Shoshone Transmission Line, Colorado

1951-1952 Upgrade

[Trade Journal]

Publication: "Lines" - Public Service Company of Colorado

Denver, CO, United States
vol. XI, no. 2, p. 7, col. 1 - 2

Thomas A. Edison Figured in Construction of Historic Shoshone

Transmission Line Now Undergoing Extensive Rehabilitation.


Colorado's historical Shoshone electric transmission line, in the design and construction of which Thomas A. Edison's counsel and techniques were employed, is in the final stages of a program of rejuvenation. Renewal and replacement work on the 46-year-old circuit, which spans the lofty Continental Divide on its 153-mile route between the Colorado River and Denver, was started more than a year ago. With the advent of winter, work as halted until next spring.

The first transmission line in the state that was strung on steel towers, it reaches an altitude of 13,525 feet where it crosses Argentine Pass, between Dillon and Idaho Springs. A total of 1,100 of these towers carry current from the pioneer Shoshone plant near Glenwood Springs. Very few of these sturdy towers have been replaced since their parade across the Rockies was started in 1906, despite snowslides, floods, and high winds.

The six-strand copper cable with a core of hemp which has so efficiently served since its installation on the three-phase line is being replaced with aluminum and steel cable.

The 100,000-volt Shoshone line has been the medium for the transmission of approximately 3,500,000,000,000 kilowatt hours of electricity in its half-century of operation. In its early stages the line was utilized by Edison and his associates, F. W. Peek and Guiseppe Faccioli, for a series of experiments in the transmission of electricity over long distances and in the effort to combat lightning.

The Shoshone line, which follows the Frying Pan River to 12,200 foot Hagerman Pass, parallels the abandoned route of the famous old Colorado-Midland-Phantom Canyon railway, first railroad to tunnel through the Continental Divide. The Midland was junked three decades ago. The existence of the Colorado-Midland furnished the incentive for building the Shoshone line along the route it follows. The railroad was utilized to haul heavy duty cable and steel tower materials through the Rockies to Basalt, Colorado, construction headquarters for line crews of the old Central Colorado Power Company, a predecessor of Public Service Company.

The Shoshone line includes one section of cable that rises straight up into the sky. Between Shoshone plant and the top of the canyon, the line ascends a height of 3,000 feet, up sheer granite cliffs.


Keywords:Power Transmission
Researcher notes: 
Supplemental information: 
Researcher:Glenn Drummond
Date completed:November 27, 2006 by: Glenn Drummond;