Mount Macdonald Tunnel

The Mount Macdonald Tunnel is in southeastern British Columbia, on the Revelstoke–Donald segment. This single-track 14.66-kilometre (9.11 mi) tunnel, which carries the Canadian Pacific Railway (CP) main line under Mount Macdonald in the Selkirk Mountains, handles most westbound traffic, whereas the Connaught Tunnel handles mostly eastbound.

Mt. Macdonald Tunnel
Overview
LineCP
LocationRogers Pass.
Coordinates51°17′35″N 117°29′58″W
StatusActive
CrossesSelkirk Mountains,
below Rogers Pass
Operation
Opened1988
TrafficRailway
CharacterFreight service
Technical
Length9.11 miles (14.66 km)
No. of tracksSingle
Track gauge4 ft 8 1⁄2 in (1,435 mm) standard gauge
Mt. Macdonald Tunnel
Location in British Columbia

Shortcomings of the Connaught Track

By the 1970s, it was evident that the Connaught Tunnel alone could not meet the increasing traffic demands. The major growth opportunities were primarily in the bulk commodities of coal, sulfur, and potash.[1] In 1980, the estimated construction cost of $300 million was almost 20 per cent of CP's gross income for 1979. Furthermore, westbound grain transportation had been an ongoing liability for the railways. Consequently, CP was unwilling to proceed with a new tunnel unless the Crow Rate, which did not cover the variable cost of grain movement, was addressed.[2] In response, the federal government gradually increased this rate from 1983, before abandoning rate regulation in 1993.

The need for pusher locomotives was another encumbrance. During the pusher station's existence, six engineers, six maintenance workers, and nine locomotives, were based at Rogers. Five-engine units were used on heavy trains carrying grain, coal, and potash. Four-engine units were used on other freights.[3] A significant grade improvement would eliminate the need for pushers.

Proposals

To enable the reintroduction of double tracks, three schemes required a 1.8-metre (6 ft) lowering of the Connaught Tunnel floor, complemented by a new approach to serve the east portal:

  • south side of the Beaver Valley with a loop up to the portal.
  • higher than the existing track, requiring higher bridges over the five major streams, before levelling to the portal.
  • below the existing track from Rogers with 1.0 grade to Stoney Creek, followed by two 1.6-kilometre (1 mi) long spiral tunnels up to the portal.

However, lowering the floor would be extremely difficult while maintaining traffic flow.[4]

Three schemes offered a straight new tunnel at a lower elevation:

  • approximating the 14.6-kilometre (9.1 mi) tunnel as built.
  • a 15.8-kilometre (9.8 mi) tunnel from about the chosen west portal to about the Mount Shaughnessy Tunnel south portal.
  • a 12.4-kilometre (7.7 mi) tunnel from about 250 metres (820 ft) west of Loop Creek to about the chosen east portal.[5]

Mike Wakely, Regional Engineer, Special Projects, suggested the selected option, which provided a 1.0 grade from Rogers, and a west portal 4.8 kilometres (3.0 mi) west of Glacier station. The budget, including approaches, was $600 million.[4] In 1975, preparatory work began in earnest.[6]

Macdonald Track

The 34.8-kilometre (21.6 mi) route of surface track and tunnels, within a 30-metre (100 ft) wide right-of-way, uses continuous welded rail.[7]

Macdonald Tunnel route
MileLocationMileLocationMileLocation
68.3Frainea74.5Gully bridge78.6Connaught Creek bridgei
68.6Cupola Creek bridgeb75.0Surprise Creek culvert79.3Bear Creekj
69.4Alder Creek culvertc75.0Wakelye79.4Mt. Macdonald Tunnel (E. portal)
71.3Mountain Creek bridged76.5Stoney Creek bridgef84.9Macdonaldk
73.7Cedar Creek culvert77.1John Fox viaductg88.5Mt. Macdonald Tunnel (W. portal)
74.2Raspberry Creek culvert78.0Mount Shaughnessy Tunnelh89.9Ross Peak

