The diesel locomotive, able to pull more cars with fewer locomotives, was introduced in the 1940s, reducing the need for rail hubs with service facilities in towns like Pendleton. After the formation of Amtrak in 1971, Union Pacific abandoned passenger service altogether and built a large railroad yard 30 miles northwest of Pendleton, moving most of its operations there. The Pendleton depot became a freight agency with a single agent on duty to handle local business. Later, improvements in technology brought about further consolidation of railroad operations and eventually eliminated Pendleton's freight agent's office, leaving the depot vacant and its future uncertain. The Pendleton depot is a red brick building laid in flemish bond.
Shallow pilasters define each corner and divide paired win- dows.
Walls are stepped out just above ground level. The hip roof is decorated with small gables at each end of the ridge. Typical of depots from the period, the roof has a double pitch and canopy. Red pipe designed to look like terra cotta tile covers the roof. Corbeled wood brackets support wide overhanging eaves to protect passengers, baggage and railroad workers from the weather.