The earliest section of the line operated between Devonshire
Street railway station (Mile End) and Romford from 1839 and was built by the
Eastern Counties Railway (ECR). The London terminus was then moved to
Bishopsgate railway station (initially known as Shoreditch) on 1 July 1840 and
the line was extended out to Brentwood in the same year. A further 51 miles of
route was added to link London with Colchester by 1843.[3] The original gauge
for the line was 5 feet, but this was converted to standard gauge (4′8½″) in
1844.
The section of line between Colchester and Ipswich was built
by the Eastern Union Railway to standard gauge and opened for passenger traffic
on 15 June 1846 and the route to Norwich (Norwich Victoria railway station)
opened in 1849.
Eastern Counties Railway and Eastern Union Railways and
others were amalgamated to form the Great Eastern Railway in 1862.
The London terminus was again moved, this time to Liverpool
Street on 2 February 1872.
The line was ‘grouped’ into the London and North Eastern
Railway in 1923 and from 1948 formed part of the Eastern Region of British
Railways.
In the 1930s a flyover was constructed just west of Ilford
to switch the main and electric lines over, to enable main line trains to
utilise Liverpool St’s longer west side platforms without having to cross east
side suburban traffic in the station throat. The new arrangement also
facilitated cross-platform interchange with the Central line at Stratford,
services commencing in 1946. Either side of Ilford Flyover, there are
single-track connections between the slow and fast pairs of lines, with the
westbound track extending to Manor Park railway station and just beyond. A
short fifth platform face serves the track at Manor Park, but it sees no normal
use. The eastbound track extends as far as Ilford, connecting with that
station’s fifth (bay) platform, which does see limited passenger operations. It
was also envisaged that a flyover would be built at the country end of Gidea
Park Carriage Sidings to switch Southend Victoria trains from the mains to the
electrics, instead of at Shenfield London end junction as they do now.
Plans were drawn up in the 1930s to electrify the suburban
lines from Liverpool Street to Shenfield at 1500 V DC and work was started on implementing
this. However, the outbreak of the Second World War brought the project to a
temporary halt and it was not until 1949 that the scheme was completed with
electrification being extended to Chelmsford in 1956.
The British Railways 1955 Modernisation Plan called for
overhead line systems in Great Britain to be standardised at 25 kV AC. However,
due to low clearances under bridges the route was electrified at 6.25 kV AC.
The section between Liverpool Street and Southend Victoria was completed in November
1960. Extensive testing showed that smaller electrical clearances could be
tolerated for the 25 kV system than originally thought necessary. As a result
it was now possible to increase the voltage without having to either raise
bridges or lower the tracks along the route to obtain larger clearances. The
route between Liverpool Street and Southend Victoria was converted to 25 kV AC
between 1976 and 1980[5] Electrification was extended to Norwich by 1986.
In 1986 it became part of Network SouthEast. Between 5
January 1997 and 31 March 2004, suburban and medium distance services were
operated by First Great Eastern, while fast mainline services were operated by
Anglia Railways. All services are now operated by Greater Anglia.
Liverpool Street IECC replaced signal boxes at Bethnal Green
(closed 1997), Bow (closed 1996), Stratford (GE panel closed 1997), Ilford
(closed 1996), Romford (closed 1998), Gidea Park (closed 1998), Shenfield
(closed 1992) and Chelmsford (closed 1994). The system uses BR Mark 3 solid
state interlockings, predominantly four-aspect signals and a combination of
GEC-Alsthom HW2000 and Smiths clamp-lock point machines.
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