^a . Connaught Track and Macdonald Track diverge;[7] named for former Pacific Region V.P.;[8] previously called Rogers.[9]
^b . Length: 40-metre (130 ft); two span; double track;[7] Cana Construction[10] completed in July 1984.[8]
^c . Connaught Track had to be moved 9.1 metres (30 ft) into the mountainside along this section to accommodate the new lower track.[7]
^d . Length: 96-metre (315 ft); 2 X 250-ton spans. Height: about 44 metres (145 ft) below Mountain Creek bridge on Connaught Track.[11] Cana Construction[10] completed in fall 1985.[12]
^e . A 2,700-metre (8,800 ft) siding;[13] named after Mike Wakely, a former chief construction engineer, who oversaw the years of preparatory work, but retired before the work was properly underway, and died soon after, never to see the completed project.[8]
^f . Length: 210 metres (700 ft); seven spans. Height: about 150 metres (500 ft) below Stoney Creek bridge on Connaught Track.[7]
^g . Length: 1,229 metres (4,032 ft); Pitts Engineering Construction began work in 1985;[14] 45 X 27.18-metre (89 ft 2 in) steel spans, each weighing 82 tonnes; brought from Calgary via the Crowsnest Pass, because too wide for the Spiral Tunnels,[12] and unloaded at the south end of the new Stoney Creek bridge;[14] supported on 44 custom-designed piers and two abutments; pier heights range from 4.6 metres (15 ft) to 21 metres (70 ft); cut and fill not adopted because it would undermine Connaught Track above, and encroach on highway below;[15] spans installed from early 1987 to that July;[14] walkway on north side;[16] named after John Fox.[7]
^h . Length 1.83 kilometres (1.14 mi).[17]
^i . Length 48 metres (156 ft); single span;[18] comprises a pair of 70-ton deck plate girders, offloaded near the east portal of the Connaught Tunnel, and hauled up to the highway and down to the site;[12] Cana Construction built.[10]
^j . A railway point.[13]
^k . A railway point.[13]

Construction
West portal (construction phase)

CP Rail built a substation in Revelstoke and from it constructed a 35kV operating distribution line along the railway right-of-way; originally built using both 69kV insulators and construction standards.[19]

On August 27, 1984, the Selkirk Construction joint venture (comprising S.A. Healey, Foundation Company of Canada, and Atlas Construction) began blasting from the east portal.[20] By mid-October, sufficient room existed to install their 6.7-metre (22 ft) diameter, 18-metre (60 ft) long, tunnel-boring machine (TBM). In December 1985, the tunnel passed 110 metres (360 ft) below the Connaught one, almost directly beneath the mountain peak.[21][22] On completion, Selkirk Construction had advanced 8.45 kilometres (5.25 mi) westward.

On October 5, 1984, the Manning-Kumagai (MK) joint venture (comprising Manning Construction and Kumagai Gumi) began from the west portal. Using the drilling and blasting method, 30 men, rostered in 3 shifts, completed 5.8 kilometres (3.6 mi) eastward. Meanwhile, the highway was temporarily relocated[20] to construct a 270-metre (880 ft) long reinforced concrete box in a cut-and-cover trench. This structure carries both the highway and protects the portal from avalanches.[23][24] In 1985, the words "Mount Macdonald Tunnel 1988" were stamped into the concrete cladding above the portal.[25] The eastern work camp was near the Mt. Shaughnessy Tunnel, and the western one at Flat Creek. A third camp for summer surface workers existed near Rogers.[23]

Work train (construction phase)

Breaking through on October 24, 1986, the approaching tunnels joined. Cementation Canada sank the 8.5-metre (28 ft) diameter, 350-metre (1,150 ft) deep, ventilation shaft. MK drilled and blasted the gate chamber below, and air tunnels to, this shaft. After concrete lining, the tunnel height is 7.9 metres (25 ft 10 in), and the width is 5.2 metres (17 ft) on the straights, and 5.5 metres (18 ft) on the curves. In September 1988, the final track concrete was poured.[20] The Paved Concrete Track (PaCT) rests on a 2.4-metre (7 ft 10.5 in) wide, 22.9-centimetre (9 in) thick, reinforced concrete slab.[17] The height clearance can accommodate any future electrification.[20]

