SPLA&SL / LA&SL Concrete Roundhouses

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This page was last updated on November 2, 2021.

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The San Pedro, Los Angeles & Salt Lake Railroad (Los Angeles & Salt Lake Railroad after 1916) operated all UP lines south and west of Salt Lake City, Utah.

In 1915, 1916 and 1917, LA&SL completed three locomotive roundhouses in Utah. These were a 10-stall addition to the existing 8-stall brick roundhouse at Lynndyl in 1915, a 10-stall addition to the existing 10-stall brick roundhouse at Milford in 1916, and in 1917, the new 7-stall roundhouse at Provo that was used jointly with Utah Railway. All were made of precast, reinforced concrete panels, beams and columns that were formed and poured on site, then assembled using cranes that lifted the components into place. The concept and design was first used as early as 1909, and was patented in 1910 and 1912 by the Unit Construction Company of St. Louis, using the "Unit-Bilt" trademark. The three roundhouses on the LA&SL in Utah were built by the Van Sant-Houghton Company of San Francisco.

These three concrete roundhouses were reported in the trade press at the time to be identical, or at least very similar to roundhouses built for AT&SF at Riverbank and Redondo Junction, California.

Lynndyl Roundhouse

UP retired most of the Lynndyl roundhouse in 1948, after the LA&SL was dieselized. The Lynndyl roundhouse was one of three pre-cast concrete roundhouses on the LA&SL: Lynndyl in 1915; Milford in 1916; and Provo in 1917.

UP Lynndyl Roundhouse Letters -- A compilation of letters from 1939-1943, concerning proposed retirement of portions of UP's Lynndyl roundhouse. (PDF; 18 pages; 11.3MB)

UP Lynndyl Roundhouse Drawing -- A drawing showing what was later retired in May 1948.


The Lynndyl roundhouse addition was constructed in 1915 and was reported as being unique because it was constructed during the winter season. The precast components were completed prior to the cold temperatures setting in, and assembled after winter weather had begun.

September 1916
A news item about Mr. Shirley Houghton becoming the sole owner of the Van Sant-Houghton Co., builder of specialty reinforced concrete structures, included the following: "Of the work now in hand, the following will be completed on or before September 1st." "Construction of reinforced concrete Unit-Built roundhouse for S.P.,L.A.&S.L. R.R. Co. at Milford, Utah." (The Architect and Engineer magazine, Volume 46, Number 2, August 1916, page 133; courtesy of Ed Workman, email dated August 4, 2016)

November 1916
LA&SL announced that they would enlarge the Milford roundhouse. (Salt Lake Mining Review, November 15, 1916, page 33)

The Provo joint shops were begun in March 1917, and the roundhouse and machine shop was completed in November 1917.

July 1917
Houghton Construction Co. was building a roundhouse at Provo. (Beaver County News, July 27, 1917) (as part of a new joint terminal with Utah Railway)

Early October 1917
The new, modern concrete Provo roundhouse was under construction in early October. (News-Advocate, October 12, 1917)

Mid October 1917
The new Provo Joint Shops was just about complete. The new facilities included a double coaling trestle, a water tank, a ninety-foot turntable, and a new roundhouse and machine shops. During the second week of October, the roundhouse roof beams were erected. (The Sun, October 12, 1917, page 8, "Utah Railway's Terminals About Completed At Provo")


Here are four photos of the Provo roundhouse, taken by Dean Gray.

(View four Dean Gray photos of the Provo roundhouse)

And here is another photo of the Provo roundhouse, by Dave England.

(View a Dave England photo of the Provo roundhouse)