BNSF Snowden Bridge

 bridge, railway bridge, vertical-lift bridge / lift bridge

Construction of the Snowden bridge, and a twin 10 miles to the south at Fairview crossing the Yellowstone River, began during 1912. These bridges were to be part of the Great Northern Railway's Montana Eastern Railway, which was never completed. The Missouri was deemed navigable at the time of constuction, resulting in a lift span as part of the structure. Last raised during 1935, it is now inoperable. The Great Northern was merged into Burlington Northern during 1970, which in turn became BNSF Railway. Watco's Yellowstone Valley Railroad began operating the line and the bridge on August 15, 2005 through a long term lease. America's railroads built 32 crossings over the Missouri River, of which 23 remain in use.
www.johnweeks.com/upper_missouri/pages/mt_mo_01.html
www.midrivers.com/~fairview/bridges.html
cs.trains.com/forums/1173753/ShowPost.aspx