A fleet of 50 dump cars were built exclusively for the project. About 5,000 tons of material were removed daily from the western side. Parks Canada allowed some dumping about 4.5 kilometres (2.8 mi) from the portal, creating a bed for track twinning. The remainder was dumped outside the park boundary at various proposed double tracking sites between Golden and Revelstoke. The 505 cubic metres (660 cu yd) of rubble produced daily at the eastern end was dumped into a large depression to create the grade.[26] Minus the 48-metre (156 ft) bridge, this fill covered the 1,337-metre (4,386 ft) distance to the Mt. Shaughnessy Tunnel.[18]

Tunnel ventilation

The purpose of the ventilation system is to prevent locomotives overheating and remove air pollutants. The opening and closing of the gates at the portals and mid-point assists the extraction process.[27] The mid-tunnel gate structure stands inside a 25-metre (82 ft) long, 27-metre (88 ft) high, and 16-metre (52 ft) wide, cavern. In a power failure, counterweights return all gates to the up position. Each gate has a central wooden panel designed to break if struck by a train. Although monitored at the Revelstoke control centre, the ventilation system is computer controlled, and adjusts to the type and size of train.[28] Standing at the top of the shaft, near the Rogers Pass highway summit, the ventilation building houses two fans, a standby 3,800 hp diesel generator, and two elevators. Used by maintenance staff, each open cage takes 11½ minutes to slowly descend an open elevator shaft to tunnel level.[29] A straight tunnel would have made the shaft location clearly visible from the summit monument. To hide the complex, a slight kink was made in the tunnel alignment.[23]

Operation

On November 9, 1988, the first official train travelled the Macdonald Track westward. About 535 metres (1,755 ft) west of the west portal, R.S Allison, CP president, connected the last track clip.[30] On December 12, 1988, the first revenue train, hauling coal, passed through the tunnel, and saved an hour on the journey.[7] The official opening of the $422 million tunnel was in May 1989.[31] The crest at the west portal is 90 metres (295 ft) lower than the Connaught crest.[11] The 0.7 gradient westward[32] eliminated the need for pusher locomotives. Nowadays, locomotives can climb the grade at 32 kilometres per hour (20 mph).[27] Loaded coal trains travel at 14 to 21 kilometres per hour (9 to 13 mph) through the tunnel. To ensure frequency vibrations do not cause damage to the track structure, the speed limit for all traffic is 48 kilometres per hour (30 mph).[33]

Maintenance

CP repairs 15 to 61 metres (50 to 200 ft) of PaCT each year. Drain holes cored down to a longitudinal collector drain under the tunnel reduce failures from excessive surface water. Slab cracking, owing to insufficient lateral and longitudinal reinforcing in the PaCT slab, can be repaired with epoxy resin in minor cases. Injecting the resin restores structural integrity. Slab removal and replacement is needed in serious cases. Since 1993, a total of 115 metres (378 ft) of PaCT have been replaced in the two tunnels.[33]

The hardware for power, communications, and signaling is obsolete. The slow ventilation systems can take 45 minutes to purge the air after each train. Consultants are advising on possible improvements, but it will probably take 5 to 10 years to modernize the tunnel.[34]

Notability

Twelfth longest railway tunnel when opened:
Seikan Tunnel (1988) (Japan) 53.85 km (33.46 mi)
Daishimizu Tunnel (1982) (Japan) 22.20 km (13.79 mi)
Simplon Tunnel (1906) (Switzerland) 19.80 km (12.30 mi)
Shin Kanmon Tunnel (1975) (Japan) 18.71 km (11.63 mi)
Apennine Base Tunnel (1934) (Italy) 18.51 km (11.50 mi)
Rokkō Tunnel (1972) 16.25 km (10.10 mi)
Furka Base Tunnel (1982) (Japan) 15.44 km (9.59 mi)
Haruna (1982) 15.35 km (9.54 mi)
Monte Santomarco Tunnel (1987) (Italy) 15.04 km (9.35 mi)
Gotthard Tunnel (1882) (Switzerland) 15.00 km (9.32 mi)
Nakayama (1982) 14.86 km (9.23 mi)
Mount Macdonald Tunnel (1988) 14.66 km (9.11 mi)

However, it took the title from the Cascade Tunnel (1929) 12.6 km (7.8 mi) as the longest railway tunnel in the North America. The project was the largest CP expansion of capacity since the building of the transcontinental in the early 1880’s.[31] In 2016, the tunnel was inducted into the North America Railway Hall of Fame.[35] Tunnel 4 of the Cuajone–El Sargento line in Peru is of similar length, and which is the longer of the two is disputed.

