Routes of the ECML, Selby diversion is northern half of the 1983 route (Black)
|Operating speed||200 km/h (120 mph)|
As of 2014 the line is used primarily by long-distance north-south services, as well as some freight trains.
From the northern end, the line runs off a junction with the southwesterly former York and North Midland Railway mainline from York south to Church Fenton and Brotherton; the line turns south, crossing the River Derwent. At the Leeds and Selby Line the line travels under the east-west railway, with junctions allowing trains from York to continue east to Selby, and trains from the south to continue west to Leeds. (see Hambleton junction) The line then runs southeast to a junction with the former York and Doncaster branch (Selby to Doncaster section), joining the line at a junction near to the village of Temple Hirst, just south of its crossing of the river Aire.
The line forms part of the East Coast Main Line (ECML), and part of section Network Rail's SRS G.07 track section (Colton junction-Doncaster) as line number LN600. The line is electrified at 25kV AC, route availability is 10, loading gauge is W9, running speed is mostly 125 miles per hour (201 km/h). The line is signalled under Track Circuit Block regulations.
As of 2014 the line has approximately 4 north-south long distance trains per hour.
In the 1970s the National Coal Board (NCB) began development of new underground mining complex, in the area around Selby, North Yorkshire, the Selby Coalfield; because of the risks to trains from mining subsidence a diversionary route for the ECML was built, paid for by the NCB. After opening in 1983 ECML trains no longer called or passed through Selby, instead leaving the former ECML at Templehirst junction and connecting with the former York and North Midland Railway line to York at Colton junction near Church Fenton. The NCB made the proposal in 1974, and following a planning enquiry in 1975 received consent in 1976.
Evidence at the planning enquiry showed that the mine would (in the local geological context of a high water table, and sand substrata) lead to unpredictable subsidence on the line from Selby to York (ECML)—and as such would render the line unsafe for a high speed service. The enquiry recommended that the line be re-sited.
Proceedings for an act to enable a new line began in 1977.[n 1] At the parliamentary reading of the bill it was claimed that the alternative of leaving a mile wide bed of coal unmined underneath the line would represent a loss of £500–800 million. The act was passed in 1979, the British Railways (Selby) Act, 1979.[n 2] Due to the long timescale of the planning process, the full design and construction phase was required to be carried out in four years  (by 1983[n 3]).
The line's design was for an operation speed of 200 kilometres per hour (120 mph), initially opening at 100 kilometres per hour (62 mph) with the line speed to be progressively raised. The railway line used standard concrete sleepers at 650 millimetres (26 in) spacing with rails of weight 54 kg/m. The junction at Colton used a fixed nosed crossings at an angle of 1.77° The line included chords allowing running from the Leeds-Selby Line. The estimated project cost was £60 million of which £48.4 million was for civil engineering.
Construction was formally started in July 1980, in the presence of Glynn England (CEGB), Peter Parker (BR), and Derek Ezra (NCB). The work was finished 3 months ahead of schedule, at a final cost of £63 million.  Diesel Multiple Units running from Hull to York began using the line in 16 May 1983, InterCity train services began running on the line from 3 October.
The line was the first purpose built section of high-speed railway in the UK having a design speed of 125 miles per hour (201 km/h). The new line also avoided the speed reduction over the swing bridge at Selby. The former ECML route, the NER's 1871 York and Doncaster branch was closed from Selby northwards.[n 4]
- See "British Railways (Selby)", London Gazette (47400), 6 December 1977: 15261 and Times (1 December 1977, p. 24)
- British Railways (Selby) Act (Elizabeth 11. 1979 Cap.x); An Act to empower the British Railways Board to construct works and to acquire lands in the district of Selby in the County of North Yorkshire; to confer further powers on the Board; and for other purposes
- The progress of the drift mine was scheduled to reach the land under the railway towards the end of 1983.
- Hoole (1986) states that the line south of Selby was single track, possibly incorrectly.
- Ordnance Survey 1:25000 2006; also Historic sheets 190, 205, 220, 221, 236
- "London North Eastern", Route Specifications, 2011, SRS G.07 – Doncaster – Colton Junction, pp.33–36
- "London North Eastern", Route Specifications, 2014, SRS G.07 – Doncaster (exclusive)- Colton Junction, pp.27–30
- Simmons & Biddle 1997, p. 137, 498.
- Hoole 1986, p. 229.
- Davis et al. 1985, p. 435.
- Davies, Fenwick & Bastin 1983, p. 719.
- Hansard HC 9 March 1978, §1758–9.
- Hansard HC 27 November 1978, §116.
- Collingwood & Fenwick 1985, p. 49.
- Collingwood et al. 1986, §143–146, pp.549–550.
- Bairstow 1995, p. 57.
- Collingwood et al. 1986, §97, p.538.
- Parkin, Michael (30 July 1980), "£60M Selby line starts", The Guardian: 2
- Collingwood et al. 1986, §108, pp.539–540.
- Hoole 1986, pp. 37–38, 229.
- "Parliamentary Notices – British Railways (Selby)", The Times (60175), 1 December 1977
- "BRITISH RAILWAYS (SELBY) BILL", Hansard – House of Commons 945, 9 March 1978, cc1755–91
- "BRITISH RAILWAYS (SELBY) BILL (By Order)", Hansard – House of Commons 959, 27 November 1978, cc107–32
- "BRITISH RAILWAYS (SELBY) BILL", Hansard = House of Commons 397, 13 December 1978, cc556–60
- Simmons, Jack; Biddle, Gordon (1997), The Oxford companion to British railway history from 1603 to the 1990s, Oxford University Press
- Davies, P. B.; Fenwick, T. H.; Bastin, R. D. (1983). "Selby Diversion of the East Coast Main Line. 1. The Background and Study of Alternatives. 2. Route Design. 3. Bridges". ICE Proceedings 74 (4): 719. doi:10.1680/iicep.1983.1361.
- Collingwood, R.W.; Fenwick, T.H. (1985), "Selby diversion of the East Coast Main Line: Construction", ICE Proceedings 78 (1): 49–84, doi:10.1680/iicep.1985.1019
- Davis, P.B.; Fenwick, T.M.; Bastin, R.D.; Rapley, D.G.; Kohler, J.H.; Cunningham, W.P.; Steven, T.C.; Taylor, M.J.; Bonnett, C.F.; Craine, G.S.; Elsworth, D.E.; Holmes, G.C.; Dolan, J.; Lewis, W.M. (1985), "Selby Diversion of the East Coast Main Line", ICE Proceedings (discussion) 78 (2): 435 –447, doi:10.1680/iicep.1985.1012
- Collingwood, R.W.; Fenwick, T.H.; Payne, P.G.; Jebb, G.J.C.; Berryman, A.W.; Couchman, M.; Fleming, W.G.K.; Thorburn, S.; Hughes, F.H.; Humphries, E.F.; Lewis, W.M.; Coper, G.H.; Spindel, J.E. (1986), "Selby diversion of the East Coast Main Line: Construction", ICE Proceedings (discussion) 80 (2): 537 –552, doi:10.1680/iicep.1986.746
|Wikimedia Commons has media related to Selby Diversion.|