The scheme for this system was developed by Transport for London to meet the existing and anticipated demand for public transport in East London caused by the Thames Gateway redevelopment, and has been planned to allow for a possible future upgrade to tram operation.

EL2 operated over the whole length of the phase 1 route between Dagenham Dock and Ilford until March 2016, when it was amended to run to Becontree Heath after leaving Barking.

[10] In 2013 it was proposed to extend route EL1 from Thames View Estate to Barking Reach and a consultation was held.

[12] In 2020, the route EL1 was extended from the Barking Reach terminus to further serve the new housing developments that had been built in the area.

[16] Early proposals for extensions have included Gants Hill for the Central line, Rainham, Barkingside, Romford, Elm Park and Collier Row and Harold Wood.

[17] Additional proposals include services to Gallions Reach for the Docklands Light Railway, East Ham, Silvertown and Stratford.