Dartford Loop Line

The Dartford Loop Line (often referred to as the Sidcup Line) is one of three lines linking London with Dartford in Kent, England. It lies to the south of the other two: the North Kent Line and the Bexleyheath Line.

History
In June 1862 the South Eastern Railway obtained powers for a second ten mile line between London and Dartford from a junction with the main line at Hither Green to the North Kent line at Dartford in order to reduce congestion on the North Kent line and to give a more direct route between London and Dartford. This was to be routed via the town of Sidcup.

The Dartford Loop Line opened on 1 September 1866. (A loop line in railway terminology is a line which leaves the main line and then rejoins it later on.) The line initially had only five new stations : Lee, Eltham (now Mottingham), Sidcup, Bexley and Crayford. The station at Hither Green, near Lewisham, where the line deviates from the main line, was built after the opening of the third North Kent route, the Bexleyheath Line in 1895.

Pope Street, now New Eltham station, opened in 1878 between Eltham and Sidcup stations. Hither Green finally opened in 1895 serving both the Dartford Loop Line and the main line via Tonbridge. The final station to open was Albany Park in 1935. The Loop Line originally passed through mainly open country and farm land but it stimulated development around the new stations.

In 1899 the Lee Spur, a single track link between the up line of the Dartford Loop Line and the Hither Green marshalling yard, was built. The spur is occasionally used by freight and engineering works trains.

The Loop Line was electrified by the Southern Railway in 1926 along with the two other lines to Dartford.

In 1942 a double-track loop (the ‘Dartford Loop’) came into use between the North Kent and Dartford Loop Lines, creating a triangular junction. This allowed direct running between the two routes, avoiding the need for a reversing manoeuvre at Dartford.

In 1955 the platforms on all Loop Line stations were extended to accommodate ten carriage trains, although many peak services continued to be operated by eight carriage trains. Most stations had goods yards which closed during the 1960s and became car parks.

In the late 1960s the Dartford Loop Line along with the two other North Kent routes were re-signalled which saw the replacement of semaphores with colour light signals. In November 1970 most of the mechanical signal boxes on the line closed. In the mid-late 2000s the Dartford Area Resignalling Scheme saw the line resignalled.

Infrastructure
The line is double track throughout and electrified at 750 DC third rail.

Stations
The line is a little over 14 km in length. The following are the stations served:
 * Hither Green - the station lies on the main line from London to Kent: there are separate platforms for the Loop Line
 * here there is a triangular junction - the Lee Spur - for freight traffic going to the extensive Hither Green freight sidings
 * Lee - opened in 1866
 * Mottingham - opened in 1866 as Eltham, renamed Eltham & Mottingham in 1892 and then Mottingham in 1927
 * New Eltham - opened in 1878 as Pope Street renamed New Eltham in 1886
 * Sidcup - opened in 1866
 * Albany Park - opened 7 July 1935 to serve a new housing development
 * Bexley (the scene of the Bexley derailment)
 * Crayford
 * here there is a triangular junction with the North Kent Line providing access to the Slade Green carriage sidings and to Dartford.

Future plans
The line was due to be served by Thameslink trains following the completion of the first phase of the Thameslink Programme, however plans have since seen these services added to the North Kent Line instead.

Service patterns
Train services are operated by Southeastern (train operating company). All services run to London Charing Cross or London Cannon Street.

Off-peak & Saturday:


 * 2tph between London Charing Cross & Gravesend (not calling at Lewisham, St Johns & New Cross)
 * 2tph between London Cannon Street & Crayford, continuing to London Cannon Street via North Kent Line & Greenwich Line (calling at Lewisham, New Cross & St Johns)

Evenings & Sunday:


 * 2tph between London Charing Cross & Gravesend (calling at New Cross on Monday - Saturday evenings only, not calling at St Johns & New Cross on Sunday's)

The London bound peak service is :


 * 3tph to Charing Cross starting from Sidcup and running fast from Hither Green to London Bridge
 * 3tph from Gravesend or Gillingham to Charing Cross running fast from New Eltham to London Bridge
 * 3tph from Dartford or Crayford to Cannon Street stopping at all stops

The Sidcup Line has always been a fairly busy freight route for trains to Kent. Most services use the Lewisham flyover via Nunhead.

Rolling stock
Rolling stock used on the line is Class 465 and Class 466 'Networkers' and Class 376 Suburban Electrostars.

Accidents
On 11 October 1977 the derailed wagons of an eastbound coal train were struck by a Northfleet to Dunstable cement train between Lee and Mottingham. The locomotive ended up at the bottom of a garden of a house in Mottingham. There were no serious human injuries but several caged budgerigars in the garden were killed.

On 4 February 1997 an EWS fright train derailed near Bexley station (the Bexley derailment).