p118  Chapter 6
Locating the Central Pacific Railroad

On account of the magnitude of the undertaking of building the Pacific Railroad, both because of the length of •nearly 1,800 miles and the remote and difficult country it traversed, certain principles which governed its location may be mentioned. In the case of railroad terminals as widely separated as Sacramento and Omaha, the shortest distance between the two is measured on the trace of a great circle. This trace cannot be drawn as a straight line upon an ordinary map, which is meant to represent the surface of a sphere on a flat surface. For short distances, the variation would be of no great importance, but over a spread of 1,800 miles there would be a wide difference between the shortest distance as measured on an ordinary map and as measured on a great circle. The topography of the country will rarely, if ever, permit a railroad to follow a great circle trace exactly, but it is remarkable how closely the located lines of the Pacific Railroad adhered to the trace of a great circle drawn  p119 between Sacramento and Omaha. The greatest divergence, •some 110 miles, was found at the north end of Great Salt Lake and at the big bend of the Humboldt River.

On the line as built, seven topographical divisions of the country were traversed that were of major importance in fixing the route of the railroad. From west to east, these divisions were as follows:

The great mass of the southern Rocky Mountains also had an important bearing upon the location of the railroad. These mountains were regarded by the locating engineers of that time as practically impassable, from both financial and physical points of view. These factors determined that the location of the railroad should be across the Wyoming Basin, thus passing around the northern end of the southern Rocky Mountains.

Topographic Features

Sacramento, from which city the Central Pacific Railroad was built, lies on the alluvial plain of the Valley of California. The city is located on high ground about the river, at an elevation of  p120 twenty feet or more above sea level. The river, which is affected by the tides, furnishes a route for transportation by boat to San Francisco, •about 130 miles to the west.

The plains extend eastward from Sacramento to merge without break with the Sierra Nevada. The rising ground of the mountains becomes apparent at a distance of •fifteen to eighteen miles from the city. Along the line of the railroad there is a fairly uniform rise in •103 miles to the •7,018‑foot summit of the Sierra. In the vicinity of Donner Pass, the mountains on the south rise to elevations of •10,000 feet, while to the north the elevations are somewhat less.

The Sierra Nevada is a tilted fault block, the central mass of which is granite. There is a long uniform slope on the western side, where rivers have incised deep canyons. On the eastern front there is a steep escarpment, with a drop of •2,500 to 3,000 feet from the high passes to the floor of the valleys that border the foot of the mountains.

The fact that there were two ranges of about equal height in the mountain chain to be crossed was important in fixing the railroad location. North of the headwaters of the South Fork of the American River, the mountains divide into two ranges, between which lies Lake Tahoe and the surrounding level lands. At the lake, the east and west distance between the two ranges is about •twenty miles. The Truckee River drains Lake Tahoe and much of the surrounding watershed. This river runs northward from the lake, and then pursuing a generally eastward and northward direction for •some fifty miles, reaches Big Bend, where it makes a sharp turn to the left and flows northwestward into Pyramid and Winnemucca lakes.

This favorable situation was recognized by Judah when investigating the route for the Central Pacific Railroad. He also expressed himself in favor of a route up the valley of the Humboldt River to reach Salt Lake City, a route that had been used for years by emigrants and was generally well known. It terminated at Humboldt Wells, from which point there was a choice  p121 of routes across the intervening mountains to Great Salt Lake, and then around the lake, either to the north or to the south.

Locations

By the time Theodore Judah was ready to present the plan for a Pacific Railroad to investors, the main outlet had been determined. The road was to be built from Sacramento, California, to a point on the Missouri River, preferably Omaha. It was to cross the Great Plains, the Wyoming Basin, pass Great Salt Lake, cross Nevada, and go over the Sierra Nevada. Judah visualized the road as far east as Great Salt Lake and the road was built along the route he outlined.

Judah's final decision to cross the Sierra Nevada by the route that the railroad followed was not reached until after he had considered a number of other routes, each of which had its advocates. The investigations were made at various times from 1860 on, and were summarized in Judah's report of June 1, 1863.