Accidents

2005: While clearing ice in the tunnel, an employee died when struck by a falling 225-kilogram (496 lb) chunk.[36]

2019: An avalanche descending upon a stopped train at Wakely derailed seven container-carrying flatcars.[37]


Footnotes
  1. Backler 1981, p. 403.
  2. Backler 1981, p. 405.
  3. "Prince George Citizen, 12 Jun 1980". www.pgnewspapers.pgpl.ca. p. 37.
  4. Booth 1991, p. 45.
  5. Backler 1981, p. 304.
  6. "Red Deer Advocate, 24 Nov 1982". www.newspapers.com. p. 41. ….CP Rail has been doing preparatory work for the tunnel since 1975. The engineering and assessment work is complete. All that remains is a new Crow Rate to begin construction.
  7. Steed 1993, p. 20.
  8. Booth 1991, p. 25B.
  9. "Vancouver Sun, 4 Aug 1984". www.newspapers.com. p. 47. The new surface route begins on the East at Rogers siding where, at present…."pusher locomotives"….added to westbound trains to push them up the steep 2.2 per cent grade to Stoney Creek. It then parallels the existing track at a lower elevation, along the valley wall….
  10. "Calgary Herald, 7 Jun 1984". www.newspapers.com. p. 34. Cana Construction….begun….construction of three railway bridges….Cupola Creek….Mountain Creek….Connaught Creek.
  11. Steed 1993, p. 21.
  12. Booth 1991, p. 50.
  13. "2003 timetable" (PDF). www.mapleleaftracks.com. pp. 13–14.
  14. Booth 1991, p. 25C.
  15. Steed 1993, pp. 23–24.
  16. Steed 1993, p. 23.
  17. Steed 1993, p. 25.
  18. Steed 1993, p. 26.
  19. "Province, 12 Dec 1984". www.newspapers.com. p. 24. CP Rail has opened a hydroelectric substation and 83 kilometres of transmission lines to….the….Rogers Pass work project….BC Hydro's Revelstoke Dam will eventually be used to operate ventilation systems and lighting in three tunnels.
  20. Steed 1993, p. 32.
  21. Booth 1991, p. 46.
  22. Steed 1993, p. 15.
  23. Booth 1991, p. 47.
  24. Steed 1993, p. 31.
  25. "Calgary Herald, 23 Jun 1985". www.newspapers.com. p. 28.
  26. Booth 1991, p. 49.
  27. Steed 1993, p. 27.
  28. Steed 1993, p. 28.
  29. Steed 1993, pp. 16–17.
  30. "Branchline, January 1989" (PDF). www.bytownrailwaysociety.ca. p. 11.
  31. "Deseret News, 5 May 1989". www.deseret.com.
  32. Steed 1993, p. 30.
  33. Bilow, David N.; Paradise, Scott J. "Inspection, Maintenance, and Repair of PaCT Canadian Pacific Rogers Pass Tunnels British Columbia, Canada" (PDF). www.arema.org.
  34. "Railway Age, 17 Jan 2019". www.railwayage.com.
  35. "Mt. Macdonald Tunnel". www.casostation.ca.
  36. "Edmonton Journal, 24 Oct 2008". www.pressreader.com.
  37. "BC Local News, 26 Dec 2019". www.bclocalnews.com.

References
  • Booth, Jan (1991). Canadian Pacific in the Selkirks: 100 Years in Rogers Pass, second edition. BRMNA, Calgary, Alberta. ISBN 0-919487-15-7.CS1 maint: ref=harv (link)
  • Steed, Roger G. (1993). Canadian Pacific in the Selkirks (Volume Two). BRMNA, Calgary, Alberta. ISBN 0-919487-44-0.CS1 maint: ref=harv (link)
  • Backler, Gary G. (1981). "The C.P.R.'s capacity and investment strategy in Rogers Pass, B.C., 1882–1916". www.open.library.ubc.ca.CS1 maint: ref=harv (link)
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