Brighton main line


The Brighton Main Line is a :Category:Railway lines in the United Kingdom|British railway line divided in the north into two sections running from London Victoria and London Bridge to Brighton. It is about 51 miles long, and is electrified throughout. Nearly all passenger trains are provided by Govia Thameslink Railway which operates the Southern, Gatwick Express and Thameslink brands. A small section has Great Western Railway services, currently sole operator of the line from Gatwick Airport to Reading, Berkshire known as the North Downs Line. The many Sussex services to Central London use the line and generally its branches as do south London, East Surrey and Tonbridge, Kent services.

History and geography of the line

Original proposals

There were six original proposals to build a railway between London and Brighton. The London and Brighton Railway emerged with an Act of Parliament of 15 July 1837 after a prolonged and expensive battle, with the most direct route, from the London and Croydon Railway at Norwood Junction to Brighton, using the L&CR from Norwood to London Bridge. A condition required by Parliament was that the railway should share its line between Croydon and Redhill with the South Eastern Railway main line to Dover. This clause gave rise to 60 years of disputes between the two companies.

Brighton line

Land use between London and Brighton was largely rural. The line was planned to traverse the North Downs, the Wealden ridge and the South Downs while avoiding steep gradients.
Due to the difficult terrain and relatively sparse population between Croydon and Brighton, the line by-passed several towns and villages on the London-Brighton road, such as Reigate and Crawley. Even so, it required substantial earthworks, notably through the North Downs at Merstham, with one of the largest cuttings in Britain; seven tunnels ; and several embankments. To avoid steep gradients or detours, the, maximum Ouse Valley Viaduct was built near Balcombe.
The line opened in two stages:

Branch lines

The branch line from Brighton to Shoreham-by-Sea was finished on 12 May 1840, before the main line, as it did not involve significant civil engineering works. The Newhaven section did not materialise until 1846, when the Brighton - Hastings line was opened by the Brighton Lewes and Hastings Railway. A few weeks later the L&CR, the L&BR and other railways in Sussex amalgamated to form the London, Brighton and South Coast Railway.

Lines to Victoria

A branch line from Norwood to Crystal Palace was built in 1851, extending to Sydenham in 1854, Balham and Wandsworth in 1856, Battersea in 1858, and London Victoria in 1860. A cut-off line reducing the distance between East Croydon and Balham opened in 1862.

Quarry line

There were frequent disputes resulting from the companies' sharing of the busy section between East Croydon and Redhill. The LB&SCR owned the section between East Croydon and Coulsdon North, and the SER from Coulsdon South to Redhill. Eventually the LB&SCR built the "Quarry Line", a by-pass for express trains between Coulsdon North and Earlswood, avoiding Redhill. It opened on 8 November 1899.

Electrification

The line was the first UK main line to be electrified throughout. The LB&SCR electrified its South London Line on 1 December 1909 using an overhead high-tension single-phase system; within three years the line from Victoria to Selhurst railway station was also converted. In 1921 plans were drawn up to extend overhead electrification to Brighton,. In 1925 it was extended toward the edge of today's Greater London at Coulsdon North, before being scrapped by the amalgamated operator under the 1923 grouping: Southern Railway which decided to standardise on the third-rail system of the former London and South Western Railway. In 1928/29 the lines began conversion to third-rail operation.
The change to third rail electrification was in place southward to Coulsdon North by 1929 - to Three Bridges in the north of Sussex in July 1932, then reaching Brighton and West Worthing on the coast on 1 January 1933.
The third rail is electrified at 750 V DC, and in the early part of the 21st century had its power supply upgraded for the introduction of Electrostar stock by Southern. Traction current supply is supervised by Lewisham, Selhurst and Brighton electrical control rooms which will be superseded by the Three Bridges ROC.

Accidents

The line is four-track to Balcombe Tunnel junction, where it becomes double track as far as Preston Park. Except for a pair of platform loops at Haywards Heath, there are no passing loops.
The fastest trains from Brighton to Victoria stop only at Gatwick Airport; some trains also stop at Hassocks, Burgess Hill, Haywards Heath, Three Bridges, Horley, East Croydon and Clapham Junction. Thameslink services from Brighton via East Croydon continue to London Bridge, Blackfriars, City Thameslink, Farringdon, St Pancras, and stations in North London and Hertfordshire, to Luton and Bedford.
Non-stop Gatwick Express trains run between London Victoria and Gatwick Airport. A train departs in both directions every 15 minutes, with a journey time of 30 minutes.
Great Western Railway run trains between Gatwick Airport and Reading via Redhill and the North Downs Line.
A 24-hour service runs between Three Bridges and Bedford via London Blackfriars with a frequency of one train per hour route throughout the night.

Bi-directional signalling

Between Balcombe Tunnel Junction and, the line reduces from four tracks to two, with only a quadruple-tack passing loop at. A broken-down train in this section causes the most disruption; therefore, to minimise the effects, the line is divided into three sections of bi-directional signalling, which allows trains to cross over and run on the right-hand track. These are:
At the passing loop through Haywards Heath, the two outer tacks are likewise cleared for bi-directional use throughout. The two inner tracks are only signalled bi-directionally south of Haywards Heath station itself, allowing trains to reverse at the station to/from the south; north of the station these tracks can only be used in their respective directions.

Branching routes

Branches from the line to Victoria

Until 2012, at Battersea Park, the South London Line to London Bridge. This was replaced by Overground services from Clapham Junction to Dalston Junction.

Branches from the line to London Bridge