This bridge is not part of the Gateway Trail, which runs to the north along the former Soo Line passenger line. This is a former Northern Pacific branch line between White Bear Lake and Stillwater. It was most recently used for the Minnesota Zephyr dinner train, which ceased operation in 2008.
All is not lost for this bridge, however. The line was recently sold to the Minnesota DNR, which is currently constructing the Browns Creek Trail along the right of way. This trail will split off the Gateway Trail at the former Soo/NP railroad junction (Duluth Junction) and run across this bridge into Stillwater. The new trail will hopefully be open to bike and pedestrian traffic in 2015.
http://www.dnr.state.mn.us/state_trails/browns_creek/index.h...
The Browns Creek Trail opened to pedestrian and bicycle traffic on Thursday, October 30, 2014. This bridge is now in service once again.
http://stillwatergazette.com/2014/10/30/browns-creek-trail-n...