US-10 – M-115 to I-75 (Clare, Isabella, Midland, and Bay counties) I-69 – From the Genesee/Lapeer county line to I-94 (Genesee, Lapeer, and St. I-69 – I-69 Business Route (Saginaw Highway) to Swartz Creek (Clinton, Shiawassee, and Genesee counties) The other corridors reviewed and selected for increased speed limits are: New speed limits will be posted on all of the selected freeway and non-freeway routes prior to mid-November. MDOT and MSP are finalizing the administrative processes and signing traffic control orders to implement increased speed limits on the remaining freeway and non-freeway corridors. "Troopers and motor carrier officers do, and will continue to, aggressively enforce all posted speed limits to ensure compliance by the motoring public." "The engineering and safety studies conducted utilized the 85th-percentile speed, which is a national scientifically proven method to determine and establish safe speed limits," stated Col. "We reviewed design speeds, crash patterns, number of access points, traffic volumes and continuity of these corridors, and chose them to minimize necessary improvements for higher speed limits."
"The corridors identified by MDOT and MSP were selected not only because studies indicated most drivers were already driving at those increased speeds, but also because their design and safety features were best suited to these speed limits," said State Transportation Director Kirk T.
The law requires that these modified speed limits be in place prior to Jan. Public Act 445, passed by the state Legislature in late 2016, tasked the two agencies with increasing speed limits on some state highways and freeways based on 85th-percentile speeds (the speed at or below which 85 percent of traffic is moving) and the results of engineering and safety studies. Select freeway routes will have increased speed limits posted beginning May 1. In accordance with new state law, the Michigan Department of Transportation (MDOT) and Michigan State Police (MSP) have identified 900 miles of non-freeway state highways for speed limit increases to 65 mph, and 600 miles of freeway for speed limit increases to 75 mph.