Winter Seasonal Weights

The purpose of the Winter Seasonal Weights (WSW) program is to allow higher than normal weights on Manitoba highways and roads during the winter season when the roadbed is frozen. The WSW program includes:

  • Winter Weight Premium (WWP)
  • Winter Seasonal RTAC Routes Designation
  • Winter Seasonal Class A1 Highways Designation

The Winter Weight Premium (WWP) allows for an increase of up to 10% in the maximum gross axle weights. For non-RTAC Vehicles this allowance is based on:

  • a single axle or axle group on a class A1 highway or
  • a single axle or axle group on a class B1 highway

as set out in Schedule E of MB Reg 155/2018 Vehicle Weights and Dimensions on Classes of Highways (PDF). The gross vehicle weight cannot exceed the maximum weight allowed for a normal class A1 highway or class B1 highway.

For RTAC vehicles, this allowance is based on:

  • a single axle on an RTAC route
  • tandem axles on a RTAC route up to 17,600 kg maximum
  • a single or tandem axle group on an A1 or B1 highway

as set out in Schedule H of MB Reg 155/2018 Vehicle Weights and Dimensions on Classes of Highways (PDF). The gross vehicle weight cannot exceed the maximum weight allowed for a normal RTAC route, A1 or B1 highway

Winter Seasonal RTAC Routes Designation

Specific portions of class A1 highways and class B1 highways are reclassified as RTAC routes to allow normal RTAC route gross axle weights on all axle units plus the allowable winter weight premium. The gross vehicle weight cannot exceed the maximum weight allowed for a normal RTAC route.
A list of winter seasonal RTAC routes is available in Schedule B subsection 2(1) of MB Reg 155/2018 Vehicle Weights and Dimensions on Classes of Highways (PDF).

Winter Seasonal Class A1 Highways Designation

Specific portions of class B1 highways can be reclassified as class A1 highways to allow normal class A1 highway gross axle weights on all axle units plus the allowable winter weight premium. The gross vehicle weight cannot exceed the maximum weight allowed for a normal class A1 highway
A list of winter seasonal class A1 highways is available in Schedule C subsection 2(1) of MB Reg 155/2018 Vehicle Weights and Dimensions on Classes of Highways (PDF).


Climate Zones

The province has been divided into three different climate zones.

  • Zone 1 is south of the virtual line that includes PTH77, going easterly to include PR 513 (Gypsumville) and the northern tip of Black Island, following the eastern shore of Lake Winnipeg to the north shore of the Winnipeg River, easterly along the north shore of the Winnipeg River to PR 304 and easterly to the Ontario border.
  • Zone 2 is north of the virtual line described above and south of the virtual line that includes Sherridon Road (Sherridon), going easterly to include PR 393, Wabowden Access Road (Wabowden) and Sipiwesk Lake Access Road, and easterly to the Ontario border.
  • Zone 3 is north of the virtual line described above Zone 2

The latest start date for WSW would be:

  • December 21 in Zone 1
  • December 12 in Zone 2
  • December 1 in Zone 3

WSW may be started earlier in any climate zone depending upon weather condition in that climate zone. The earliest end date would be:

  • February 20 in Zone 1 and 2
  • February 25 in Zone 3

The WSW period may be extended in any climate zone based on weather conditions (trend of the thawing index and daily air temperature) in that climate zone.