Major upgrade of Union Pacific’s rotary snow plows

By Jerry Blackwill
(reprinted from the Truckee Donner Railroad Society’s quarterly newsletter)

The Truckee Donner Railroad Society’s rotary snow plow is about to become even more of a historic artifact. Union Pacific is rebuilding its rotaries in a way that will change the appearance of the snow removal machines. The change was prompted by last winter's heavy snows. Over 58 feet of snow fell on Donner Pass making it one of the tenth snowiest winters since 1879. The rotaries are the third line of defense in the railroads’ war against these winter storms.

The first line of defense when snow covers the rails are the yellow, caboose-like flangers. A flanger is so named because a "flange" drops down between the tracks to clear snow from between the rails. When it begins to snow, these short trains run as fast as thirty five miles per hour between Truckee and Blue Canyon clearing the rails of snow. The first sign of trouble last winter was when a flanger was derailed by a heavy accumulation of snow.

The second line of defense are spreaders with large "wings" on the side of the units that spread the snow out from the rails. The blades normally keep the snow clear for some distance from the tracks. Most winters this is all that's required as the flangers and spreaders can keep the line sufficiently clear to provide for continued railroad operation.

Last winter, spreaders were running twenty-four hours a day, seven days a week. They were pushing snow as high as the cab of the spreader and still appeared to be losing the battle. When a flanger was caught in an avalanche west of Cisco, the Union Pacific had no choice but to bring the rotaries out. Even then, it took over a day to open the Union Pacific's main line over the Sierra. The rotaries hadn't been used since 1998 because snow levels during that period were such that the flanger/spreader combination was sufficient to keep the tracks clear.

After experiencing the heavy snows of 20 l0-20I l, Union Pacific decided it was time to upgrade the three Roseville rotaries. They are being sent back to the Relco locomotive rebuilding facility in Albia, Iowa. This will be the first major upgrade in over 60 years. The entire top section of the rotary will be replaced and new steam generators will be installed. The engineer's visibility will be improved by placing his position in the center of the cab. The center window is clearest because the rotary blows snow to either side. Lastly, the latest electronics will be added to allow the rotary to be controlled at very low speeds.

Because new parts have not been available, rotary SPMW 207 became the source of spare parts for the other two rotaries. It will be the first of the three rotaries to be upgraded. Recently, large cranes in the Roseville yards lowered
SPMW 207 on a special low-center flat car for rail transport back to the Iowa rebuilding facility.

Thanks to Brendan Compton of BA Productions for his comments describing the rotary upgrades and railroad operations in the winter of 20l0 - 201 l.

Railroad Society Rotary

Spreader

Flanger

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