Rio Grande Western's Bingham Low Grade Line

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Overview

Rio Grande Western's Bingham Low Grade Line was started in April 1906 and completed in February 1907. Known officially as the Bingham Branch Extension, the purpose of the line was to build a modern low-grade railroad line from the mouth of Bingham Canyon, at 4972 feet elevation, to the main assembly yard of Utah Copper Company deep in Bingham Canyon, at 6340 feet elevation. The new line was 11.93 miles in length, which resulted in a line that had a 2.5 percent grade, and was known for its three horseshoe curves needed to make the climb into the canyon. The new line replaced the severely overworked Copper Belt Railroad.

The expansion of Utah Copper to feed the new Magna mill, along with the likewise expansion of Boston Consolidated, would need a much better transportation system to get the very large quantities of low-grade copper from Utah Copper's Bingham mine, out of Bingham Canyon and 16 miles north to the new Magna mill. At the center of all this was the Rio Grande Western, and its Copper Belt connection at Bingham. With the Copper Belt being the only way to get Utah Copper ore out of the canyon, it was obvious that it would immediately be a serious bottle neck in the transportation process.

The construction of Rio Grande's Bingham Low Grade Line, which the local press called the "Bingham Sky Line," was in response to the need for higher capacity rail transportation in the booming Bingham Mining District. Both Utah Copper and Boston Consolidated were building mills outside of the district and both would soon be needing transportation facilities to move the projected vast quantities of low grade copper ore.

The Copper Belt railroad, then in use, was both too steep, with 7 percent grades, and was not constructed to allow movement of the tonnage needed to keep the two companies mills in operation.

Map

RGW Bingham Low Grade Line Map -- A section of the ICC valuation map that shows the Bingham Low Grade Line, with its many curces as it climbed into Bingham Canyon.

D&RGW Bingham Low Grade Line -- Map showing the abandoned route of the D&RGW Low Grade Line, superimposed on the 1952 USGS "Lark" topographic map.

Timeline

April 22, 1905
To alleviate traffic congestion in Bingham Canyon, as early as April 1905, Utah Copper had its own engineering crews surveying a new railroad route to move its copper ore from the mine, down to the mil it had completed in the lowest part of Bingham Canyon. The projected route for this particular, but early version, was a grade of 2-1/2 percent down to a point opposite the Yampa smelter. The line would descend to the bottom of the canyon by use of switchback tracks, about a mile in length, to the Utah Copper mill. This method would allow the use of standard locomotives and heavy trains. (Deseret News, April 22, 1905)

July 30, 1905
The Low Grade Line was surveyed starting in late July 1905. (Salt Lake Mining Review, July 30, 1905, p. 31)

January 2, 1906
The route surveyed by Utah Copper for its own rail line to haul ore from its mine to its newly completed mill brought speculation that Rio Grande Western would also build a rail line in Bingham Canyon, making a total of three railroad routes in the canyon, which were to include the existing Copper Belt in combination with RGW's existing Bingham Branch, a new line to be built by Utah Copper, and a new line to be built by Rio Grande Western. "The new railroads, which will in all probability be begun in the near further, will be on either side of the canyon. The road on the east side where Copper Belt's tracks lay, will be a considerable distance above the Belt and will not interfere with it in any way." "For some time past the Rio Grande officials have been trying to find a solution of the ore-moving problem. The rapid construction of the Utah Copper mill at Garfield, the capacity of which will be 11,000 tons of ore daily, has aggravated the situation and makes it necessary for Rio Grande to make haste. This large tonnage to be handled properly and profitably, necessitates more facilities, as the Copper Belt will be wholly inadequate to transport it." "Whether the east side of the mountain will be tunneled has not been decided upon, although rumor has it that a tunnel will be recommended." "With three roads hauling ore it is thought that the ever-increasing output will be handled in first-class shape." (Deseret News, January 2, 1906)

January 22, 1906
In an agreement dated January 22, 1906 between Rio Grande Western on one side and Utah Copper, Boston Consolidated, and American Smelting and Refining on the other side, the railroad agreed to provide for the movement of ores and concentrates between the mines at Bingham and the mills and smelter at Garfield.