Five routes were examined. The first was from Folsom, at the terminus of the Sacramento Valley Railroad, up the ridge via Georgetown to the summit of the mountains at the headwaters of the Middle Fork of the American River. This route was rejected because of the heavy grades required — •150 feet to the mile. The second route was the one upon which the railroad was built. The third route led by way of Nevada City and the ridge between the North and Middle forks of the Yuba River. It was known as the Henness Pass road. This route involved crossing deep mountain canyons on the western slope of the mountains and a bad location to reach the Truckee River on the eastern side. For these reasons it was rejected. The fourth route crossed the canyons of the South and Middle forks of the Yuba River and continued up the North Fork of that river via Downieville and the Yuba Pass, and through Sierra Valley to the Truckee River. The fifth route led via Oroville, and up the Middle Fork of the Feather River, crossing the highest mountains  p122 at Beckwourth Pass. This route had the advantage of lighter grades and crossed the mountains by a lower pass, but it involved such heavy and costly construction that it was rejected. Years afterward, in 1903, the modern Western Pacific Railroad was built over practically the same route, excepting that it followed the North Fork of the Feather River. It was a costly line because between Sacramento and Winnemucca, common points on the two lines, the Western Pacific is •sixty-five miles longer than the route of the Central Pacific. It was also true that to have built on this fifth route would have meant abandoning the lucrative traffic of the Comstock mines. The fifth route was therefore rejected by Judah, and his decision was sound.

After making his investigation, Judah decided that the railroad should be built directly across the Sierra Nevada by way of a ridge that lay between the Bear and South Yuba rivers on the north, and the North Fork of the American River on the south. He had made reconnaissance of the route in company with Dr. Strong of Dutch Flat in 1860, just as he had made a preliminary survey across the mountains to a junction with the Truckee River in 1861. The results of his work were embodied in a report to the president and directors of the Central Pacific Railroad, dated at Sacramento, October 1, 1861. Some excerpts from the report will explain his conclusions. Speaking of the survey he said:

 p123  Referring to the problem of reaching an elevation of 7,000 feet in the distance from base to summit, Judah said:

Judah set forth the general characteristics of the Sierra Nevada and described the ridge up which the railroad was located:

The most important controlling gaps were Clipper Gap, •forty-two miles from Sacramento; New England Gap, •six miles farther on; Long Ravine, •about four miles from Illinoistown (Colfax); and Emigrant Gap, •eighty-two miles from Sacramento. Beyond the last gap the line was on the side of a mountain and the gaps no longer controlled the surveys. The most  p124 characteristic portion of the ridge as described by Judah lies between Colfax and Emigrant Gap, an air-line distance of •about twenty-one miles. In this section the distance between the Bear River and the North Fork of the American River is about four miles, the rivers running parallel and more or less southwest. The ridge between the two streams may average •from one to two miles in width and is the remnant of an ancient peneplain. The ridge is cut by numerous small canyons, tributaries of the main streams. In following up the ridge it was necessary to pass around these gullies so that the distance of the railroad between the points mentioned would be •about twenty-nine miles. This twisting of the location increased the length of the line by approximately •eight miles.

The North Fork of the American River runs in a canyon much deeper than that of the Bear. At Cape Horn the depth from the railroad to the river is •about 1,500 feet. Above Towle station, the railroad runs on the edge of the canyon, where the drop to the river is •some 2,000 feet, while on the opposite side the Bear River runs •1,000 feet below. At Emigrant Gap, where the ridge narrows to a knife edge, Bear Valley is •nearly 600 feet below the track, while several miles away the North Fork of the American is •more than 2,500 feet below the railroad. These data give some idea of the favorable location selected by Montague for the railroad after Judah's death.

In the surveys directed by Judah, it was his opinion that the line could reach the South Yuba River bottom from Bear Valley on Bear River and follow it generally to Summit Valley and across that valley to the summit. However, it was determined later to keep to the side of the mountain above the Yuba bottoms and the line reaches the river only at Summit Valley, elevation •6,800 feet. Above the eastern end of Summit Valley, where the summit was reached, a tunnel •1,659 feet long was excavated through the culminating ridge, •124 feet below the summit. The highest point reached was an elevation of •7,042 feet in the tunnel.

 p125  After crossing the summit of the Sierra Nevada, Judah's problem was to drop down to the Truckee River. He describes the situation in the following words:

The line was continued down from the summit along the mountainside above Donner Lake with maximum grades of 105 feet per mile. In order to reach the Truckee River as quickly as possible, advantage was taken of two ravines, the largest being the ravine of Coldstream Creek. Truckee River was reached after •eleven and one half miles of maximum grades, the direct east and west distance being •about eight miles.

