The southbound Winchester Bridge on Interstate 5 is a 17-span structure consisting of five 141.5-foot main span steel Warren deck truss spans. The four span north approach is made up from a singe 40-foot simply reinforced concrete girder span and three approximately 82-foot pre-stressed girder spans. The south approach consists of eight 82.0-foot pre-stressed girder spans. The roadway is 30-feet wide which carries the two 12-foot southbound lanes.
The overall design of the structure replicates the earlier northbound bridge that was constructed in 1955. The bridge was designed by Oregon State Highway Department bridge designer T.C. Roake under the guidance of State Bridge Engineer Ivan D. Merchant.
Length of largest span: 141.5 ft.
Total length: 1,621.7 ft.
Deck width: 30.0 ft.
Approximate latitude, longitude
+43.28194, -123.35583(decimal degrees) 43°16'55" N, 123°21'21" W (degrees°minutes'seconds")