Norris ViaductSubmitted by the City of Cheyenne
One dominating feature of Cheyenne is Union Pacific Railroad’s busy Overland Route mainline and its associated rail yard. With a frequency approaching 80 trains per day, it is a significant barrier to transportation within the city. Consequently, the city and Union Pacific have been working together since the 1880s on grade-separated crossings.

The original Norris Viaduct was constructed in 1952 on what was then the east edge of town. For many years, this two-lane steel and concrete structure was part of the main east-west truck route through Cheyenne. With the completion of Interstate 80 in the 1970s, it no longer filled the role of primary truck route; however, it continued to carry more than 13,000 vehicles per day.

By the 1990s, it was becoming increasingly apparent that the structure was reaching the end of its lifespan. Many elements, including railings, sidewalks and surfacing, did not meet current standards and could not be easily upgraded.

This project changed the area dramatically—and the lives of people who live nearby. By replacing the viaduct and widening and reconfiguring the streets, the project improved safety; rerouted a storm sewer; and created a buffer area between the refinery and a residential area with an under-crossing for safe pedestrian passage.

Cheyenne, Wyo.

$28.2 million
Owner: City of Cheyenne
Contractor: Reiman Corp.
Engineers: Olsson Associates, Cheyenne Board of Public Utilities
Among the Subcontractors: AVI, WYDOT Right-of-Way Section, Utah Pacific Bridge & Steel, Knife River, Aztec Construction Co. Inc. Frontier Refining Inc.
Start: July 2008 Finish: Oct. 2009