our railway neighbours and passengers for their enormous patience and understanding while we worked to improve this busy London route.”