The first surveys demonstrated that a line could be found up the ridge to the summit and thence to the Truckee River with maximum grades of •105 feet per mile. In discussing the merits of this location, Judah mentioned some important and favorable elements of the line:

Judah also investigated the possibility of a line leading southward through the Truckee Meadows and Washoe and Eagle valleys to the Carson River, and by way of that stream to the open plains near Humboldt Lake. He rightly concluded that such a line was feasible but much longer than the one down the Truckee.

The reports by Judah give details of the location of the line up the Sierra Nevada, based upon his preliminary survey. Later location surveys varied from the original location at a number of places, but the line as built followed his first selection of the ridge between the Yuba and Bear rivers on the north and the North Fork of the American River. The route down the Truckee to the Big Bend at Wadsworth was also followed and it remains today the line of the Southern Pacific eastward from California.

On one point only was Judah incorrect. He believed that the snow could be handled in winter by snow plows, but experience during construction showed that this was impossible and that snow sheds were an absolute necessity in order to keep traffic moving.

Judah did not live to complete the location surveys eastward from the Truckee River, but he had urged the necessity of continuing them to Salt Lake City. In his cost estimates, he added to his own those of Lieutenant Beckwith as far as Salt Lake City and also those of the other government estimates to Council Bluffs. The total was $99,870,000. He pointed out important considerations that gave the route up the Humboldt manifest  p127 advantages over any other route for a railroad line. It was left to Montague and his corps of assistants to finish the line to a junction with the Union Pacific at Promontory.

The final location on which the road was built was made by Judah as far east as Dutch Flat, •sixty-six miles east of Sacramento. His preliminary location beyond led into Bear Valley on Bear River, and thence up the canyon of the Yuba River. When Montague took charge, he made a more detailed study of the mountains and became convinced that a better line would be found by continuing along the mountainside well above the Yuba River instead of in the canyon near the stream. Had Judah lived, it is certain that he would have ordered additional surveys of this particular location and it is likely that he would have reached the same decision as did Montague. During 1864 and into 1865, further detailed studies of the location were undertaken, with the result that Montague submitted his findings to the management and advocated his location as having better grades and easier construction. Naturally, there was some question of adopting the new line rather than that made by Judah. To settle the matter, Stanford employed George E. Gray, who came out from the New York Central Railroad and examined the situation. Gray reported on Montague's location in the following terms:

Gray also commented on the general excellence of the location up the mountains and assured the management of the railroad that the line as laid out could be built. Gray's decision settled the matter, and Montague's location was adopted. It was decidedly the best possible route.

The work of locating the line up the Sierra Nevada engaged the engineers up to the end of 1865. In his first report, dated October 8, 1864, Montague stated that an experimental survey line had been run late in 1863 to the Big Bend of the Truckee from the terminus of the Judah surveys. The result was "highly satisfactory, developing a line with easy grades and curves, and for the greater portion of the distance with very light work." Montague states that "from the Big Bend, the choice of routes must be hereafter determined by proper exploration and surveys."

In 1866, active work was undertaken to determine the route through Nevada and Utah to a possible junction with the Union Pacific. In his report of February 8, 1867, Montague says that the line had been finally located beyond the eastern boundary of California to a point •thirty-four miles into Nevada toward the Big Bend of the Truckee River. Lines of exploration across central Nevada and through Utah were made by several parties under Mr. Ives, Mr. Eppler, and Mr. Buck. Two lines south of Great Salt Lake, together with the same number north of the lake, were investigated as far as the mouth of Weber River at the foot of the Wasatch Mountains near Ogden. The records show that a total of •3,623 miles of line were examined, either as a reconnaissance or by preliminary surveys. No portion of the central part of Nevada was omitted from the examination,  p129 and the same was true of the region of Utah westward from the Wasatch Mountains. The instrumental surveys extended from the Big Bend of the Truckee, "via Say's Station, Truckee Desert, Desert Gate, Sink Humboldt, north side of Humboldt Lake, and thence following the valley of Humboldt River to Humboldt Wells."

