Crows Nest Pass Line Location and Construction
By J.L. Davidson for Railway and Shipping World, May 1899.
The construction of the Crows Nest Pass line was notable from an engineering standpoint for at least two features, the celerity of construction and the skill shown in overcoming serious obstacles. To build a road through the Rocky Mountains, with a maximum grade of 1%, seemed nearly impossible. Yet the grade was not exceeded, and the railway is the best that crosses the Rocky Mountains.
Location of the Crows Nest Pass Line
The location survey for the Crows Nest Pass line was started in April, 1897, at Lethbridge, Alberta. Since preliminary lines had been run in 189293, the general route to be followed was already known. Starting from Lethbridge, the line ran to Fort Macleod, then to Pincher Creek, following the middle fork of the Old Man River to the summit of the Rocky Mountains, down Michel Creek to Elk River, then to Kootenay River, to Cranbrook and to Moyie Lake, along Moyie Lake, down Moyie River to Goat River Summit, down Goat River to Kootenay Flats, round the west side of Kootenay Lake to the Narrows, and down the Narrows to Nelson. In all, the route was a distance of 290 miles.
Location was carried on from five or six different bases; westward from Lethbridge, starting in April; westward from Elk River to Kootenay River, starting in May; westward from Wardner to Moyie Lake in May; down Moyie River from the foot of Moyie Lake to Goat River Summit, starting in July; from the summit westward to Kootenay Flats in November and from Kootenay Flats round the lake to Nelson in April, 1898. All the location proper was finished in March, 1898, although a good deal of re-location went on during construction.
Building the Trestle Bridge across the St. Marys River
From Lethbridge it was approximately a 1/2 mile to St. Marys River, where there was approximately 3 miles of trestle-work. A fly-line was run down along the side hill to the flats, so that the steam pile-drivers work below, as well as above. Three tracks were run along the course of the road, one outside of the trestle-work and two inside. The steam pile-driver, driving the outside sloping piles, came first, followed by another steam pile-driver driving the upright piles. The first pile-driver was on two flat cars, one on each track, and was shifted from side to side as the piles were driven. With the upright piles the driving was done at the rear end of the cars, as the piles were driven in between the tracks. Material was brought along on the track outside; a steam timber derrick putting it in place for the pile-driver. Pile-drivers were at work up above from the east end of the bridge. In this way the trestle was constructed in remarkably quick time. Temporary work was constructed under the span by means of decks; the decks that were brought along were already made up. One deck was laid on top of another until the necessary height was reached; the span was then placed in position, and the temporary work taken away.
Building the Line
The line crossed the valley, swung around a 10º curve on the trestle, and follows along the coulees. Very heavy cuts were encountered; after the slopes were taken out, one was 120,000 cubic yards. A trestle, 900 ft. long, was next, with a 200 ft. span. Heavy cuts again intervene, and Six Mile Coulee bridge was reached. Piles were driven to a height of 40 ft., and then decks of 15 ft. were strung across on the temporary work, and pulled up into position. A cable was stretched across the coulee, block and pulley were attached to the cable, and the bents placed in position one by one. It was impossible to locate around the hogs backs that jutted out from the side hill, so that it was necessary to have trestles and heavy cuts.
Eight Mile Coulee trestle was next reached; this was 600 ft. long and 110 ft. high. The piles were driven to a height of 50 ft. There was a 15-ft. deck and bents up to grade here. After passing through a very heavy cut, a trestle 900 ft. long on a 3º curve was constructed in the same manner as the one over the St. Mary River. Heavy cuts and fills with a few small trestles were encountered till Sixteen Mile Coulee trestle was reached. This was 800 ft. long and 133 ft. high, with 200 ft. span. The temporary work consisted of 3 decks for the span, 35 ft. each, the bents being 15 ft. apart.
Across the Prairie to the Rockies
The line reached the rolling prairie, and no difficulty was encountered to Fort Macleod at 37 miles. The road then followed the Old Man River, and crossed Pincher Creek, 22 miles distant, with a trestle 1,200 ft. long and 122 ft. high, with a span 250 ft. long. It then followed the south side of Old Man River, with a rising grade, till the south fork of Old Man River was crossed. This bridge was 840 ft. long, and 135 ft. high, with 2 spans of 150 ft. each, piles 30 ft. and decks of 15 ft. bents. The temporary work for spans used 15 ft. bents 15 ft. apart for 70 ft. in height, with a 30 ft. deck to span. The road then wound in and out along the south bank of the Old Man River, and the foothills of the Rockies were reached. Heavy rock cuts were encountered there. A trestle was erected on a 4º curve over a dam, but the whole side hill, 1,200 ft. across, started to move toward the river. The trestle had to be abandoned and a lower grade taken. Fill was made instead of trestling. It was necessary to keep ballasting this, as the grade kept sinking. The cause of this, from all appearances, was that there was loose material embedded in the hollow, the sides and bottom of which were solid rock.
Through the Pass
The entrance of the Crowsnest Pass was made at 92 miles. In the mountain division trestling and culverts were of great importance, as they were used in great numbers. The trestles consisted of single deck trestles up to 40 ft.; on soft material piles were used and on hard ground mud sills were used. The standard trestles ran up to 110 ft., with diagonal bracing on all over two decks. The culverts employed were box, pile and open. Box culverts were used the most in mountainous country. Where necessary, a culvert was put in unless the water could be drained along the side of the dump. If there was a small stream, a culvert usually 3 ft. x 3 ft. was built. Box culverts varied in size from 2 ft. to 4 ft. in width and from 2 ft. to 5 ft. in height. Sometimes it was necessary to put in a double box culvert; these were generally 4 ft. x 4 ft. Some culverts used on the road were over 100 ft. long. Open culverts were generally pile culverts, and were from 6 ft. to 14 ft. in width. Mud sills were used on hard ground. Open culverts were used up to a height of 5 ft. for spans of 12 ft. to 14 ft. Eight stringers were used.
Reaching the Summit
The line followed and crossed the Old Man River with a single span. In three places the course of the river was changed, as a much better location was to be had by this change. There was a steady rise in the grade, and heavy cuts and fills were needed. Crows Nest Lake was reached at 100 miles from Lethbridge. Very heavy rock cuts were encountered along the lake, with grade going up. The divide or summit of the Rockies was reached at a distance of 105 miles, which was passed at an elevation of 4,434 ft. Summit Lake was next reached, only a few hundred feet from Crows Nest Lake, but the latter drains to the east by the Old Man River, and Summit Lake drains to the westward by Michel Creek.
By the contract with the Government 100 miles were to be finished by January 1st, 1898. They were finished Dec. 13, 1897. Because there were no waggon roads west of Crows Nest Lake, it was necessary for the Company to build one. They started it in July, 1897, from Crows Nest Lake, and from Kuskanook in September. The work crews met on Moyie Lake in November. Over 200 miles of waggon road were built in four months. When the location was nearly completed to Kootenay Flats, contractors were put in along the line from Crows Nest Lake to Kuskanook by January 1, 1898. Storehouses were built on an average of 25 miles apart in the mountain divisions. Supplies were rushed in from MacLeod and from Nelson to Kuskanook, and in the centre from Jennings, Montana, by Kootenay River to Wardner. Mail service was established along the line, and by February between 6,000 and 7,000 men were employed on the line.