That Time of Year Again: Lighten the Load Spring-Like Weather Brings on Weight Restrictions for Roads

Contact: Lt. David Ford (517) 336-6449
Agency: State Police

MARCH 4, 2004



East Lansing.  Along with singing birds and blooming flowers, every spring in Michigan brings heaving and buckling pavement.  Many local jurisdictions in Southern and Mid-Michigan have already implemented "frost law" or reduced loading provisions to protect their roads.  These restrictions drop the legal axle weights of vehicles by either 25% or 35% depending upon the road construction and design.  While Michigan's weight laws apply to all vehicles, reduced loading has the biggest impact on commercial operations, due to the size and weight of the vehicles that are used.


State law provides the months of March, April and May are automatically reduced loading months, but the statute also allows the Michigan Department of Transportation (MDOT) and the county road commission to implement those restrictions earlier or suspend reduced loading, depending upon weather conditions.


Along with reduced loading provisions are reduced speeds.  For vehicles over 10,000 lbs. operated on reduced loading roads, the speed limit drops to a maximum of 35 mph, regardless of the posted limit.  Speed, in conjunction with axle weights, has a tremendous impact on the creation of potholes.


The term "frost law" refers to the amount of frost remaining in the ground.  The warming and cooling of the ground during the up and down weather of spring causes the pavement to heave and buckle, creating potholes and broken pavement.


MDOT has a 24-hour phone number where callers can listen to a recorded message on the current status of reduced loading provisions on state roads by calling 800-787-8960, or by going on-line at  For local roads, contact your county road commission, or go on-line at


Read more press releases from the Michigan State Police.