LANSING – Spring weight restrictions go into effect today across Southern Lower Michigan.

The Michigan Department of Transportation and local agencies are enacting their annual spring weight restrictions to help protect roads. Starting today, weight restrictions will be imposed and enforced on all state trunkline highways from the Michigan-Indiana State Line north to and including M-20 from the interchange with US-31 in Oceans County; then east on M-20 to US-131, then north on US-131 to M-20 in Mecosta County., then east on M-20 to US-10 in Midland County; then east on US-10 to M-25 in Bay City, including the entire Thumb region.

All state trunklines in this area will have weight restrictions imposed and enforced. State routes typically carry M, I or US designations. When roads have been frozen all winter begin to thaw from the surface downward, melting snow and ice saturate the softened ground. During the spring thaw, the road bed softened by trapped moisture beneath the pavement makes it more susceptible to damage. This also contributes to pothole problems already occurring due to the numerous freeze-thaw cycles.

On routes designated as “all season” there will be no reduction in legal axle weights. On routes designated as “seasonal”, there will be a posted weight reduction of 25 percent for frigid or concrete pavements, and a 35 percent reduction for flexible or asphalt pavements. Weight restrictions remain in effect until the frost line is deep enough to allow moisture to escape and the roadbeds regain stability. County Road Commissions and City Public Works Department put in place their own seasonal weight restrictions which usually, but not always, coincide with State highway weight restrictions.