Lafayette Bluff Tunnel (Bridge 38003)
See features of the bridge
History & significance
The Lafayette Bluff Tunnel (Bridge 38003) was built in 1991 and is a hard-rock tunnel carrying Trunk Highway 61 under the Lafayette Bluff in Silver Creek Township, Lake County. The 852-foot-long and 61-foot-wide structure is significant as the first hard-rock mined tunnel in Minnesota and the Midwest and is notable for the use of the New Austrian Tunneling Method (NATM) used during construction. In addition, because of the excavated width required to accommodate a 60 mile-per-hour design speed and provide adequate sight distance with the sharp four-degree curve, it is one of the widest hard-rock mined tunnels in the nation.
Location
Silver Creek Township (Lake County)
Latitude, Longitude: 47.095566, -91.552185
Bridge features
Notably wide hard-rock mined tunnel using NATM.