Historic Bridge - Thayer Viaduct

Thayer Viaduct , Oregon County, Route 19

Click HERE to see photos of this bridge.

Bridge Location  

County: Oregon
Road: Route 19
Feature Crossed: Two Mile Creek and BNSF Railroad 
Other Location Information: approximately 1.25 miles north of Naylor
Structure Number or County Bridge Number: Bridge No. H0289 

Bridge Information 

Owner: MoDOT
Type: 1 pin-connected Pratt through truss and 2 rigid connected Warren pony trusses
Length: 305’ total length; 155’ through truss, 74’ and 75’ pony truss 
Width: 20’ wide roadway with 5' sidewalk cantilevered on east side of bridge 
Year Built: 1930
Builder: M. S. Cartter & Co., St. Louis (through truss), Martin Wunderlich (substructure & approaches) 
History of Modifications, Rehabilitations, etc.: Sidewalk added in 1949 

For further information, interested parties may contact

Name: Karen Daniels, Sr. Historic Preservation Specialist  
Organization: Missouri Department of Transportation  
Address: MoDOT Design Division, Historic Preservation Section, P.O. Box 270, Jefferson City, MO 65101
E-Mail: Karen.daniels@modot.mo.gov 
Phone: 573-526-7346 

Narrative Description

The Thayer Viaduct (H0289) consists of a steel, eight-panel pin-connected Pratt through truss with two six-panel rigid-connected Warren pony truss approach spans on the north end. The sidewalk is cantilevered on the east side of the bridge and has a wooden deck and a chain-link fence.

The bridge is eligible for the National Register of Historic Places under criteria A and C for its significance in transportation and engineering. The Thayer Viaduct was cooperatively built by the Missouri State Highway Department and the Frisco Railroad during a time when an effort was being made to reduce at grade crossings to improve highway safety. The cost of the viaduct was shared between the two parties and the federal government. The through truss was designed by the Frisco Railroad and reflects structural features common for both highway and railroad trusses of the era. The pony truss approach spans were standard Missouri State Highway Department designs.

MoDOT’s Historic Preservation Section is now accepting proposals for the relocation and reuse of the bridge until December 31, 2018. A proposal checklist is available MoDOT’s Free Bridges website (http://www.modot.org/freebridges/). Preservation covenants may accompany the bridge.