Eagle Rock Substation Looking North

Eagle Rock Substation Looking North

The Eagle Rock Substation was the endpoint of the transmission lines stretching from the Big Creek to Los Angeles, initially spanning 240 miles and operating at 150,000 volts (Cox and Michener, 1). Construction started in February 1913, and this photo was taken in August 1913, when construction was partially complete. The transmission lines became fully operational in December 1913, supplying Los Angeles with 60,000 kilowatts of electricity, or 20% of the city’s electricity (Fredericks, 350). Though 85% electricity went to running Pacific Light & Power’s (PL&P) street railroads, the rest was sold to business and residents (Friedricks, 351).

As early as the 1910s, Caltech was already involved in the issue of electricity transmission to Los Angeles, via Professor Royal W. Sorensen, who served as a Consulting Engineer for PL&P from 1913 to 1917 (“Orange and White”). Part of his work as Consulting Engineer involved conducting experiments on PL&P infrastructure, such as the resistance of water jets at Eagle Rock (Royal W. Sorensen).

Sorensen’s connection to Eagle Rock extended beyond his official role as Consulting Engineer. In April 1920, Sorensen led a field trip of senior Electrical Engineering students to the substation (“Orange and White”). As reported in the Orange and White book of 1919-1920 (Caltech’s student yearbook at the time), “Mr. Sorensen had done considerable work in the station and on the Big Creek transmission and was therefore able to accurately explain many details of the equipment,” further verifying Sorensen’s extensive work on transmission (“Orange and White”).

Sources:

Friedricks, William B. “A Metropolitan Entrepreneur Par Excellence: Henry E. Huntington and the Growth of Southern California, 1898-1927.” The Business History Review, vol. 63, no. 2, 1989, pp. 329–55. JSTOR, https://doi.org/10.2307/3115699.

“Orange and White : A History of the California Institute of Technology, 1919-1920.” Big T [Pasadena, CA], Caltech Student Yearbook, nos. 1919–1920, 1920, https://resolver.caltech.edu/CaltechCampusPubs:20110726-143937916.

Royal W. Sorensen. “Water Jets: Eagle Rock Substation, Undated.” circa 1913, Caltech Archives, Royal W. Sorensen Papers, Box 1, Folder 2.

Woodbury, Edward. “150,000-Volt Transmission System.” Transactions of the American Institute of Electrical Engineers, XXXIII, no. 2, June 1914, pp. 1283–98. IEEE Xplore, https://doi.org/10.1109/T-AIEE.1914.4765183.

Stone & Webster Inc.

Southern California Edison Photographs, Huntington Library
https://hdl.huntington.org/digital/collection/p16003coll2/id/59565

1913-09

Photograph

Photograph