SCRCA Note: Temporary notes relating to Bridge 72 (Blea Moor Tunnel)

Submitted by mark.harvey / Sat, 17/11/2012 - 16:52
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The following information has been drawn from a range of sources and is included here as a temporary measure while the database is being constructed and populated.

  • Length 2629 yards (2404m). South portal at 249m25½c; north portal at 250m68c.; centre at 250m05½c. [A Network Rail sign at the north entrance states that the tunnel runs from 249m25c to 250m65c and that length is 1 mile 880 yards: this would make the tunnel 2640 yards long, but it is an error. Earlier and later signs beside the south portal gave the length as 2629 yards.]
     
  • Constructed 1870 – 1875 [source: Toothill & Armstrong (2009)]; completed 1875 (5). “1874” date stones on masonry above south and north portals. Max. depth 390ft/119m. During construction, five shafts were dug and used for ventilation, drainage, each providing two extra headings for tunnelling as well as access for the workforce and materials and the removal of spoil. Shafts, numbered from the south, were: Shaft A 249m44c depth approx. 76ft Shaft 1 249m62½c depth 217ft (227ft?) Shaft 2 249m75½c depth 385ft Shaft 3 250m37½c depth 390ft (380-400ft are figures sometimes given) Shaft B 250m57c depth approx. 91ft
     
  • Shafts A and B were temporary shafts, being filled in after use, although Shaft A has collapsed in recent years and has been fenced off by Network Rail. Traces of the Shaft B and its small spoil tip were obliterated when the area above the tunnel at the north end was afforested in the ?1970s The 10-ft diameter middle three shafts were left as permanent ventilation shafts and are visible today.
     
  • Several navvy settlements arose on Blea Moor above or adjacent to the tunnel and access across the moor for men and materials was provided by a tramway and inclined planes at either end. The remains of stationary winding engines are to be seen at 250m19½c (west) and 250m24c (east) of the tramway. Associated with these features is a complex of buildings and a tramway leading eastwards up to the gritstone quarry on the Crag of Blea Moor.
     
  • The permanent way inside the tunnel enters from the south at a gradient of 1 in 100 as far as 249m42c, after which it levels off before falling at 249.47c on a gradient of 1 in 440.
     
  • For the best and most authentic accounts of the building of this important structure, see the list of items given in appendix 10 of Musset, N: "The Settle – Carlisle Railway Resources Handbook".