 The Department of State Highways expanded US 2 / US 41 into an expressway between Gladstone and Rapid River in 1971 . The state built a new bridge over the Manistique River in 1983 , bypassing downtown . MDOT disposed of the former routing of US 2 into downtown in two ways . The western half was initially an unnumbered state highway until it was later transferred to local control . An extension of M ‑ 94 replaced the remainder , including the Siphon Bridge , through downtown . In that same year , the department truncated US 2 to end in St. Ignace by removing it from the I ‑ 75 freeway . The last changes were made to US 2 's routing through Iron River in 1998 , bypassing the bridge that formerly carried the highway over the river in town . In 2011 , MDOT raised the speed limit along the expressway section in Delta County from 55 to 65 mph ( 89 to 105 km / h ) , although the speed limit for trucks remains 55 mph ( 89 km / h ) . 
