Although from a "Diversionary" perspective, the Durham Coast line also fulfills the same purpose as the Leamside line over a longer section of the ECML, just with a slightly higher journey time cost.
The only non-diversion-able section of the northern ECML is Colton Jn-Northallerton, mitigated to some extent by this section being predominantly 4 track anyway.
But the Durham Coast line is electrified at 1500 volts for the Metro and thus cannot be electrified throughout at 25KV whereas the Leamside had existing electrified junctions at either end. It is also pretty much saturated with Metro trains. The only downside to the Leamside was the tight clearances on the Victoria Bridge which led to Washington - Penshaw North being singled in 1982. The Leamside also has considerable traffic potential in its own right (Newcastle - Washington - Penshaw - Fencehouses - possible Durham Parkway at Belmont - Ferryhill - Darlington (and Middlesbrough via reopened Sedgefield line) whereas the Durham Coast already has passenger services.
Last edited: