UP-LA&SL Frisco Branch

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This page was last updated on January 31, 2023.

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Union Pacific's Frisco Branch extended from Milford, in central Utah, west to the mining town of Frisco. It was completed in 1880, and an extension to Newhouse was completed in 1904. Milford was on the mainline as a local road, Utah & Pacific, built south toward California in 1899.

In 1901 the mainline south from Milford to California passed to Oregon Short Line, a direct subsidiary of Union Pacific. Since 1889 the Frisco Branch had been in UP hands, as part of UP-subsidiary Oregon Short Line & Utah Northern, then as part of Oregon Short Line in 1898 after the Union Pacific reorganization.

In 1903 the Frisco Branch, and the mainline south from Milford, was part of the sale of everything south of Salt Lake City to the San Pedro, Los Angeles & Salt Lake Railroad, the railroad between Salt Lake City and Los Angeles, formally completed in 1905. Although closely aligned with Union Pacific, the SPLA&SL was actually owned half and half by Union Pacific interests, and other interests in California.

Union Pacific increased its percentage of control and in 1921 purchased full control of what was known as the "Salt Lake Route," by this time going by the formal name of Los Angeles & Salt Lake Railroad. To cut costs of its large system of railroads, in 1936 Union Pacific formally leased three of its largest subsidiaries, including LA&SL. The lease allowed centralized management and improved system-wide operations. The lease remained in place until 1987 when all subsidiary roads were formally merged into Union Pacific.

Throughout all the ownership changes, the Frisco Branch, and its connected Newhouse Extension, continued feeding limited (and declining) mining and agricultural traffic to the mainline at Milford.

Mile Posts

(from LA&SL drawing 562-8, dated January 1907; examined at UP Depot Annex, Salt Lake City, Utah, April 29, 1988)


January 11, 1879
The second Utah Southern Railroad Extension was organized to build south of York, to the Horn Silver mine at Frisco. (Reeder, p. 139; Athearn, p. 280)

June 23, 1880
Utah Southern Railroad Extension tracks completed to Frisco, 137.24 miles from the Utah Southern connection at Juab. The next day the railroad began shipping ore from the Horn Silver Mine. (Salt Lake Herald, June 25, 1880; Reeder, p. 143; Athearn, p. 280)

September 16, 1887
"The Utah Central road has closed its Frisco freight, ticket and telegraph offices, as they don't pay. Trains will run up there from Milford just the same, but all the clerical work will be done either at Milford or by the conductors." (Salt Lake Daily Tribune, September 16, 1887)

July 7, 1903
San Pedro, Los Angeles & Salt Lake Railroad purchased from OSL the following segments: Sandy to Frisco, 226.07 miles; Milford to Caliente, 115.08 miles; Lehi Junction to Tintic, 43.27 miles; Salt Lake City to Leamington Junction, 115.45 miles; and various mine spurs, 12.46 miles. (Union Pacific internal history of LA&SL, on file in Salt Lake City public relations offices; copied on January 20, 1978)

September 1904
SPLA&SL completed the 5.96-mile Newhouse Extension, from Frisco on the Frisco Branch to Newhouse, to serve the copper mine that was being developed near there. The line was surveyed in February 1904. (Salt Lake Mining Review, February 29, 1904, page 36) Construction was begun in June 1904, using $99,688.65 advanced for the purpose by Samuel Newhouse, owner of Newhouse Mines & Smelters. (SPLA&SL corporate history; Salt Lake Mining Review, April 30, 1904, page 36)

February 27, 1925
LA&SL received Utah Public Utilities Commission approval to discontinue regular service between Frisco and Newhouse. The line was constructed in the latter part of 1904 for the Newhouse Mining Company and the Cactus Mining Company. By 1925 the town of Newhouse had been dismantled and the railroad's only traffic was tank cars of water for the local sheep ranches. (Public Service Commission of Utah, case 741)

A check of newspapers finds that the mill at the newly active Horn Silver mine was not being used in 1929, and that ore was being shipped directly to the smelter. A summary of numerous newspaper reports follows.

