The Pacific Extension was the successful attempt by the Chicago, Milwaukee and Saint Paul Railroad (the Milwaukee Road) to build a transcontinental line over the Rocky and Cascade mountain ranges and reach the Pacific Northwest, specifically the Seattle area. Construction on the line began in 1906 and completed in 1909; the line represented the shortest route over the Continental Divide. Upon completion, the name of the CM&StP was changed to the Chicago, Milwaukee, Saint Paul and Pacific Railroad, adding "Pacific" to the name in order to identify its extents. This route was the last of the great transcontinental routes to be constructed in the United States.
Due to the northern regions through which the line traveled, the Milwaukee Road found that electrifying various parts of the Pacific Extension produced more favorable results than the usual steam power that was typically found elsewhere during that time. At the height of electrification, 656 total miles along the extension were electrified (albeit in different locales and therefore disconnected), making the Milwaukee Road the largest electrified railroad in the US. It dismantled its electrified infrastructure in 1973, during the onset of the oil crisis -- as diesels started roaming in previously electrified territory and with oil prices soaring, the de-electrification of the Milwaukee Road ultimatley proved ill-timed.
Because of the Milwaukee Road's increasing financial woes during the 1970s, the track along the Pacific Extension slowly deteriorated due to lack of funds for maintenance. The road's bankruptcy in 1977 ultimately spelled doom for the Pacific Extension, and it was abandoned west of Miles City, MT, in 1980.
Thanks to Mike Fromholt for contributing information.
In the game, Trainz RailRoad Simulater, onw of the routes was about Milwauke Road's Avery-Drexel and BN/NP's Lookout Pass, I could trace the missing part of them in Idaho. :)
I used Google Earth and tracked the entire route of the old Milwaukee Roads tracks between Butte MT and Miles City,MT. On Google Earth there are numerous photo Icons that will give you photos of old Depots, signals, train cars on static display, bridges and tunnels and even a roundhouse and shop complex among other things along this route that are still easily discernable and visible as you "mouse" along the route. Once I got started I just couldn't stop until I had traced the entire route. It is such a same that this route was abandoned and the tracks ripped up. Some of it is obviously some of the most beautiful terrain that would have made a wonderful Scenic Excursion route. Admitted ly some of the landscape was flat and featureless but it would have been a wonderful ride. The little towns and small locals obviously would have never existed unless the Railroad had first come through. Now that it is gone, many of them have dreid up as well. I've also tracked other defunct routes using Google Earth as well. On this one....just start in Butte going east or Miles City moving west. Enjoy railfans!
Greg Perry Sr.
There are remnants of a viaduct near Lind, WA. It passed over the BNSF (former NP) at that location. The Portland section of Amtrak's Empire Builder travels that former NP route between Pasco and Spokane, WA; the remnants of the Milwaukee viaduct are clearly visible from the train.
The bridge over the Columbia River, at Beverly WA is still standing. This was an electrified structure. On the west end, there was a junction for a branch to haul materials to the dam just downstream. Older stories was this branch went all the way to the northern part of the Hanford Nuclear facility. So many stories of the Milwaukee Road in the West.