North Downs Line

The North Downs Line is the name of the passenger train service connecting Reading, on the Great Western Main Line, to Gatwick Airport, on the Brighton Main Line. It is also the name used to refer to the line over which these services run between Reading and Redhill, which was authorised by Acts of Parliament in 1846 and 1847 and constructed by the Reading, Guildford and Reigate Railway (RG&RR), opening in 1849. The stated objective of the company was to "secure through traffic passing between the West, North and Midlands and the Channel Ports avoiding the congestion of London and thus saving time, distance and expense."

The line runs roughly parallel to the North Downs escarpment between Ash and Redhill. The South Eastern Railway which operated the line from its opening, ran passenger services on the line from Reading to London Charing Cross via Redhill and even today, the distances along the line are measured from the terminus of the former SER.

Technical information
The line is two track throughout, except for a short single track section on the approach to Reading. Reversible working is provided on the down line between Guildford and Shalford. The entire line is designated W6 gauge and overnight engineering possessions of up to 4.5 hours are available. The major capacity constraints are the platform capacities of Reading, Redhill and Gatwick Airport stations.
 * Reading to Wokingham is electrified (3rd rail, 750 V DC) and signalled under the TCB (Track circuit block) system from Wokingham Signal Box. Signalling headways are 3 minutes for fast services and 3.5 minutes for stopping services. The line speed is 70 mph, except for two 30 mph restrictions (on the approach to Reading and through Wokingham station).
 * Wokingham to North Camp is also under the control of Wokingham Signal Box, however long distances between signals increase headways to 6 minutes and 11 minutes for fast and stopping services respectively (the longest headways on the line). This section is not electrified and the line speed is 70 mph.
 * North Camp to Shalford Junction is controlled from Guildford (TCB). Signalling headways are 2 minutes with an additional 1 minute added for stopping services. This section is electrified (3rd rail, 750 V DC) from Aldershot South Junction. The line speed is 70 mph, except for a 40 mph restriction at Ash Junction (between Ash and Wanborough) where the line curves sharply, and a 30 mph restriction on the approaches to Guildford station.
 * Shalford Junction to Reigate The route leaves the Portsmouth Direct Line at Shalford Junction and there is a 20 mph restriction. From here to Reigate the line is not electrified and is controlled by Guildford from Shalford Junction to Gomshall and by Reigate Signal Box (TCB) from Gomshall to Redhill. Signalling headways are 5 minutes for fast trains and 7 minutes for stopping services. The line speed varies from 30 mph (on the approach to Shalford junction) to 70 mph.
 * Redhill to Reigate is electrified (3rd rail, 750 V DC). The approach to Redhill is controlled by Three Bridges Signalling Centre and has a 30 mph speed restriction.

At Reading, North Downs Line services normally terminate at platforms 4a and 4b on the south side of the station, although access to other platforms is possible via a junction with the Great Western Main Line (see map, right). Trains could formerly access the north side of Reading station via an underpass, although this has been disused for some time. The access to platforms 4a and 4b is via a short single track section, which severely limits capacity. As part of the 2012 Reading resignalling scheme, an additional platform will be provided for North Downs Line services. The underpass may also be reinstated.

Network SouthEast originally planned to electrify the whole route, with a completion date of 1993 being published, but these plans were dropped.

Current passenger services and rolling stock


The main services on the line are provided by First Great Western using Class 165 and Class 166 Network Turbo diesel multiple units. Hourly semi-fast services run from Reading to Gatwick Airport and there is an hourly stopping service between Reading and Redhill. At Redhill the Gatwick Airport services reverse to head south along the Brighton Main Line. Before 1994, the stopping services continued to Tonbridge, however the line between Redhill and Tonbridge was electrified in 1993 to provide an additional diversionary route for Eurostar trains to continental Europe. Services on this line now run to London Bridge and are operated by Southern.

Additional services on the North Downs Line are provided by South West Trains between Reading and Wokingham (trains to/from London Waterloo) and between Ash and Guildford (trains to/from Alton or Ascot). Southern operate weekday peak hour services between Reigate and Redhill and onwards to London.

Passenger services and rolling stock before privatisation


Steam traction was replaced by 3R (Class 206) DEMUs on 4 January 1965. The new trains consisted of two 6S (class 201) coaches from the Hastings Line coupled to adapted 2EPB driving trailer units. As a result of the visible difference in width between the narrow Hastings Line stock and the standard width Hampshire trailer, the units were nicknamed Tadpoles. Additional peak time services were hauled by class 33 diesel locomotives until May 1977.

The express service from Reading to Gatwick Airport was launched on 12 May 1980 using three-car class 119 DMMUs, based on the Western region. The trains were especially modified for this service to create extra luggage space: the buffet counter in the centre coach was removed. Class 101 three-car units were later used on the route as well.

All of the stations between Shalford and Betchworth inclusive, were recommended for closure in the Beeching Report of 1962. The report recommended that the whole of the North Downs Line should be developed as a trunk route.

Freight services and rolling stock
there are no scheduled freight services which use the line. The Travelling Post Office train from Dover to Manchester via Tonbridge, Redhill, Guildford and Reading was routed along the line from May 1988 until 2004. The Network Rail 2008 Strategic Business Plan recommended that an enhancement project for the line should be pursued to enable freight traffic from the Channel Tunnel to use the line.

Electrification proposals
An article in the August 1981 issue of Modern Railways magazine studied an electrification strategy for the then Southern Region of British Railways. Among the then-unelectrified routes covered were the sections of the North Downs Line between Wokingham railway station and Ash railway station (Aldershot South Junction) and Shalford Junction and Reigate. The plans for electrification were initially shelved prior to World War II, over concerns that little traffic would be generated. However, the article saw potential on the route with the area rapidly developing since that time, and also with the foresight of the Channel Tunnel traffic, as well as the ability for cross-country passenger and freight workings to be diverted along the route. Of course, some of the routes included were indeed later electrified in the time after the article was published; other routes mentioned including South Croydon-Oxted-East Grinstead* (1987), Bournemouth-Poole/Poole-Weymouth (1988), Hilsea/Farlington Junction-St Denys/Eastleigh (1990) and Redhill-Tonbridge (at the time still the furthest extant of North Downs Line services, in 1994).

According to internet sources, the considerations to electrify these sections of the North Downs Line arose again as part of the Blackwater Valley Rail Survey, dated 1991. Motive power from the outset would have been the BR Mark 1-based electric stock classes, but proceeding with the idea to electrify the line was halted when the conventional diesel multiple units on the region begun to be replaced by the current Class 165/166 'Turbos'.

''*Hurst Green/Tunbridge Wells to Eridge and Uckfield was also mentioned in the same scheme, but still remains unelectrified today. The Tunbridge Wells-Eridge portion closed to BR passenger traffic in 1985.''

Lineside features


On the south side of the line between Chilworth and Gomshall a yew hedge known as Jesse's Seat has been cut into the shape of a pheasant. It is a memorial to a guard who was killed in an accident at this spot in about 1910.

Network Rail routes
The service uses all or part of the following Network Rail routes:
 * SW 210 from Reading
 * SW 265 from Wokingham
 * SW 110 from Guildford
 * SW 300 from Shalford Junction
 * SO 560 from Gomshall to Redhill

Typical off-peak journey times from Reading


Based on the December 2006 - May 2007 timetable. Stations in italics are served in peak hours only.

Between Guildford and Redhill the off-peak stopping service pattern alternates every hour, giving Shalford an hourly service and Chilworth, Gomshall, Dorking West and Betchworth one train every two hours.

During peak hours the stopping service between Guildford and Redhill calls at all stations.