Spring thaw will end in Zone 2 at 12:01 AM on
Thursday, May 23, 2013. Spring thaw ended in Zones 3, 4, and 5 on May 9, 2013. Spring thaw is still in effect in Zone
Roadway weight restrictions go into effect during the springtime freezing and thawing period, typically from early March until the second week in May. (The 36 year average beginning date for this period is March 10 and the average ending date is May 10.) During this time when some pavements and base materials are at their weakest due to the freezing and thawing cycle occurring,
most* divisible load multiple trip permits exceeding legal axle weights or 80,000 pounds are suspended.
(*Divisible load permits authorized by Wis. Statutes
348.27(9m)(a)4. and 348.27(9t) may operate during spring thaw
subject to terms of each permit.) During the thaw period non-divisible multiple trip
and single trip permits must stay off highway sections designated as
There are approximately 1,400 miles (94 segments) of bituminous highways on the Class II list during the springtime freezing and thawing period. Class II highways currently account for only
12 percent of the state highways.
Class II roadway
(Updated March 25, 2013)
Class II roads include only state highways that are judged to have unstable condition of the roadway subgrade during the period when frost is leaving the ground such that the travel of vehicles with overweight permits would cause undue damage to the roadway.
Local roads are affected by similar conditions and are posted or
restricted as determined by the local maintaining authority.
In accordance with Wisconsin Statutes sections 348.26 and 348.27, the
department may restrict travel of vehicles with overweight permits on certain (Class II) roads due to the unstable condition of the roadway subgrade during the period when frost is leaving the ground.
Typically, restrictions on travel include:
Restrictions on maximum weight allowed for single-trip movement over Class II roads.
Travel under annual non-divisible permits becomes more difficult because holders of overweight annual permits must avoid the Class II roads.
Travel with single-trip or annual non-divisible overweight permits is not restricted on local or state roads in Milwaukee County or any part of the Interstate Highway System. In the remainder of the state, travel is not restricted under non-divisible annual permits on Class I roadways.
Also during this period, other travel restrictions apply:
Suspension of most divisible load permit types on all state highways for the duration of the thaw period.
Exceptions are RS and PS permits.
Important things to know with respect to permits involving 98,000
pounds on 6-axles:
The Wisconsin Department of Transportation (WisDOT) is the
only agency that may issue a “Raw Forest Products Permit” (RS
Permit) per Wis Statute 348.27(9m)(a)4.
The RS Permit authorizes transport of “raw forest products” at
gvw of 98,000 lbs on vehicles or vehicle combinations with six or
more axles none of which may exceed the axle weights set in the
RS Permits are not valid on Interstate highways.
RS permits do not authorize exceeding posted weight limits,
except for seasonal limits on marked State or US routes in
connection with thawing of frozen roads.
During the spring thaw period established by WisDOT, the RS
Permit allows transport on any highway that is marked State or US
route including those posted to limit weights seasonally in
connection with thawing of frozen roads. RS permits also remain
valid during spring thaw on all other public roads but are subject
to all posted weight limits, including seasonal limits.