By mid April 1929 Union Pacific was busy rehabilitating its spur tracks in anticipation of large shipments. However, it appears that the concentrating mill was not to be put into operation, with all ore coming out of the mine and being shipped directly to area smelters. A total of 15 carloads had already been shipped by leasers who were busy rehabilitating and extending the various tunnels and shafts. The mine company itself had been involved in straightening and expanding the main hoist shaft, and installing a modern triple-compartment hoisting system. A newspaper report for April 21, 1929 shows that the mine company had spent $250,000 putting the surface plant "into perfect order." This included a steam-driven hoist, machine shops, sawmill, electric gear, an assay office, and a blacksmith shop. The 150-ton mill located on site was in running order, "but will not be used, inasmuch as the ore can be profitably shipped without treatment."

In 1937 Union Pacific's depot was the only structure remaining in Newhouse and at Frisco there was only the railroad's depot and two houses. Work on removal of the Newhouse Extension was begun on September 10, 1937.


In 1937 the railroad had applied to abandon the entire Frisco Branch, along with the Newhouse Extension. But the ICC imposed a two year test period, at the suggestion of the Utah State Industrial Development Board, to allow development of potential mine traffic, from Frisco to Milford. (Abandonment approved by the ICC in Finance Docket 10623, effective May 22, 1937, in 221 ICC 309)

October 7, 1937
LA&SL completed removal of the seven-mile Newhouse Extension, Mile Post 16.5 (Frisco) to Mile Post 23.5 (Newhouse, end of branch) of the Frisco Branch. The removal was done under Work Order 934. The Newhouse Extension had been completed in September 1904 to connect with Samuel Newhouse's Newhouse Mines & Smelting mill railroad, the Newhouse, Copper Gulch & Sevier Lake Railroad, which shut down in 1927.

The Newhouse Extension was an extension of the Frisco Branch. Regular service on the Frisco Branch had ended in 1931 with the shutdown of the old Horn Silver mine by the Tintic Lead Company, which had bought the property in 1928. The Newhouse Extension was washed out in several places during 1934 and 1935. Passenger service to Newhouse had ended in 1928.

August 28, 1943
LA&SL completed removal of 15.29 miles of the Frisco Branch, from Mile Post 1.21 to Mile Post 16.5 (Frisco, end of track). The branch was retired on June 22, 1943, after abandonment was approved by the ICC on July 24, 1942. (Work order 2528; ICC Finance Docket 13611, effective September 24, 1942)

The federal ICC had approved the abandonment of the Frisco Branch on July 24, 1942. (252 ICC 803, Finance Docket 13611; Decided July 24, 1942, "Cases Disposed Of Without Printed Report")


UP/LA&SL Frisco Branch - A Google Map of the Frisco Branch. Milford to Frisco (17.4 miles), and from Frisco to Newhouse (6.9 miles).


The request to abandon the Frisco Branch, and the Newhouse Extension in 1937 was denied. The ICC published the denied request in its printed reports, in 221 ICC 309.

The request to abandon the Frisco Branch in 1942 was approved. The ICC did not publish its decision for Finance Docket 13611 in either its "Printed Reports," or as one of the "Cases Not Printed" at the back of its printed reports.

Below are PDF versions of some of the documents furnished as a courtesy by the ICC to the State of Utah, and which are in the Utah State Archives.


Compiled from handwritten notes, dating from 1978-1988, with recent updates from other material.

Most of the original information here was transcribed from handwritten notes taken while doing research in the files of UP's engineering department during 1982-1983, then compiled as a computer file in 1988, with additions through September 1994. Other updates and additions made after creation of web page in 2015.

The notes from the early 1980s were completed prior to the closure of UP's engineering office in Salt Lake City in about 1984. All files and most personnel were moved to Omaha in 1983-1984. The office was located in the Utah Division offices in the former depot annex building, just south of Union Pacific's Salt Lake City depot. The building was demolished in 1999 to make room for The Gateway Project.