March 2, 1906
Several D&RG officials from Denver arrived by private car to attend a special meeting of the Rio Grande Western stockholders. The special meeting was held in Salt Lake City to "vote on the proposed extensions of the line at Bingham. The changes were agreed on and work will start immediately at a point between Garfield Junction and Dalton, to extend through to form a connection with the Carr Fork branch of the Copper Belt system. Although the new branch will be short, a heavy grade will be encountered to make connection with the Copper Belt." (Salt Lake Herald-Republican, March 2, 1906)

April 1906
Utah Construction Company began the grading work in April 1906. (1909 Bingham Commercial Club Souvenir booklet)

June 9, 1906
"The sky line of the Copper Belt now being constructed on the west side of main town, high up on the mountain, is being rushed with all possible speed. The grading has now reached a point above Wall's mill and is being pushed as fast as men can be found to move the dirt." "The new road enters the canyon at Copperton and makes a gradual ascent upon 2 percent grade and its destined for the Utah Copper and Boston Consolidated ore bins. The rails of the new road will parallel the Copper Belt through town and will be almost directly over the present tracks, and the grade cut into the vertical side of the mountain." (Deseret News, June 9, 1906)

June 10, 1906
"The past week has been a hard one on the producers of Bingham. The four engines of the Copper Belt railroad have been out of service most of the time and all are now in the repair shops. Accidents to the Telluride power lines have also added to the worry and inconvenience of the mine and mill operators. For two days the Ohio Copper company's mill was out of commission because the Copper Belt line could not deliver ore and following that its power was entirely cut off through the accident to the Telluride company's power lines." "The Utah Copper and all the other mines which have to depend on the Copper Belt for delivery of ore have been registering kick after kick, but without avail, as the bad weather and crippled locomotives have made it impossible for the road to handle its trains properly. The mine bins of both Utah Copper and Ohio Copper companies are said to be full to the point of breaking and the companies are praying for a chance to get it moved and relive the strain." "The sky line of the Copper Belt road now being constructed on the west side of Bingham and high up on the mountain side, is being rushed with all possible speed. the graders have now reached a point above Colonel E. A. Wall's mill, with the objective points, the Utah Copper and Boston Consolidated ore bins, within easy striking distance. This new road enters the canyon at Copperton, and makes a gradual ascent upon a 2 percent grade. The rails of the new road will parallel the tracks of the present line through town and almost vertically above, where the grade has been hewn out of nearly vertical cliffs. Over this road will roll the thousands of tons of ore per day that will supply the big mills and smelters at Garfield. (Salt Lake Herald, June 10, 1906)

June 18, 1906
A preliminary survey for a 2400-foot track to run from the Utah Apex to the Yampa mine spur of the Copper Belt has been started during the past week by Rio Grande engineer H. C. Goodrich." "The steam shovel to be used by the Utah Copper is now on the ground. Workmen have been busy during the past few days in rigging up the machinery and within the next fortnight it will be in use." "The big tunnel of the Utah Copper is progressing as rapidly as can be expected and according to the report from the mine superintendent, everything is progressing satisfactorily." "A tunnel nearly 4000 feet long will be driven through the mountain for the new Sky Line of the Rio Grande running to the Boston Con. and Utah mines. The tunnel will start in the east side of the mountain just above the depot and will come out opposite the brick schoolhouse." (Deseret News, June 18, 1906, "Bingham Mining Notes")

June 26, 1906
Rio Grande Western filed suit for right-of-way against the Frederick L. Bemis and the Bingham Copper Hill Mining company. (Salt Lake Tribune, June 26, 1906) (The Bingham Copper Hill later became the Bingham-Butte, and later the Montana-Bingham.)

September 1906
The shovels of the construction company struck copper ore while excavating for the new line. (Salt Lake Mining Review, September 15, 1906, p. 39)

The construction of the new line included a new assembly yard called Cuprum, located high on the south slope of the canyon, about 200 feet above the Rio Grande Western's depot for the town of Bingham. The new Low Grade Line connected with the Copper Belt's line about a mile further up the canyon, at Copper Belt Junction, just up-canyon from the surface workings and ore bins of the Utah Copper Company. The grade of the new line was kept low by building south along the east slope of the Oquirrh Range, outside of Bingham Canyon, and gaining elevation by looping back north, using a spectacular horseshoe curve, thereby entering the canyon about 500 feet higher than the Bingham Branch at the same point. The abandoned roadbed of the loop is still visible in aerial photographs of the area today.

Rio Grande Western's new Low Grade Line was about 13 miles in length, between the lower end at Loline Junction and the upper end at Copper Belt Junction. This compared to less than six miles for the combined RGW Bingham Branch and (by this time) D&RG's Copper Belt Railroad that the new line replaced between the same two stations.

(The Low Grade Line was also called the Lo-Line, similar to the station called Loline Junction where the new line connected with the existing Bingham Branch. In the railroad's employee timetables, the new line was called the Bingham Branch Extension.)