The result was that the original idea of a location up the Humboldt was confirmed. A glance at the map would seem to indicate that a direct line across Nevada south of Great Salt Lake to Salt Lake City might be the best. It was, in fact, the route of the overland stages. However, the physical obstacles were too great. The isolated mountain ranges scattered in that region would have made necessary a zig-zag line to round the ends of the ranges that lead through narrow passes. In addition, a uniform grade could not be obtained because the mountains, with desert valley between, gave an up-and‑down profile that made such a location impossible. A line might have been run from Humboldt Wells south of Great Salt Lake, but lack of water along the route, the necessity of crossing •twenty miles of Great Salt Lake Desert, which might again be flooded by the waters of the lake, and the •twenty-five miles additional distance to the mouth of Weber Canyon determined the selection of the northern route. Montague's report summarizes the conclusions from the 1866 surveys and investigations:

During 1867 the explorations were continued for a line to the north of Great Salt Lake at the same time that location surveys were being extended into Nevada and additional preliminary lines were being run. One of these preliminary lines extended from Wells across the eastern border of Nevada to the Salt Lake Valley. Another was carried from the mouth of Weber Canyon across the ranges to a tributary of the Green River at Granger. Trial lines were also run upon the valley of Utah's Bear River, by way of the river and also across the mountains from Bear Lake to Cache Valley on Little Bear River. The country through the eastern mountains by way of Weber and Echo canyons, Chalk and Sulphur creeks, and along the northern base of the Uinta Mountains was explored by trial lines that extended to the tributaries of Green River. Together with running reconnaissance lines, the company explored the country from the western base of the Wasatch Mountains to Green River over a north and south distance of •150 miles.

The transit party starting at Humboldt Wells and ending at Salt Lake City covered •950 miles, while the exploring party traveled •1,403 miles. In addition, large-scale triangulation nets were made from the Big Bend of the Truckee River to the Reese River in Nevada.

It was quite evident from the wide extent of the surveys of 1866, 1867, and 1868 that the Central Pacific intended to build across the mountains into Wyoming as far east as the Green River. In fact, President Stanford stated later that they had hoped to meet the Union Pacific at a point as far east as Cheyenne.

By the end of 1867, the •twenty miles of final location across  p131 Nevada had been finished and in the first six months of 1868 it had been completed for •248 miles eastward of the Big Bend of the Truckee. In addition, final location east of Humboldt Wells had been completed to Independence, while locating parties were working on both sides of Promontory Point. When the roads were joined, after Central Pacific grading had been carried eastward to Bear River and Ogden, final location had been completed as far east as Ogden. Surveying expenses on reconnaissance, preliminary, and location surveys had risen progressively from the start. The amounts were: June 1, 1863, $33,889; March 1, 1864, $59,457; February 8, 1867, $181,121; June 30, 1868, $271,182.

It was the practice of the national government to have the railroad examined by special commissioners from time to time. One such commission composed of G. K. Warren, Brevet Major General, U. S. A., J. Blickensderfer, Jr., civil engineer, and James Barnes, civil engineer, made a report to O. H. Browning, Secretary of the Interior, on November 23, 1868, in which the following statement occurs:

The problem of location had been solved, but there were other details that required attention. The law granting a subsidy to the railroad had provided that grades as used on the Baltimore and Ohio Railroad should not be exceeded. These limits were grades of •116 feet per mile and curves as  p132 sharp as •400 feet radius. However, principles of economy in operation dictated that grades of the least possible rise be obtained and that curves of larger radius be used whenever possible. The location had been made with these limitations in mind.

The line from Sacramento to the summit of the Sierra Nevada was the most difficult, because it had to reach an elevation of •over 7,000 feet in •105 miles, of which •about fifteen miles was across the nearly level valley floor. Therefore, the line was located diagonally across the mountains in order to gain distance. From Sacramento to the summit, there were •11.2 miles of level track, •20.9 miles of •105 feet per mile grade, and •9.55 miles of maximum grade of •116 feet per mile. Lighter grades intervened, the average grade in •195 miles to the summit being •66.97 feet per mile.

