With electrification thus a very real technical possibility, and with the problems of steam operations all-too-frequently demonstrated, research was begun in 1912 to determine the feasibility of electrification from Harlowton to Avery and the most advantageous system to adopt.
After this exhaustive study of all the factors and possibilities was completed, the board of directors voted to electrify with a 3,000-volt, direct current, overhead supply system.
On the railroad’s board of directors at this time was John G. Ryan, president of the Anaconda Copper Mining Company and a director of a local power company. Ryan’s interests in these inter-related fields undoubtedly helped sway the rest of the board toward electrifying, and his special expertise and influence helped ensure that it would be done smoothly and efficiently.
Late in 1912, the first contract for power supply was signed with the Montana Power Co. Work on the electrification began in April of 1914.
On November 30, 1915, the trolley wire was energized for the first electrically-operated train to run on the Milwaukee Road, a 112-mile special from Three Forks to Deer Lodge, Mont. Electrical operations were gradually extended over the entire line from Harlowton to Avery, and steam locomotives were almost completely supplanted by the end of 1916. Full electrified operation from Harlowton to Avery began in early 1917.
From the outset, the electrification was far more successful than had been anticipated. With this success, authorization was quickly given in 1917 to electrify the Coast Division from Othello to Tacoma, Wash. On this line through the Saddle and Cascade Mountains, tunnels, curvature and snowfall made steam operation difficult for a large part of the year. The steepest grades on the mainline are also on the Coast Division.
Quite naturally, the same electrical system was chosen, and by the fall of 1919, electrical helper service was started on several of the grades. The line to Tacoma was completely electrified by March of 1920, and the last leg, a nine-mile section from Black River Junction, Wash., into Seattle, was electrified in 1927.
Research was begun
Trolley wire energized (Three Forks to Deer Lodge)
Electrified operation from Harlowton to Avery
Authorization given to electrify the Coast Division
Electrification to Tacoma completed
Dropped plans for electrifying the gap
Last leg electrified