January 27, 1907
"Tomorrow morning the Sky Line road of the Rio Grande company into Bingham will be opened to traffic between the mines and smelters of the valley and Garfield. " "From Garfield Junction on the flat below the mouth of the main Bingham canyon to the upper terminal, at the Utah Copper company's property, the distance by the road is a little more than seven miles; in a direct line it is not half that far. By making the circuitous climb, however, the grade is kept down to the maximum of a trifle over 2 percent, so that heavy trains can be handled over the line with perfect safety and good speed." A special trip for shippers was made over the line "on Friday," who praised the manner with which the road had been built. Boston Consolidated had been trying to market 500 tons of sulphide ore per day, but had been unsuccessful due to the inability of the Copper Belt road to keep the company supplied with cars to its sulphide ore bins in Carr Fork. The completion of the Sky Line would allow Boston Con to ship 500 tons of ore every day without problem. Utah Copper company would now be able to move forward with its plans to begin treatment of porphyry ores at its new Garfield mill, starting on March 1st. (Salt Lake Herald, January 27, 1907)

(Salt Lake Mining Review, October 30, 1911, p. 18, reported that the first day of operation was January 2, 1907)

January 27, 1907
"The Rio Grande Railroad company's new high line at Bingham will be opened for traffic Monday." ("Monday" was January 28, 1907) "The present output of Boston Consolidated should be 500 tons a day, but its actual output has been 200 to 300 tons a day because that was all the railroad could handle." "The Sky Line, as it is called, is completed as far as the Utah Copper company's mine, and hereafter all ores from the upper part of the district will be moved over the new track, only such ore as are needed to keep the Yampa smelter and the Utah Copper mill in operation being brought over the Copper Belt line below the point of junction of the two lines." "The maximum grade of the Sky Line from the Utah Copper plant to Garfield Junction does not exceed 2-1/2 percent., it is said. The railroad company has built a switching yard just below the Utah Copper mine. Four tracks have been laid, which will suffice for the present, but as the big steam shovels tear down the mountain side the yard will be enlarged." (Inter-Mountain Republican, January 27, 1907, "Bingham Sky Line Open For Traffic")

The line was not formally completed and turned over to the operating department until February 1907. (Mines and Minerals, May 1908, p. 454)

(Other sources, including 26 ICC 809; Arrington and Hansen, The Richest Hole on Earth, 1963, p. 55; and the Utah Copper 1906 Annual Report, mistakenly state that the line was completed in April 1906, the date construction started.)

When the new Cuprum yard was completed in 1907, it included numerous buildings needed for the operation of a busy railroad yard, all placed on the mountain side. Within five or six years, the railroad built a large hotel owned by the railroad but operated as a boarding house. Photos dated 1914 show the building, but earlier photos do not. Its purpose was to provide a place for railroad employees to stay between their shifts while away from their homes down in Salt Lake Valley. When the tracks and yard were sold to Utah Copper in 1925, the railroad hotel was also sold, and was operated as a hotel for anyone. The difficulty was that there was no access except by a steep trail up from Bingham, hundreds of feet below.

As part of the same expansion of railroad line capacity that saw the construction of the Low Grade Line, in August 1905 Rio Grande Western began work on the construction of a new branch to Garfield, to serve the new Utah Copper concentration mill, and the new ASARCO smelter. (Salt Lake Mining Review, August 15, 1905, p. 31) The new line would be built from a connection with the Bingham Branch at a new station called Garfield Junction (later Welby), and continue northwest to the new smelter site at Garfield, and was completed in November. (Salt Lake Mining Review, October 31, 1911, p. 18)

The new Garfield Branch (sometimes called the Garfield Beach Extension) connected with the Bingham Branch at a new station called Garfield Junction, later renamed Welby after A. E. Welby, the General Superintendent of the combined Rio Grande Western/Denver and Rio Grande system. The 16 mile Garfield Branch was completed to the new smelter site in November 1905 and work on the expansion project was stopped for the winter. Construction resumed the following April, with the grading work on the Low Grade Line.

On April 19, 1907 Utah Copper shipped its first train of low grade copper ore to its new Magna mill, by way of the new Low Grade Line and the new Garfield Branch. (Kennecott Historical Index)

After the completion of the Rio Grande Low Grade, taking all of the high-volume traffic from Utah Copper and Boston Consolidated, and taking the pressure off of the Copper belt line, the Copper Belt was kept busy by shipping ore from the other mining companies down to the concentrating mills (Markham mill and Dewey mill). There was also plenty of small shipments (two, three or four cars daily) from the smaller mines that shipped their ore direct to the smelters, through the connection with RGW at Bingham station. These small shipments continued well into the early 1920s, until the upper portions of the Copper Belt, as well as the upper portions of the Rio Grande Low Grade line itself, were in the way of the expanding Utah Copper open pit mine. Utah Copper bought a large portion of the Low Grade line, which it used as part of its waste rock dump lines. With the closure of the small concentrating mills in the 1919-1920 time period, the Copper Belt was essentially abandoned above the Montana-Bingham tunnel, leaving it as just a spur, less than a half-mile up-canyon from the Bingham depot. This spur to the Montana-Bingham (later Bingham Mines) loading bins remained in place until the early 1940s.

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