The Michigan Department of Transportation (MDOT) will adjust spring weight restriction areas starting Monday, March 9, as part of its annual efforts to protect roadways during the thawing season.
Beginning at 6 a.m. on that date, weight restrictions will be lifted on all state trunkline highways from the southern border of Michigan northward, following a route that includes M-43 in South Haven, US-131 and I-94 in Kalamazoo County, US-23 in Washtenaw County, I-96 and M-59 in Livingston County, and ending at the I-94 interchange in Macomb County.
North of this route—including the entire Upper Peninsula and Mackinac Island—weight restrictions will remain enforced on all state trunkline highways. These routes are typically identified by M, I, or US designations.
In restricted areas:
– “On routes designated as ‘all-season’ (designated in green and gold on the MDOT Truck Operators Map), there will be no reduction in legal axle weights.”
– “All extended permits will be valid for oversize loads in the weight-restricted area on the restricted routes. Single-trip permits will not be issued for any overweight loads or loads exceeding 14 feet in width, 11 axles, and 150 feet in overall length on the restricted routes.”
– “On routes designated as ‘seasonal’ (designated in solid or dashed red on the MDOT Truck Operators Map), there will be a posted weight reduction of 25 percent for rigid (concrete) pavements and 35 percent for flexible (asphalt) pavements, and maximum speed of 35 mph for some vehicles.”
Drivers are required by law to follow posted speed limits for roads with weight restrictions. Additional information about truck speed restrictions and rules regarding propane fuel delivery or public utility vehicles is available online.
As roads thaw from winter freezing conditions, moisture trapped beneath pavement can soften roadbeds. This increases susceptibility to damage during spring thaw periods—a situation worsened by frequent freeze-thaw cycles throughout winter.
MDOT determines when to implement spring weight restrictions based on frost depth measurements along state highways, monitoring road conditions, and reviewing weather forecasts. Restrictions remain until frost lines recede enough to allow moisture release and restore stability to roadbeds.
Local county road commissions and city public works departments set their own seasonal weight limits which may differ from those imposed by MDOT. Signs usually indicate which routes have active restrictions.
For updates or more information about current weight restrictions—including maps showing all-season versus seasonal roads—call 800-787-8960 or visit www.Michigan.gov/Truckers under “Restrictions.” Email alerts are also available through MDOT’s website. Trucking companies based outside Michigan can call 517-373-6256 for further details.
MDOT manages nearly 10,000 miles of state highways across Michigan along with over 4,800 bridges and other transportation infrastructure such as non-motorized trails and railroad tracks (official website). The department employs more than 2,800 people statewide across seven regions (official website).
The agency oversees maintenance of M-, I-, and US-designated highway systems while also managing bridge upkeep, rail services, transit programs including aviation initiatives—and sets safety standards (official website). Leadership includes a director supported by key executives like chief administrative officer and chief operations officer (official website).
MDOT’s mission is focused on serving people throughout Michigan communities while supporting economic connections via its transportation network (official website).
