National Museum of Transportation near Kirkwood in St. Louis County, Missouri — The American Midwest (Upper Plains)
Union Pacific #900081
1966
Designed and built by the Union Pacific Railroad in the Omaha Shop, this rotary snowplow is the heaviest ever built weighing 367,400 lbs. Its cutting wheel could throw snow far to either side of the track as it was pushed forward at four to six mph. It is not self propelled and must be pushed by 3 or 4 locomotives. Number 900081 is powered by a GM/EMD 16 cylinder, 2,000 hp turbocharged diesel engine that drives an electric generator which provides power to turn the 12' rotary blades at up to 150 rpm. A steam generator heats the cab, prevents the fuel and water pipes from freezing and can thaw out the cutting wheel if it gets struck. The plow engineer controls both the plow and the trailing locomotives. This snowplow is 52'2" long, 17' high, and was last used in Green River, WY, in the mid-1980's. The circular windows in the front of the plow revolve to keep them clear of snow.
Donated in 1994 by the Union Pacific Railroad
Erected by Museum of Transportation.
Topics. This historical marker is listed in this topic list: Railroads & Streetcars. A significant historical year for this entry is 1966.
Location. 38° 34.333′ N, 90° 27.664′ W. Marker is near Kirkwood, Missouri, in St. Louis County. It is in National Museum of Transportation. It can be
this page online
Regionally, this marker is in Greater St. Louis. It is also in the American Midwest, in the Lewis & Clark Corridor, in the Corn Belt, and in the Great River Road Region. Globally, it is in North America, the Western Hemisphere, the Western World, and the Anglosphere. Historically, it finds itself in what was once the Viceroyalty of New France, the territory of the Mississippian Culture, the Louisiana Purchase, and the Antebellum South.
Other nearby markers. At least 8 other markers are within walking distance of this marker: Union Pacific "Big Boy" #4006 (a few steps from this marker); Union Pacific #6944 (a few steps from this marker); Chesapeake & Ohio #2727 (within shouting distance of this marker); Illinois Central #30 (within shouting distance of this marker); General Motors #103 (within shouting distance of this marker); Atchison, Topeka & Santa Fe #5011 (within shouting distance of this marker); Jay Gould and the Missouri Pacific (within shouting distance of this marker); The Pacific Railroad of Missouri: Audacious Dreams & Harsh Realities (within shouting distance of this marker). Touch for a list and map of all markers in Kirkwood.
Photographed by Garrett Koch, November 14, 2025
3. Union Pacific #900081
End view of the #900081 U.P. model showing the rotary snowplow in front. This "dummy" engine was equipped with a 16-cyl 3000 h.p. turbocharged diesel engine but that only powered the huge 12' dia cutting wheel at up to 150 rpm. The snowplow required at least 3 diesel engines to push it through the snow drifts, sometimes even taller than the plow.
Credits. This page was last revised on June 1, 2026. It was originally submitted on April 28, 2019, by Devry Becker Jones of Washington, District of Columbia. This page has been viewed 260 times since then and 20 times this year. Photos: 1, 2. submitted on April 28, 2019, by Devry Becker Jones of Washington, District of Columbia. 3. submitted on May 31, 2026, by Garrett Koch of Saint Louis, Missouri.