Profile view of the Central Pacific Railroad

From the summit, for •11.5 miles the line descended to the Truckee River, with maximum grades of •ninety-five feet per mile. From that point for over seventy-two miles to the Big Bend of the Truckee, •189 miles from Sacramento, the line followed a descending grade along the river, the average grade being •35.12 feet per mile. Beyond the Big Bend of the Truckee River the average grades were all lighter, the heaviest, however, being •52.8 feet per mile. The Big Bend of the Truckee, where the town of Wadsworth was established, was at the western end  p133 of the Truckee and Humboldt Desert. For •forty miles the route led across the open desert to the west shore of Humboldt Lake. Skirting the low grassy shores of the lake, the line then followed up the valley of the Humboldt River for •291 miles to Humboldt Wells, •520 miles from Sacramento. The line was located away from the river in most places to avoid the bottom lands that were apt to be flooded. As far as Golconda, the river runs in the sediments of the former Lake Lahontan, a good region for a railroad to avoid. In this stretch of the line to Humboldt Wells there were several canyons and narrow gaps, as at the Palisades, but these offered few difficulties to the locating engineers.

At Humboldt Wells the valley of the river came practically to an end, so it was necessary to cross the intervening mountains toward Great Salt Lake. The location was not difficult, as the several basin ranges had wide gaps between them and there were also open valleys. The route was somewhat zigzag for this reason. •About nine miles east of Wells, the highest point, with an elevation of •6,166 feet, was reached in a pass through the Independence Range. From that point on, there was a gradual down grade for •sixty-two miles to Umbria Junction, near the present station of Lucin, where the Great Salt Lake Desert was reached. In that stretch of the line, such open valleys as Thousand Springs Valley were followed on through open passes in the Pequop, Toana, and Pilot ranges. The lowest point in the line into the desert was reached some twelve miles east of Umbria, where the elevation was about 4,340 feet. From there the line climbed the Ombe Mountains, a range of low hills about 375 feet high at the pass at Ombe, and then descended 500 feet to the flats at the upper end of Great Salt Lake. For •about twenty-five miles along the shore of Spring Bay, the line was practically level. Monument Point, at 4,220 feet, was rounded in this stretch of line, •142 miles from Wells and •662 miles from Sacramento. •About seven miles east of Monument Point the line commenced to climb the Promontory Mountains. The pass  p134 was through another open valley where the mountain breaks down from the north and then rises into the high range that extends southward into Great Salt Lake. The climb of •685 feet to Promontory Summit was made in •sixteen miles, and from there the line descended the eastern slope of the mountains to the flats across Bear River Valley. The Bear River was crossed •about ten miles north of Bear River Bay, the upper section of Great Salt Lake. Turning southward and eastward, the line followed the plains at the base of the Wasatch Mountains until it finally reached the mouth of Weber Canyon, •752 miles from Sacramento.

The valley on Promontory was where the line met the rails of the Union Pacific, but the Central Pacific line was graded into Ogden. The location of the two lines over the Promontory Mountains was practically the same, and, as both were graded, the observer can still see the unused grade, sometimes within •100 feet of where the rails were later laid.

Some statistics are available. In a distance of •450 miles from Sacramento, the location was based on •264 miles of tangent or straight lines and •186 miles of curved lines, of which the curves of minimum radius •(573 feet) made up less than 1 per cent of the total length. East of Wells, for •219 miles the grades were •less than 25 feet per mile for •133 miles; •from 25 to 50 feet for •35 miles; and •50 to 75 feet for •50 miles. These results were obtained only after careful surveys had been made.

The railroad was built along the line as located, and with one major exception is still there today. The exception is the Lucin Cutoff crossing Great Salt Lake. That was finished in 1903, a third of a century after the completion of the road over the Promontory Mountains. The plan of building directly across the lake was indeed considered by the early engineers, but rejected on account of cost, lack of information regarding the lake bottom, and uncertainty as to the lake levels. Some records then available indicated a rising lake in the years from 1850 to 1868. To this day traces of ancient Lake Bonneville are  p135 in evidence that show that prehistoric water levels were •at least 1,000 feet above the modern lake. To have crossed the lake where the modern line was built would have saved •forty-five miles of distance and a climb of •680 feet over the Promontory Mountains, but it was just not possible in 1869. There is no question that the early engineers found and used the best route there was from Sacramento to Ogden, and their work remains today as evidence of great ability and far-seeing vision.

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