The Oliver Bridge was built as a swing span bridge. It had a long metal trestle, with a 300 foot long swing span located near the Wisconsin side of the bridge. A narrow two lane highway deck was constructed under the railroad deck. Since there were large concrete abutments on each end of the bridge, the highway deck had sharp 90 degree corners on each end of the bridge. For most of the life of the bridge, the highway deck was made out of timber and wooden boards, making the crossing very spooky. The rail deck once supported twin tracks, but a section of the eastbound track has been removed at each end of the bridge. This appears to have been done to allow more light to shine on the very dark corners of the highway deck. The bridge was closed in 2001 and 2002 to allow MN-DOT and Wi-DOT to work with DM&IR to replace the highway deck with a concrete floor and guardrails.
While the Oliver Bridge was built as a swing span, there is no evidence that it ever operated as a working swing bridge. The Duluth harbor was never extended past the Gary New Duluth steel mills and furnace complex. The river is not readily navigable beyond the bridge. The bridge was opened in the 1960s as part of a pipeline project. It reportedly took 3 days of work to get the bridge open. Since work was done on the bridge in 1970, it appears that it is no longer possible to open the swing span.
The bridge was owned for many years by the Duluth, Missabe, and Iron Range Railroad. The DM&IR sold out to the Canadian National on May 10, 2004, passing ownership of the Oliver Bridge to the CN. The rail line served by this bridge acts as a southwest bypass for trains around the Twin Ports area. A dozen different railroads have trackage rights over the bridge, resulting in very heavy traffic. The bridge currently hosts an average of 50 trains per day. Many of these trains are multi-engine unit trains hauling coal in from the Power River Basin in Wyoming.
