There were originally 7 tunnels measuring over 2,152 feet (656 m) in the Kicking Horse River Valley between the Kicking Horse Pass and the Columbia River. One of these, the Corry Brother’s Tunnel, was named after the company that constructed it. During construction it also became known as “Mud Tunnel”. It was only 470 feet (143 m) in length but was constructed through an unstable spur where the river flows in a sharp bend. It curved at nine degrees through a variety of difficult material. The spur had gravel on the top, and then a thick stratum of extremely tenacious blue clay, and beneath that lay a bed of boulders which required blasting.
Morley Roberts, who worked on the tunnel, recalled that only those on the top level did not have the threat of anything falling on them.
“I never felt safe, for every minute or so would come the cry, ‘Look out below!’ or ‘Stand from under!’ and a heavy stone would come thundering down the slope right at us. I had been working three days, and on the third day a rock about a foot through, weighing perhaps 80 lb., came over without anyone crying out until very late. It came down and seemed about to drop right where I stood, so I made a prodigious jump on the instant... and struck my right knee under the cap on the end of the wheelbarrow handle just as the stone buried itself in the ground where I had been standing.”
Morley Roberts, 1887. The Western Avernus
(London: Smith, Elder and Co., 1887)
It took almost five months to construct as it collapsed twice during construction. Although timbered, the east end of the tunnel collapsed on July 23, 1883 bringing down 15,000 cubic yards (510 cubic metres) of material. Then again in October, when the track was about to be laid, a second slide occurred at the east end brought down 9,000 cubic yards ( 255 cubic metres) of material. It was lined with 780 board feet (238 m) of lumber for each line each foot of the passageway. Nevertheless in 1887, shortly after regular service began, it caved in again.
The railway was faced with relocating of the line. They had two choices. Build bridges and route the line to the other side of the river or build a sharp bend around the spur. They chose the latter creating a 22 15’ curve that with its 259-ft (79 m) radius was one of the sharpest on a railway main line on the continent. Cars had to be uncoupled and joined together with short chains to be pulled around the spur. Although intended as a temporary expedient, the curve remained in use until 1906 when a 700-foot (213 m) tunnel replaced it.
The Spiral Tunnels and the Big Hill on the Canadian Pacific Railway. 2009. Graeme Pole, Mountain Vision Publishing.
Tracks, Tunnels and Trestles: An Environmental History of the Construction of the Canadian Pacific Railway. 2007. Heather Anne Longworth B.A., Acadia University Master of Arts thesis.
Van Horne’s Road. 1974. Omer Lavallée, Railfare Enterprises Ltd.
West of the Great Divide. 1987. Robert D. Turner, SONO NIS PRESS.