Balfour Beatty, Carillion and VolkerFitzpatrick are in contention to build the £263m project.
The proposed Barking Riverside extension would add 4km to the London Overground Gospel Oak to Barking line, and take it from Barking to a new station at Barking Riverside.
Barking Riverside is the largest housing development in east London, with planning permission for up to 10,800 new homes. The developer, Barking Riverside Ltd, which is a joint venture between the Greater London Authority and London & Quadrant, is stumping up £172m of the cost. The remainder is being provided by TfL.
The planned rail link comprises construction of 1.6km of new railway and remodelling existing tracks which form part of Network Rail’s Essex Thameside (Tilbury Loop) line. The new section would start at a junction with that line and be built partly on a viaduct passing below the bridge at Renwick Road before rising and turning south to pass over existing Network Rail tracks and Choat Road to access a new elevated terminus station at Barking Riverside.
A Transport & Works Order was submitted in March 2016. Construction is scheduled to begin in late 2017, with services running in 2021.