Stoney Creek Bridge

In 1893, 3,000 carloads of rock were railed from a Salmon Arm quarry. During construction, a carpenter struck by dislodged rock sustained fatal injuries on falling to the bottom of the ravine.[4] A Hamilton Bridge Co. employee fell to his death later that year.[5] This company replaced the existing crossing with an 82-metre (270 ft) high, 148-metre (486 ft) long structure, incorporating a 102-metre (336 ft) steel arch span.[6] After load testing, work was suspended until the spring 1894 completion and opening.[1][7] The design could comfortably support the combined weight of two mountain region locomotives.[6]

To handle heavier locomotives, CP proposed to replace the structure with a new 95-metre (311 ft) cantilever deck truss with 34-metre (111 ft) flanking anchor spans, built adjacent to the existing bridge. However, the unsuitable rock foundation of the canyon made the idea uneconomical. Instead, truss arches, positioned outside of the existing ones, would widen each side by 1.5 metres (5 ft).[6]

In 1929, the Canadian Bridge Co. undertook the installation, and replaced the deck lattice girder spans with deck plate girders.[8] The design could support four locomotives with a combined weight of 1,100 tons. In 1970, the load capacity was re-evaluated for the introduction of bulk commodity unit trains. In 1999, another strength evaluation was conducted.[6] The western approach comprises a sharp bend in the track to cross the gorge at its narrowest point.[8] This track curvature places considerably greater centrifugal forces on the west end of the structure, which limits current train speeds to 40 kilometres per hour (25 mph).[6]

Since the opening of the lower Macdonald Track in 1988 for westbound traffic, the Stoney Creek arch on the Connaught Track has primarily handled the lighter eastbound trains. Although fatigue damage during the prior 15 years was considerable, the bridge maintains an expected long life. However, to safely sustain present and future train loads, some deficient parts may require strengthening.[6]

In 2015, six cars of a westbound freight derailed on the bridge. The train had diverted to the eastbound route because the Mount Macdonald Tunnel was being vented. The incident occurred when the train lost momentum on the steeper grade and stopped with the cars on the bridge. However, restarting on the curve caused the heavier cars at the front and rear of the train to lift the lighter middle cars from the track.[9]

               1894 steel bridge, c.1894,                 ┼              1885 wooden bridge, c.1890

When opened, the 1894 bridge ranked seventh in height:
Garabit Viaduct (1885) 124 metres (407 ft)
Loa Viaduct (1888) 102 metres (336 ft)[10]
Pecos River High Bridge (1892) 98 metres (321 ft)[11]
Malleco Viaduct (1890) 96 metres (315 ft)[12]
Kinzua Viaduct (1882) 92 metres (301 ft)[13]
Young's High Bridge (1889) 86 metres (283 ft)
Stoney Creek Bridge (1894) 82 metres (270 ft)

Although no longer world rating, the crossing ranks second to Lethbridge Viaduct (1909) 96 metres (314 ft) in Western Canada.

The bridge and its locale have been the subject of numerous CP promotional photographs that have gained iconic status. Among the most recognized are those by CP special photographer Nicholas Morant featuring The Canadian when it was the railway's flagship streamliner.[14] In the mid-1980s, several television commercials to promote the railway were filmed at the bridge site.[8]